Too many types in declaration!

fgcp230 2004-09-03 08:54:25
程序代码如下:
#include <stdio.h>
#include <string.h>

struct node
{
struct node * prev;
char * name;
char * qq;
char * mobilephone;
char * email;
struct node* next;
}
struct node * newnode()//tc在此行提示“Too many types in declaration!”,什么原因啊?急!
{
struct node * p;
printf("\nenter your name:");
gets(p->name);
printf("\nenter your qq:");
gets(p->qq);
printf("\nenter your mobilephone:");
gets(p->mobilephone);
printf("\nenter your email:");
gets(p->email);

return (p);
}
void printnode(struct node * p)
{
printf("\nthe name you entered is:%s",p->name);
printf("\nthe qq you entered is:%s",p->qq);
printf("\nthe mobilephone you entered is:%s",p->mobilephone);
printf("\nthe email you entered is:%s",p->email);
return;
}
main()
{
struct node * n1;
clrscr();
n1=newnode();
printnode(n1);
exit(1);

}
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fgcp230 2004-09-03
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确实是掉了分号的问题,感谢sekelon(罗伦罗亚索龙)!!!
Lonelywolf1899 2004-09-03
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sekelon(罗伦罗亚索龙)
---------------------
说得对
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sekelon(罗伦罗亚索龙) 正解
banjo 2004-09-03
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没有预先声明吧

#include <stdio.h>
#include <string.h>

strcut node;//这一句
sekelon 2004-09-03
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struct node
{
struct node * prev;
char * name;
char * qq;
char * mobilephone;
char * email;
struct node* next;
};//<----这个地方少个分号
NativeXml-master This file contains a list of all bugfixes, additions and enhancements to NativeXml. Maintained by Nils Haeck (SimDesign BV) ! = bugfix * = enhancement + = addition Version 4.07 (03oct2012) ! Improved canonicalization (c14n), now works recursively and returns # expanded entities ! Fixed up a rangecheck warning in sdUtf8ToWideBuffer ! cleaned up some compiler directives Version 4.06 (16aug2012) + Added TXmlNode.NodeRemoveEx (allows removal of the line with the node instead of just the node itself) - experimental Version 4.05 (11aug2012) ! Reimplemented/Fixed sdNormaliseEol function + Readded (hex) character replacement Version 4.04 (06aug2012) ! Updated simdesign.inc to add DXE2 ! Fixed bug in DirectNodeCount ! Fixed (removed) erratic un-normalisation ! removed erratic $ifdef in NativeXmlObjectStorage.pas Version 4.03 (13jul2012) * Core End-Of-Line style is LF, defaults CR-LF, LF and CR for Windows, Linux, Mac respectively ! Fixed EOL bug in source (thx Christian) * TsdChardata.GetCoreValue and .GetPlatformValue Version 4.02 (05nov2011) * default end-of-line style now esCRLF (uses CR-LF combination by default for Windows) + form storage in editor (both default and XE versions) uses NativeXml itself :) + added support for EolStyle = esCR (for use with the Mac) + added separator when writing declaration, skip separator when parsing declaration ! fixed problems in binary xml. Consequence: New binary xml version v2. * NativeXml (and binary xml) now supports xml-stylesheet correctly * binary xml now supports doctype correctly * fixed attribute processing in NativeXmlStorage.pas (thanks RKS) Version 4.01 (27jul2011) + added binary xml to the TNativeXml class itself + added methods BinaryMethod and AesKeyHex * improved FixStructuralErrors.. NativeXml can now load html usually * improved method sdUnNormalizeEol (faster now) ! fixed property handlers for ExternalEncoding and ExternalCodepage + updated DtpEditor XE Version 4.00 (23jul2011) + implemented binary xml (BXM) + added ValueAsDate and ValueAsTime besides ValueAsDateTime + added SplitSecondDigits parameter (default = 0) * constructor CreateParentNear instead of CreateParentBefore/After to avoid clash with CppBuilder + added zlib compression and AES encryption for BXM in the demo Version 3.32 (07jul2011) ! re-added D5 compatibility ! fixed TNativeXml.New method Version 3.31 (29jun2011) ! fixed string table (part of lowlevel string processing of NativeXml) * integrated End-Of-Line normalisation in the XML parser * placed NativeXmlC14N.pas in NativeXml.pas, TNativeXml.Canonicalize integrated Version 3.30 (20may2011) * reimplemented DropCommentsOnParse * reimplemented AttributesClear + added property Charset ! reworked write FExternalEncoding * readded EncodeBinHex / DecodeBinHex + sdNodeList with default Create * alphabetized NativeXml bool options + Linux: allow many codepage conversions, using NativeXmlWin32Compat.pas (largely untested tho) * added class methods TNativeXml.EncodeBase64 / DecodeBase64 next to the global base64 coding methods. ! corrected ranges of arrays in the coders, so rangechecking does not need to be disabled * slightly more verbose error messages (line + pos instead of just pos) Version 3.29 (01apr2011) ! fixed last part of the file processing (final chunk) so NormalizeEOL works correctly now ! fix: changed boolean value strings 'True' and 'False' to 'true' and 'false' according to W3 spec + Added some helper functions for Linux (still experimental), this does not affect Win32 * Joined TsdBufferParser and TsdXmlParser (now just TsdXmlParser) * Updated OnProgress and added progress bar in XmlEditor Version 3.28 (21mar2011) + Re-added NodeNewAtIndex * Verified and fixed demos Version 3.27 (19mar2011) ! fixed Delphi XE-related bug in sdEscapeString + Re-added method NodesClear + Re-added methods ValueUnicode, AttributeValueByNameWide, IndexInParent, SortChildNodes + made AttributeIndexByName public + Re-added constructors TXmlNode.CreateName, CreateNameValue Version 3.26 (16mar2011) * TCustomXml and TNativeXml joined + Added property TXmlNode.Document (type TNativeXml) + Added ReadUnicodeString / WriteUnicodeString * Made NodeFindOrCreate public ! Fixed FWriteOnDefault + Added ReadAttributeBool, ReadAttributeString, ReadUnicodeString and WriteUnicodeString Version 3.25 (03mar2011) * enhanced function sdEscapeString (contributor: Michael Cessna) ! Fixed function sdReplaceString (new implementation) + Added Test16 to verify sdEscapeString and sdReplaceString Version 3.24 (24feb2011) + Added function TCustomXml.InsertDocType to hide the complexity of inserting a TsdDocType manually ! fixed small leak in class TsdDocType + Added Test15 to diagnose TCustomXml.InsertDocType ! fixed major bug where parser does not use ansi + 65001 codepage but really utf8, so the writer also uses utf8 (and added Test14 to check) * Added speed comparison between old TNativeXml and new TNativeXml: new TNativeXml is ca 3 times faster than old. + TNativeXmlObjectStorage: Added storage of TCollectionItem and removed some "with" statements and replaced some raise statements by DoDebugOut * Tested successfully with D5, D7 and DXE Version 3.23 (13feb2011) * Reimplemented TXmlNode.IsEqualTo + Added Test12 (to check IsEqualTo) + Added D5 compatibility (through sdDebug.pas) + Option "FixStructuralErrors" is functional: With this option you can fix the structure in HTML files (eg a <meta> tag without closing tag). Version 3.22 (08feb2011) ! fixed accidental switch of TCustomXml(FOwner).DoNodeLoaded/DoNodeNew; ! fixed attribute handling of values (added sdReplaceString) + Added UTF16BE support in SaveToStream ! Renamed WriteToString/WideString to WriteToLocalString/Widestring for Utf8 and Utf16, and added generic WriteToString for "string" type + Added readonly property TXmlNode.DirectNodeCount + Added properties TXmlNode.ChildContainers[i] and TXmlNode.ChildContainerCount + Added Test5, Test6 and Test7 functions in XmlTest demo app * placed sdStringEncoding and sdBufferParser in NativeXml (no longer needs separate units) + Minor improvements in writing xml elements with XmlFormat := xfReadable Version 3.21 (04feb2011) ! Re-added sdStringToDateTime functions instead of non-functional StrToDateTime ! Fixed function sdNormaliseEOL + Re-added TXmlNode.Delete + Added Test3 and Test4 functions in XmlTest demo app Version 3.20 (31jan2011) * Combined NativeXmlEx, NativeXmlNodes, NativeXmlParser and NativeXmlUtils into one new unit NativeXml - Removed old NativeXml + Added WriteToString method for the TXmlNode classes + Added Assign and CopyFrom methods for the TXmlNode classes + Added a few methods from the old NativeXml (e.g. DeleteEmptyNodes) * sdStreams no longer needs sdStreamsPlatform * Generalized include files Version 3.14 (24jan2011) + Added LINQ-like methods and example (contributor: Marius Z) + Reimplemented ValueAsXYZ methods in NativeXmlEx * Added and enhanced XmlFormat = xfPreserve + Verified successful working in both D7 and DXE Version 3.13 (16jan2011) + NativeXmlObjectStorage now works with NativeXmlEx * Many improvements in the writer (NativeXmlNodes) ! Fixed Utf8 to Ansi (sdStringEncoding) * Dual version of XmlEditorEx demo for D7 and DXE by use of {$ifdef}'s Version 3.12 (31dec2010) + Experimental unit NativeXmlC14n.pas (for canonicalization) ! Many bugfixes in NativeXmlEx parser + normalize end-of-line * NativeXmlEx html online docu * XmlEditorEx demo with versions for Delphi7 and DelphiXE Version 3.11 (28nov2010) + Implemented NativeXmlEx: NativeXmlEx.pas (TCustomXmlEx and TNativeXmlEx components) NativeXmlNodes.pas (TXmlNode and descendant nodes like TsdAttribute and TsdElement) NativeXmlUtils.pas (lowlevel types and consts of nativexml, codepage constants, low-level string handling functions) NativeXmlParser.pas (TsdXmlParser and TsdXmlWriter components) sdStringTable.pas in /general sdStringEncoding.pas in /general sdStreams.pas in /general sdStreamsPlatform.pas in /general sdBufferParser.pas in /general sdDebug.pas in /general sdSortedLists.pas in /general ! fixed WriteAttributeInt64 and WriteInt64 (NativeXml.pas) Version 3.10 (21sep2010) ! fixed local bias in datetime processing (contributor Stefan Glienke) ! XML without encoding should be UTF-8 ! default values In ReadAttributeXXX when empty strings instead of exceptions ! Allow multiple defined properties ! fixed bug in varCurrency values when reading variants ! No info stored in stream in procedure ObjectSaveToXmlXXXX ! Problem with saving/reading collections (contributor Adam Siwon) Version 3.09 (21jul2010) ! allow "utf-8" as well as "UTF-8" as encodingstring (NativeXml.pas) ! trim string values in normal elements (NativeXml.pas hack) ! RawByteString instead of UTF8String in TsdXmlObjectWriter (NativeXmlObjectStorage) + exception 'Unregistered classtype encountered in nodename' instead of general exception (NativeXmlObjectStorage) ! Local bias (daylightsaving) and time zone designator in date/time conversion (contributor Stefan Glienke) Version 3.08 (25jun2010) ! do not write BOM when encoding="UTF-8" Version 3.07 (10Mar2010) ! fixed TXmlNode.SetValueAsInt64 Version 3.06 (03Feb2010) * Added compiler directives for NativeXmlStorage.pas ! Fixed "implicit string conversion" warnings in examples Version 3.05 (19Dec2009) * Added some compiler directives for D2009/D2010 Version 3.04 (28Nov2009) * Changed license of NativeXml to very liberal and comprehensible BSD-Style Open-Source Version 3.03 ! Added {$ELSE} directive and declarations for UnicodeChar and PUnicodeChar Version 3.02 ! Bugfix in attribute value code Version 3.00 (20Sep2009) * Made compatible with D2009 and its convention that string is unicode (2bytes/char) Version 2.39 * Replaced all widestring by WideString (conform to case used in Delphi) Version 2.38 (07March2008) + Added TXmlNode.ReadAttributeDateTime + Added TXmlNode.WriteAttributeDateTime + Support for D2007-NET (version 190) ! ReadFromStream now first clears subnodes Version 2.37 (18Dec2007) + Added ByAttribute function to TXmlNodeList ! Fixed problem with NodeAdd from another tree (Document reference gets updated now) ! Fixed deletion of empty attributes Version 2.36 (11Nov2007) ! Do not save empty encoding (e.g. encoding=""). * Renamed some local variables * Code re-formatted Version 2.35 (17Aug2007) * Bugfix in sdWriteNumber Version 2.34 (31May2007) + Added WriteAttributeInt64 ! Made check for UTF-8 case insensitive * Fixed bug with stringtable (removed "gaps") + Added AttributeValueDirect prop Version 2.31 (03May2007) * Verified compatibility with Delphi2 and 3 * Fixed 2 harmless compiler warnings Version 2.30 (30Apr2007) + Added stringbuilder class for faster creation of strings. This should make NativeXml parse documents with large value strings faster. + Patches to allow compilation under freepascal ! Fixed bug with ' and " inside quotes (now "bla'bla'bla" is allowed) * ReadAttributeBool/WriteAttributeBool allow empty elements * Made changes to assure NativeXml works well with "boolean evaluation" compile flag on ! Fixed bug in WriteWidestrProp ! Fixed bug in SetValueAsFloat ! Fixed bug in SetAttributeByNameWide Version 2.26 (05Dec2006) + Added ReadAttributeInt64 property ! Fixed bugs with StrToInt which should be StrToInt64. ! Fixed bug with tag parsing where tags like "bla>bla" caused the parser to stop on the ">". Version 2.23 (02Dec2005) ! Fixed bug in entity resolving for attributes ! Bugfix: Take into account default value in WriteAttributeString/-Integer ! Bugfix: Never write empty attributes to the XML file + Added TotalNodeCount property * Removed TNativeXml.StyleSheetString, replaced by TNativeXml.StyleSheetNode * WriteFloat now uses proprietary routine (threadsafe), always using a dot as decimal separator and settings from NativeXml.FloatSignificantDigits and FloatAllowScientific Version 2.20 (19Sep2005) + Added SortAttributes property + Added ParserWarnings property * Added RootNodeList property, to allow easier access to XML nodes in the header, and removed ExtraNodes and Comments properties. + Added TXmlNode.IsEqualTo function to compare nodes in documents ! Fixed bug in FullPath property (one slash too much at start) * FindNodes can now also be used with full paths ! Bugfix: no longer adds CRLF after ENTITY declarations ! Bugfix: AttributeName[] setter now no longer strips quotes from attribute value. + Added AttributeValueAsWidestring[] property + Added AttributeValueAsInteger[] property Version 2.13 (25Jul2005) ! Fixed bug with begin-tag reading (only seldom, with <?..?> nodes) Version 2.12 (25Jul2005) * Changed order of DoNodeLoaded and DoProgress, to avoid bug when freeing in OnNodeLoaded. + Added SortAttributes property + Added ParserWarnings property * Added RootNodeList property, to allow easier access to XML nodes in the header - Removed ExtraNodes and Comments properties * Changed Assign methods (faster now) + Added function TXmlNode.NodeByElementType + Added boolean property TNativeXml.AbortParsing ! Fixed bug with end-tag reading (when reading CDATA sections with \"]\" in the data string) Version 1.00 (01Apr2003) - Initial release
Table of Contents Header Files The #define Guard Header File Dependencies Inline Functions The -inl.h Files Function Parameter Ordering Names and Order of Includes Scoping Namespaces Nested Classes Nonmember, Static Member, and Global Functions Local Variables Static and Global Variables Classes Doing Work in Constructors Default Constructors Explicit Constructors Copy Constructors Structs vs. Classes Inheritance Multiple Inheritance Interfaces Operator Overloading Access Control Declaration Order Write Short Functions Google-Specific Magic Smart Pointers cpplint Other C++ Features Reference Arguments Function Overloading Default Arguments Variable-Length Arrays and alloca() Friends Exceptions Run-Time Type Information (RTTI) Casting Streams Preincrement and Predecrement Use of const Integer Types 64-bit Portability Preprocessor Macros 0 and NULL sizeof Boost C++0x Naming General Naming Rules File Names Type Names Variable Names Constant Names Function Names Namespace Names Enumerator Names Macro Names Exceptions to Naming Rules Comments Comment Style File Comments Class Comments Function Comments Variable Comments Implementation Comments Punctuation, Spelling and Grammar TODO Comments Deprecation Comments Formatting Line Length Non-ASCII Characters Spaces vs. Tabs Function Declarations and Definitions Function Calls Conditionals Loops and Switch Statements Pointer and Reference Expressions Boolean Expressions Return Values Variable and Array Initialization Preprocessor Directives Class Format Constructor Initializer Lists Namespace Formatting Horizontal Whitespace Vertical Whitespace Exceptions to the Rules Existing Non-conformant Code Windows Code Important Note Displaying Hidden Details in this Guide link ▶This style guide contains many details that are initially hidden from view. They are marked by the triangle icon, which you see here on your left. Click it now. You should see "Hooray" appear below. Hooray! Now you know you can expand points to get more details. Alternatively, there's an "expand all" at the top of this document. Background C++ is the main development language used by many of Google's open-source projects. As every C++ programmer knows, the language has many powerful features, but this power brings with it complexity, which in turn can make code more bug-prone and harder to read and maintain. The goal of this guide is to manage this complexity by describing in detail the dos and don'ts of writing C++ code. These rules exist to keep the code base manageable while still allowing coders to use C++ language features productively. Style, also known as readability, is what we call the conventions that govern our C++ code. The term Style is a bit of a misnomer, since these conventions cover far more than just source file formatting. One way in which we keep the code base manageable is by enforcing consistency. It is very important that any programmer be able to look at another's code and quickly understand it. Maintaining a uniform style and following conventions means that we can more easily use "pattern-matching" to infer what various symbols are and what invariants are true about them. Creating common, required idioms and patterns makes code much easier to understand. In some cases there might be good arguments for changing certain style rules, but we nonetheless keep things as they are in order to preserve consistency. Another issue this guide addresses is that of C++ feature bloat. C++ is a huge language with many advanced features. In some cases we constrain, or even ban, use of certain features. We do this to keep code simple and to avoid the various common errors and problems that these features can cause. This guide lists these features and explains why their use is restricted. Open-source projects developed by Google conform to the requirements in this guide. Note that this guide is not a C++ tutorial: we assume that the reader is familiar with the language. Header Files In general, every .cc file should have an associated .h file. There are some common exceptions, such as unittests and small .cc files containing just a main() function. Correct use of header files can make a huge difference to the readability, size and performance of your code. The following rules will guide you through the various pitfalls of using header files. The #define Guard link ▶All header files should have #define guards to prevent multiple inclusion. The format of the symbol name should be ___H_. To guarantee uniqueness, they should be based on the full path in a project's source tree. For example, the file foo/src/bar/baz.h in project foo should have the following guard: #ifndef FOO_BAR_BAZ_H_ #define FOO_BAR_BAZ_H_ ... #endif // FOO_BAR_BAZ_H_ Header File Dependencies link ▶Don't use an #include when a forward declaration would suffice. When you include a header file you introduce a dependency that will cause your code to be recompiled whenever the header file changes. If your header file includes other header files, any change to those files will cause any code that includes your header to be recompiled. Therefore, we prefer to minimize includes, particularly includes of header files in other header files. You can significantly minimize the number of header files you need to include in your own header files by using forward declarations. For example, if your header file uses the File class in ways that do not require access to the declaration of the File class, your header file can just forward declare class File; instead of having to #include "file/base/file.h". How can we use a class Foo in a header file without access to its definition? We can declare data members of type Foo* or Foo&. We can declare (but not define) functions with arguments, and/or return values, of type Foo. (One exception is if an argument Foo or const Foo& has a non-explicit, one-argument constructor, in which case we need the full definition to support automatic type conversion.) We can declare static data members of type Foo. This is because static data members are defined outside the class definition. On the other hand, you must include the header file for Foo if your class subclasses Foo or has a data member of type Foo. Sometimes it makes sense to have pointer (or better, scoped_ptr) members instead of object members. However, this complicates code readability and imposes a performance penalty, so avoid doing this transformation if the only purpose is to minimize includes in header files. Of course, .cc files typically do require the definitions of the classes they use, and usually have to include several header files. Note: If you use a symbol Foo in your source file, you should bring in a definition for Foo yourself, either via an #include or via a forward declaration. Do not depend on the symbol being brought in transitively via headers not directly included. One exception is if Foo is used in myfile.cc, it's ok to #include (or forward-declare) Foo in myfile.h, instead of myfile.cc. Inline Functions link ▶Define functions inline only when they are small, say, 10 lines or less. Definition: You can declare functions in a way that allows the compiler to expand them inline rather than calling them through the usual function call mechanism. Pros: Inlining a function can generate more efficient object code, as long as the inlined function is small. Feel free to inline accessors and mutators, and other short, performance-critical functions. Cons: Overuse of inlining can actually make programs slower. Depending on a function's size, inlining it can cause the code size to increase or decrease. Inlining a very small accessor function will usually decrease code size while inlining a very large function can dramatically increase code size. On modern processors smaller code usually runs faster due to better use of the instruction cache. Decision: A decent rule of thumb is to not inline a function if it is more than 10 lines long. Beware of destructors, which are often longer than they appear because of implicit member- and base-destructor calls! Another useful rule of thumb: it's typically not cost effective to inline functions with loops or switch statements (unless, in the common case, the loop or switch statement is never executed). It is important to know that functions are not always inlined even if they are declared as such; for example, virtual and recursive functions are not normally inlined. Usually recursive functions should not be inline. The main reason for making a virtual function inline is to place its definition in the class, either for convenience or to document its behavior, e.g., for accessors and mutators. The -inl.h Files link ▶You may use file names with a -inl.h suffix to define complex inline functions when needed. The definition of an inline function needs to be in a header file, so that the compiler has the definition available for inlining at the call sites. However, implementation code properly belongs in .cc files, and we do not like to have much actual code in .h files unless there is a readability or performance advantage. If an inline function definition is short, with very little, if any, logic in it, you should put the code in your .h file. For example, accessors and mutators should certainly be inside a class definition. More complex inline functions may also be put in a .h file for the convenience of the implementer and callers, though if this makes the .h file too unwieldy you can instead put that code in a separate -inl.h file. This separates the implementation from the class definition, while still allowing the implementation to be included where necessary. Another use of -inl.h files is for definitions of function templates. This can be used to keep your template definitions easy to read. Do not forget that a -inl.h file requires a #define guard just like any other header file. Function Parameter Ordering link ▶When defining a function, parameter order is: inputs, then outputs. Parameters to C/C++ functions are either input to the function, output from the function, or both. Input parameters are usually values or const references, while output and input/output parameters will be non-const pointers. When ordering function parameters, put all input-only parameters before any output parameters. In particular, do not add new parameters to the end of the function just because they are new; place new input-only parameters before the output parameters. This is not a hard-and-fast rule. Parameters that are both input and output (often classes/structs) muddy the waters, and, as always, consistency with related functions may require you to bend the rule. Names and Order of Includes link ▶Use standard order for readability and to avoid hidden dependencies: C library, C++ library, other libraries' .h, your project's .h. All of a project's header files should be listed as descentants of the project's source directory without use of UNIX directory shortcuts . (the current directory) or .. (the parent directory). For example, google-awesome-project/src/base/logging.h should be included as #include "base/logging.h" In dir/foo.cc, whose main purpose is to implement or test the stuff in dir2/foo2.h, order your includes as follows: dir2/foo2.h (preferred location — see details below). C system files. C++ system files. Other libraries' .h files. Your project's .h files. The preferred ordering reduces hidden dependencies. We want every header file to be compilable on its own. The easiest way to achieve this is to make sure that every one of them is the first .h file #included in some .cc. dir/foo.cc and dir2/foo2.h are often in the same directory (e.g. base/basictypes_test.cc and base/basictypes.h), but can be in different directories too. Within each section it is nice to order the includes alphabetically. For example, the includes in google-awesome-project/src/foo/internal/fooserver.cc might look like this: #include "foo/public/fooserver.h" // Preferred location. #include #include #include #include #include "base/basictypes.h" #include "base/commandlineflags.h" #include "foo/public/bar.h" Scoping Namespaces link ▶Unnamed namespaces in .cc files are encouraged. With named namespaces, choose the name based on the project, and possibly its path. Do not use a using-directive. Definition: Namespaces subdivide the global scope into distinct, named scopes, and so are useful for preventing name collisions in the global scope. Pros: Namespaces provide a (hierarchical) axis of naming, in addition to the (also hierarchical) name axis provided by classes. For example, if two different projects have a class Foo in the global scope, these symbols may collide at compile time or at runtime. If each project places their code in a namespace, project1::Foo and project2::Foo are now distinct symbols that do not collide. Cons: Namespaces can be confusing, because they provide an additional (hierarchical) axis of naming, in addition to the (also hierarchical) name axis provided by classes. Use of unnamed spaces in header files can easily cause violations of the C++ One Definition Rule (ODR). Decision: Use namespaces according to the policy described below. Unnamed Namespaces Unnamed namespaces are allowed and even encouraged in .cc files, to avoid runtime naming conflicts: namespace { // This is in a .cc file. // The content of a namespace is not indented enum { kUnused, kEOF, kError }; // Commonly used tokens. bool AtEof() { return pos_ == kEOF; } // Uses our namespace's EOF. } // namespace However, file-scope declarations that are associated with a particular class may be declared in that class as types, static data members or static member functions rather than as members of an unnamed namespace. Terminate the unnamed namespace as shown, with a comment // namespace. Do not use unnamed namespaces in .h files. Named Namespaces Named namespaces should be used as follows: Namespaces wrap the entire source file after includes, gflags definitions/declarations, and forward declarations of classes from other namespaces: // In the .h file namespace mynamespace { // All declarations are within the namespace scope. // Notice the lack of indentation. class MyClass { public: ... void Foo(); }; } // namespace mynamespace // In the .cc file namespace mynamespace { // Definition of functions is within scope of the namespace. void MyClass::Foo() { ... } } // namespace mynamespace The typical .cc file might have more complex detail, including the need to reference classes in other namespaces. #include "a.h" DEFINE_bool(someflag, false, "dummy flag"); class C; // Forward declaration of class C in the global namespace. namespace a { class A; } // Forward declaration of a::A. namespace b { ...code for b... // Code goes against the left margin. } // namespace b Do not declare anything in namespace std, not even forward declarations of standard library classes. Declaring entities in namespace std is undefined behavior, i.e., not portable. To declare entities from the standard library, include the appropriate header file. You may not use a using-directive to make all names from a namespace available. // Forbidden -- This pollutes the namespace. using namespace foo; You may use a using-declaration anywhere in a .cc file, and in functions, methods or classes in .h files. // OK in .cc files. // Must be in a function, method or class in .h files. using ::foo::bar; Namespace aliases are allowed anywhere in a .cc file, anywhere inside the named namespace that wraps an entire .h file, and in functions and methods. // Shorten access to some commonly used names in .cc files. namespace fbz = ::foo::bar::baz; // Shorten access to some commonly used names (in a .h file). namespace librarian { // The following alias is available to all files including // this header (in namespace librarian): // alias names should therefore be chosen consistently // within a project. namespace pd_s = ::pipeline_diagnostics::sidetable; inline void my_inline_function() { // namespace alias local to a function (or method). namespace fbz = ::foo::bar::baz; ... } } // namespace librarian Note that an alias in a .h file is visible to everyone #including that file, so public headers (those available outside a project) and headers transitively #included by them, should avoid defining aliases, as part of the general goal of keeping public APIs as small as possible. Nested Classes link ▶Although you may use public nested classes when they are part of an interface, consider a namespace to keep declarations out of the global scope. Definition: A class can define another class within it; this is also called a member class. class Foo { private: // Bar is a member class, nested within Foo. class Bar { ... }; }; Pros: This is useful when the nested (or member) class is only used by the enclosing class; making it a member puts it in the enclosing class scope rather than polluting the outer scope with the class name. Nested classes can be forward declared within the enclosing class and then defined in the .cc file to avoid including the nested class definition in the enclosing class declaration, since the nested class definition is usually only relevant to the implementation. Cons: Nested classes can be forward-declared only within the definition of the enclosing class. Thus, any header file manipulating a Foo::Bar* pointer will have to include the full class declaration for Foo. Decision: Do not make nested classes public unless they are actually part of the interface, e.g., a class that holds a set of options for some method. Nonmember, Static Member, and Global Functions link ▶Prefer nonmember functions within a namespace or static member functions to global functions; use completely global functions rarely. Pros: Nonmember and static member functions can be useful in some situations. Putting nonmember functions in a namespace avoids polluting the global namespace. Cons: Nonmember and static member functions may make more sense as members of a new class, especially if they access external resources or have significant dependencies. Decision: Sometimes it is useful, or even necessary, to define a function not bound to a class instance. Such a function can be either a static member or a nonmember function. Nonmember functions should not depend on external variables, and should nearly always exist in a namespace. Rather than creating classes only to group static member functions which do not share static data, use namespaces instead. Functions defined in the same compilation unit as production classes may introduce unnecessary coupling and link-time dependencies when directly called from other compilation units; static member functions are particularly susceptible to this. Consider extracting a new class, or placing the functions in a namespace possibly in a separate library. If you must define a nonmember function and it is only needed in its .cc file, use an unnamed namespace or static linkage (eg static int Foo() {...}) to limit its scope. Local Variables link ▶Place a function's variables in the narrowest scope possible, and initialize variables in the declaration. C++ allows you to declare variables anywhere in a function. We encourage you to declare them in as local a scope as possible, and as close to the first use as possible. This makes it easier for the reader to find the declaration and see what type the variable is and what it was initialized to. In particular, initialization should be used instead of declaration and assignment, e.g. int i; i = f(); // Bad -- initialization separate from declaration. int j = g(); // Good -- declaration has initialization. Note that gcc implements for (int i = 0; i < 10; ++i) correctly (the scope of i is only the scope of the for loop), so you can then reuse i in another for loop in the same scope. It also correctly scopes declarations in if and while statements, e.g. while (const char* p = strchr(str, '/')) str = p + 1; There is one caveat: if the variable is an object, its constructor is invoked every time it enters scope and is created, and its destructor is invoked every time it goes out of scope. // Inefficient implementation: for (int i = 0; i < 1000000; ++i) { Foo f; // My ctor and dtor get called 1000000 times each. f.DoSomething(i); } It may be more efficient to declare such a variable used in a loop outside that loop: Foo f; // My ctor and dtor get called once each. for (int i = 0; i < 1000000; ++i) { f.DoSomething(i); } Static and Global Variables link ▶Static or global variables of class type are forbidden: they cause hard-to-find bugs due to indeterminate order of construction and destruction. Objects with static storage duration, including global variables, static variables, static class member variables, and function static variables, must be Plain Old Data (POD): only ints, chars, floats, or pointers, or arrays/structs of POD. The order in which class constructors and initializers for static variables are called is only partially specified in C++ and can even change from build to build, which can cause bugs that are difficult to find. Therefore in addition to banning globals of class type, we do not allow static POD variables to be initialized with the result of a function, unless that function (such as getenv(), or getpid()) does not itself depend on any other globals. Likewise, the order in which destructors are called is defined to be the reverse of the order in which the constructors were called. Since constructor order is indeterminate, so is destructor order. For example, at program-end time a static variable might have been destroyed, but code still running -- perhaps in another thread -- tries to access it and fails. Or the destructor for a static 'string' variable might be run prior to the destructor for another variable that contains a reference to that string. As a result we only allow static variables to contain POD data. This rule completely disallows vector (use C arrays instead), or string (use const char []). If you need a static or global variable of a class type, consider initializing a pointer (which will never be freed), from either your main() function or from pthread_once(). Note that this must be a raw pointer, not a "smart" pointer, since the smart pointer's destructor will have the order-of-destructor issue that we are trying to avoid. Classes Classes are the fundamental unit of code in C++. Naturally, we use them extensively. This section lists the main dos and don'ts you should follow when writing a class. Doing Work in Constructors link ▶In general, constructors should merely set member variables to their initial values. Any complex initialization should go in an explicit Init() method. Definition: It is possible to perform initialization in the body of the constructor. Pros: Convenience in typing. No need to worry about whether the class has been initialized or not. Cons: The problems with doing work in constructors are: There is no easy way for constructors to signal errors, short of using exceptions (which are forbidden). If the work fails, we now have an object whose initialization code failed, so it may be an indeterminate state. If the work calls virtual functions, these calls will not get dispatched to the subclass implementations. Future modification to your class can quietly introduce this problem even if your class is not currently subclassed, causing much confusion. If someone creates a global variable of this type (which is against the rules, but still), the constructor code will be called before main(), possibly breaking some implicit assumptions in the constructor code. For instance, gflags will not yet have been initialized. Decision: If your object requires non-trivial initialization, consider having an explicit Init() method. In particular, constructors should not call virtual functions, attempt to raise errors, access potentially uninitialized global variables, etc. Default Constructors link ▶You must define a default constructor if your class defines member variables and has no other constructors. Otherwise the compiler will do it for you, badly. Definition: The default constructor is called when we new a class object with no arguments. It is always called when calling new[] (for arrays). Pros: Initializing structures by default, to hold "impossible" values, makes debugging much easier. Cons: Extra work for you, the code writer. Decision: If your class defines member variables and has no other constructors you must define a default constructor (one that takes no arguments). It should preferably initialize the object in such a way that its internal state is consistent and valid. The reason for this is that if you have no other constructors and do not define a default constructor, the compiler will generate one for you. This compiler generated constructor may not initialize your object sensibly. If your class inherits from an existing class but you add no new member variables, you are not required to have a default constructor. Explicit Constructors link ▶Use the C++ keyword explicit for constructors with one argument. Definition: Normally, if a constructor takes one argument, it can be used as a conversion. For instance, if you define Foo::Foo(string name) and then pass a string to a function that expects a Foo, the constructor will be called to convert the string into a Foo and will pass the Foo to your function for you. This can be convenient but is also a source of trouble when things get converted and new objects created without you meaning them to. Declaring a constructor explicit prevents it from being invoked implicitly as a conversion. Pros: Avoids undesirable conversions. Cons: None. Decision: We require all single argument constructors to be explicit. Always put explicit in front of one-argument constructors in the class definition: explicit Foo(string name); The exception is copy constructors, which, in the rare cases when we allow them, should probably not be explicit. Classes that are intended to be transparent wrappers around other classes are also exceptions. Such exceptions should be clearly marked with comments. Copy Constructors link ▶Provide a copy constructor and assignment operator only when necessary. Otherwise, disable them with DISALLOW_COPY_AND_ASSIGN. Definition: The copy constructor and assignment operator are used to create copies of objects. The copy constructor is implicitly invoked by the compiler in some situations, e.g. passing objects by value. Pros: Copy constructors make it easy to copy objects. STL containers require that all contents be copyable and assignable. Copy constructors can be more efficient than CopyFrom()-style workarounds because they combine construction with copying, the compiler can elide them in some contexts, and they make it easier to avoid heap allocation. Cons: Implicit copying of objects in C++ is a rich source of bugs and of performance problems. It also reduces readability, as it becomes hard to track which objects are being passed around by value as opposed to by reference, and therefore where changes to an object are reflected. Decision: Few classes need to be copyable. Most should have neither a copy constructor nor an assignment operator. In many situations, a pointer or reference will work just as well as a copied value, with better performance. For example, you can pass function parameters by reference or pointer instead of by value, and you can store pointers rather than objects in an STL container. If your class needs to be copyable, prefer providing a copy method, such as CopyFrom() or Clone(), rather than a copy constructor, because such methods cannot be invoked implicitly. If a copy method is insufficient in your situation (e.g. for performance reasons, or because your class needs to be stored by value in an STL container), provide both a copy constructor and assignment operator. If your class does not need a copy constructor or assignment operator, you must explicitly disable them. To do so, add dummy declarations for the copy constructor and assignment operator in the private: section of your class, but do not provide any corresponding definition (so that any attempt to use them results in a link error). For convenience, a DISALLOW_COPY_AND_ASSIGN macro can be used: // A macro to disallow the copy constructor and operator= functions // This should be used in the private: declarations for a class #define DISALLOW_COPY_AND_ASSIGN(TypeName) \ TypeName(const TypeName&); \ void operator=(const TypeName&) Then, in class Foo: class Foo { public: Foo(int f); ~Foo(); private: DISALLOW_COPY_AND_ASSIGN(Foo); }; Structs vs. Classes link ▶Use a struct only for passive objects that carry data; everything else is a class. The struct and class keywords behave almost identically in C++. We add our own semantic meanings to each keyword, so you should use the appropriate keyword for the data-type you're defining. structs should be used for passive objects that carry data, and may have associated constants, but lack any functionality other than access/setting the data members. The accessing/setting of fields is done by directly accessing the fields rather than through method invocations. Methods should not provide behavior but should only be used to set up the data members, e.g., constructor, destructor, Initialize(), Reset(), Validate(). If more functionality is required, a class is more appropriate. If in doubt, make it a class. For consistency with STL, you can use struct instead of class for functors and traits. Note that member variables in structs and classes have different naming rules. Inheritance link ▶Composition is often more appropriate than inheritance. When using inheritance, make it public. Definition: When a sub-class inherits from a base class, it includes the definitions of all the data and operations that the parent base class defines. In practice, inheritance is used in two major ways in C++: implementation inheritance, in which actual code is inherited by the child, and interface inheritance, in which only method names are inherited. Pros: Implementation inheritance reduces code size by re-using the base class code as it specializes an existing type. Because inheritance is a compile-time declaration, you and the compiler can understand the operation and detect errors. Interface inheritance can be used to programmatically enforce that a class expose a particular API. Again, the compiler can detect errors, in this case, when a class does not define a necessary method of the API. Cons: For implementation inheritance, because the code implementing a sub-class is spread between the base and the sub-class, it can be more difficult to understand an implementation. The sub-class cannot override functions that are not virtual, so the sub-class cannot change implementation. The base class may also define some data members, so that specifies physical layout of the base class. Decision: All inheritance should be public. If you want to do private inheritance, you should be including an instance of the base class as a member instead. Do not overuse implementation inheritance. Composition is often more appropriate. Try to restrict use of inheritance to the "is-a" case: Bar subclasses Foo if it can reasonably be said that Bar "is a kind of" Foo. Make your destructor virtual if necessary. If your class has virtual methods, its destructor should be virtual. Limit the use of protected to those member functions that might need to be accessed from subclasses. Note that data members should be private. When redefining an inherited virtual function, explicitly declare it virtual in the declaration of the derived class. Rationale: If virtual is omitted, the reader has to check all ancestors of the class in question to determine if the function is virtual or not. Multiple Inheritance link ▶Only very rarely is multiple implementation inheritance actually useful. We allow multiple inheritance only when at most one of the base classes has an implementation; all other base classes must be pure interface classes tagged with the Interface suffix. Definition: Multiple inheritance allows a sub-class to have more than one base class. We distinguish between base classes that are pure interfaces and those that have an implementation. Pros: Multiple implementation inheritance may let you re-use even more code than single inheritance (see Inheritance). Cons: Only very rarely is multiple implementation inheritance actually useful. When multiple implementation inheritance seems like the solution, you can usually find a different, more explicit, and cleaner solution. Decision: Multiple inheritance is allowed only when all superclasses, with the possible exception of the first one, are pure interfaces. In order to ensure that they remain pure interfaces, they must end with the Interface suffix. Note: There is an exception to this rule on Windows. Interfaces link ▶Classes that satisfy certain conditions are allowed, but not required, to end with an Interface suffix. Definition: A class is a pure interface if it meets the following requirements: It has only public pure virtual ("= 0") methods and static methods (but see below for destructor). It may not have non-static data members. It need not have any constructors defined. If a constructor is provided, it must take no arguments and it must be protected. If it is a subclass, it may only be derived from classes that satisfy these conditions and are tagged with the Interface suffix. An interface class can never be directly instantiated because of the pure virtual method(s) it declares. To make sure all implementations of the interface can be destroyed correctly, they must also declare a virtual destructor (in an exception to the first rule, this should not be pure). See Stroustrup, The C++ Programming Language, 3rd edition, section 12.4 for details. Pros: Tagging a class with the Interface suffix lets others know that they must not add implemented methods or non static data members. This is particularly important in the case of multiple inheritance. Additionally, the interface concept is already well-understood by Java programmers. Cons: The Interface suffix lengthens the class name, which can make it harder to read and understand. Also, the interface property may be considered an implementation detail that shouldn't be exposed to clients. Decision: A class may end with Interface only if it meets the above requirements. We do not require the converse, however: classes that meet the above requirements are not required to end with Interface. Operator Overloading link ▶Do not overload operators except in rare, special circumstances. Definition: A class can define that operators such as + and / operate on the class as if it were a built-in type. Pros: Can make code appear more intuitive because a class will behave in the same way as built-in types (such as int). Overloaded operators are more playful names for functions that are less-colorfully named, such as Equals() or Add(). For some template functions to work correctly, you may need to define operators. Cons: While operator overloading can make code more intuitive, it has several drawbacks: It can fool our intuition into thinking that expensive operations are cheap, built-in operations. It is much harder to find the call sites for overloaded operators. Searching for Equals() is much easier than searching for relevant invocations of ==. Some operators work on pointers too, making it easy to introduce bugs. Foo + 4 may do one thing, while &Foo + 4 does something totally different. The compiler does not complain for either of these, making this very hard to debug. Overloading also has surprising ramifications. For instance, if a class overloads unary operator&, it cannot safely be forward-declared. Decision: In general, do not overload operators. The assignment operator (operator=), in particular, is insidious and should be avoided. You can define functions like Equals() and CopyFrom() if you need them. Likewise, avoid the dangerous unary operator& at all costs, if there's any possibility the class might be forward-declared. However, there may be rare cases where you need to overload an operator to interoperate with templates or "standard" C++ classes (such as operator<<(ostream&, const T&) for logging). These are acceptable if fully justified, but you should try to avoid these whenever possible. In particular, do not overload operator== or operator< just so that your class can be used as a key in an STL container; instead, you should create equality and comparison functor types when declaring the container. Some of the STL algorithms do require you to overload operator==, and you may do so in these cases, provided you document why. See also Copy Constructors and Function Overloading. Access Control link ▶Make data members private, and provide access to them through accessor functions as needed (for technical reasons, we allow data members of a test fixture class to be protected when using Google Test). Typically a variable would be called foo_ and the accessor function foo(). You may also want a mutator function set_foo(). Exception: static const data members (typically called kFoo) need not be private. The definitions of accessors are usually inlined in the header file. See also Inheritance and Function Names. Declaration Order link ▶Use the specified order of declarations within a class: public: before private:, methods before data members (variables), etc. Your class definition should start with its public: section, followed by its protected: section and then its private: section. If any of these sections are empty, omit them. Within each section, the declarations generally should be in the following order: Typedefs and Enums Constants (static const data members) Constructors Destructor Methods, including static methods Data Members (except static const data members) Friend declarations should always be in the private section, and the DISALLOW_COPY_AND_ASSIGN macro invocation should be at the end of the private: section. It should be the last thing in the class. See Copy Constructors. Method definitions in the corresponding .cc file should be the same as the declaration order, as much as possible. Do not put large method definitions inline in the class definition. Usually, only trivial or performance-critical, and very short, methods may be defined inline. See Inline Functions for more details. Write Short Functions link ▶Prefer small and focused functions. We recognize that long functions are sometimes appropriate, so no hard limit is placed on functions length. If a function exceeds about 40 lines, think about whether it can be broken up without harming the structure of the program. Even if your long function works perfectly now, someone modifying it in a few months may add new behavior. This could result in bugs that are hard to find. Keeping your functions short and simple makes it easier for other people to read and modify your code. You could find long and complicated functions when working with some code. Do not be intimidated by modifying existing code: if working with such a function proves to be difficult, you find that errors are hard to debug, or you want to use a piece of it in several different contexts, consider breaking up the function into smaller and more manageable pieces. Google-Specific Magic There are various tricks and utilities that we use to make C++ code more robust, and various ways we use C++ that may differ from what you see elsewhere. Smart Pointers link ▶If you actually need pointer semantics, scoped_ptr is great. You should only use std::tr1::shared_ptr under very specific conditions, such as when objects need to be held by STL containers. You should never use auto_ptr. "Smart" pointers are objects that act like pointers but have added semantics. When a scoped_ptr is destroyed, for instance, it deletes the object it's pointing to. shared_ptr is the same way, but implements reference-counting so only the last pointer to an object deletes it. Generally speaking, we prefer that we design code with clear object ownership. The clearest object ownership is obtained by using an object directly as a field or local variable, without using pointers at all. On the other extreme, by their very definition, reference counted pointers are owned by nobody. The problem with this design is that it is easy to create circular references or other strange conditions that cause an object to never be deleted. It is also slow to perform atomic operations every time a value is copied or assigned. Although they are not recommended, reference counted pointers are sometimes the simplest and most elegant way to solve a problem. cpplint link ▶Use cpplint.py to detect style errors. cpplint.py is a tool that reads a source file and identifies many style errors. It is not perfect, and has both false positives and false negatives, but it is still a valuable tool. False positives can be ignored by putting // NOLINT at the end of the line. Some projects have instructions on how to run cpplint.py from their project tools. If the project you are contributing to does not, you can download cpplint.py separately. Other C++ Features Reference Arguments link ▶All parameters passed by reference must be labeled const. Definition: In C, if a function needs to modify a variable, the parameter must use a pointer, eg int foo(int *pval). In C++, the function can alternatively declare a reference parameter: int foo(int &val). Pros: Defining a parameter as reference avoids ugly code like (*pval)++. Necessary for some applications like copy constructors. Makes it clear, unlike with pointers, that NULL is not a possible value. Cons: References can be confusing, as they have value syntax but pointer semantics. Decision: Within function parameter lists all references must be const: void Foo(const string &in, string *out); In fact it is a very strong convention in Google code that input arguments are values or const references while output arguments are pointers. Input parameters may be const pointers, but we never allow non-const reference parameters. One case when you might want an input parameter to be a const pointer is if you want to emphasize that the argument is not copied, so it must exist for the lifetime of the object; it is usually best to document this in comments as well. STL adapters such as bind2nd and mem_fun do not permit reference parameters, so you must declare functions with pointer parameters in these cases, too. Function Overloading link ▶Use overloaded functions (including constructors) only if a reader looking at a call site can get a good idea of what is happening without having to first figure out exactly which overload is being called. Definition: You may write a function that takes a const string& and overload it with another that takes const char*. class MyClass { public: void Analyze(const string &text); void Analyze(const char *text, size_t textlen); }; Pros: Overloading can make code more intuitive by allowing an identically-named function to take different arguments. It may be necessary for templatized code, and it can be convenient for Visitors. Cons: If a function is overloaded by the argument types alone, a reader may have to understand C++'s complex matching rules in order to tell what's going on. Also many people are confused by the semantics of inheritance if a derived class overrides only some of the variants of a function. Decision: If you want to overload a function, consider qualifying the name with some information about the arguments, e.g., AppendString(), AppendInt() rather than just Append(). Default Arguments link ▶We do not allow default function parameters, except in a few uncommon situations explained below. Pros: Often you have a function that uses lots of default values, but occasionally you want to override the defaults. Default parameters allow an easy way to do this without having to define many functions for the rare exceptions. Cons: People often figure out how to use an API by looking at existing code that uses it. Default parameters are more difficult to maintain because copy-and-paste from previous code may not reveal all the parameters. Copy-and-pasting of code segments can cause major problems when the default arguments are not appropriate for the new code. Decision: Except as described below, we require all arguments to be explicitly specified, to force programmers to consider the API and the values they are passing for each argument rather than silently accepting defaults they may not be aware of. One specific exception is when default arguments are used to simulate variable-length argument lists. // Support up to 4 params by using a default empty AlphaNum. string StrCat(const AlphaNum &a, const AlphaNum &b = gEmptyAlphaNum, const AlphaNum &c = gEmptyAlphaNum, const AlphaNum &d = gEmptyAlphaNum); Variable-Length Arrays and alloca() link ▶We do not allow variable-length arrays or alloca(). Pros: Variable-length arrays have natural-looking syntax. Both variable-length arrays and alloca() are very efficient. Cons: Variable-length arrays and alloca are not part of Standard C++. More importantly, they allocate a data-dependent amount of stack space that can trigger difficult-to-find memory overwriting bugs: "It ran fine on my machine, but dies mysteriously in production". Decision: Use a safe allocator instead, such as scoped_ptr/scoped_array. Friends link ▶We allow use of friend classes and functions, within reason. Friends should usually be defined in the same file so that the reader does not have to look in another file to find uses of the private members of a class. A common use of friend is to have a FooBuilder class be a friend of Foo so that it can construct the inner state of Foo correctly, without exposing this state to the world. In some cases it may be useful to make a unittest class a friend of the class it tests. Friends extend, but do not break, the encapsulation boundary of a class. In some cases this is better than making a member public when you want to give only one other class access to it. However, most classes should interact with other classes solely through their public members. Exceptions link ▶We do not use C++ exceptions. Pros: Exceptions allow higher levels of an application to decide how to handle "can't happen" failures in deeply nested functions, without the obscuring and error-prone bookkeeping of error codes. Exceptions are used by most other modern languages. Using them in C++ would make it more consistent with Python, Java, and the C++ that others are familiar with. Some third-party C++ libraries use exceptions, and turning them off internally makes it harder to integrate with those libraries. Exceptions are the only way for a constructor to fail. We can simulate this with a factory function or an Init() method, but these require heap allocation or a new "invalid" state, respectively. Exceptions are really handy in testing frameworks. Cons: When you add a throw statement to an existing function, you must examine all of its transitive callers. Either they must make at least the basic exception safety guarantee, or they must never catch the exception and be happy with the program terminating as a result. For instance, if f() calls g() calls h(), and h throws an exception that f catches, g has to be careful or it may not clean up properly. More generally, exceptions make the control flow of programs difficult to evaluate by looking at code: functions may return in places you don't expect. This causes maintainability and debugging difficulties. You can minimize this cost via some rules on how and where exceptions can be used, but at the cost of more that a developer needs to know and understand. Exception safety requires both RAII and different coding practices. Lots of supporting machinery is needed to make writing correct exception-safe code easy. Further, to avoid requiring readers to understand the entire call graph, exception-safe code must isolate logic that writes to persistent state into a "commit" phase. This will have both benefits and costs (perhaps where you're forced to obfuscate code to isolate the commit). Allowing exceptions would force us to always pay those costs even when they're not worth it. Turning on exceptions adds data to each binary produced, increasing compile time (probably slightly) and possibly increasing address space pressure. The availability of exceptions may encourage developers to throw them when they are not appropriate or recover from them when it's not safe to do so. For example, invalid user input should not cause exceptions to be thrown. We would need to make the style guide even longer to document these restrictions! Decision: On their face, the benefits of using exceptions outweigh the costs, especially in new projects. However, for existing code, the introduction of exceptions has implications on all dependent code. If exceptions can be propagated beyond a new project, it also becomes problematic to integrate the new project into existing exception-free code. Because most existing C++ code at Google is not prepared to deal with exceptions, it is comparatively difficult to adopt new code that generates exceptions. Given that Google's existing code is not exception-tolerant, the costs of using exceptions are somewhat greater than the costs in a new project. The conversion process would be slow and error-prone. We don't believe that the available alternatives to exceptions, such as error codes and assertions, introduce a significant burden. Our advice against using exceptions is not predicated on philosophical or moral grounds, but practical ones. Because we'd like to use our open-source projects at Google and it's difficult to do so if those projects use exceptions, we need to advise against exceptions in Google open-source projects as well. Things would probably be different if we had to do it all over again from scratch. There is an exception to this rule (no pun intended) for Windows code. Run-Time Type Information (RTTI) link ▶We do not use Run Time Type Information (RTTI). Definition: RTTI allows a programmer to query the C++ class of an object at run time. Pros: It is useful in some unittests. For example, it is useful in tests of factory classes where the test has to verify that a newly created object has the expected dynamic type. In rare circumstances, it is useful even outside of tests. Cons: A query of type during run-time typically means a design problem. If you need to know the type of an object at runtime, that is often an indication that you should reconsider the design of your class. Decision: Do not use RTTI, except in unittests. If you find yourself in need of writing code that behaves differently based on the class of an object, consider one of the alternatives to querying the type. Virtual methods are the preferred way of executing different code paths depending on a specific subclass type. This puts the work within the object itself. If the work belongs outside the object and instead in some processing code, consider a double-dispatch solution, such as the Visitor design pattern. This allows a facility outside the object itself to determine the type of class using the built-in type system. If you think you truly cannot use those ideas, you may use RTTI. But think twice about it. :-) Then think twice again. Do not hand-implement an RTTI-like workaround. The arguments against RTTI apply just as much to workarounds like class hierarchies with type tags. Casting link ▶Use C++ casts like static_cast(). Do not use other cast formats like int y = (int)x; or int y = int(x);. Definition: C++ introduced a different cast system from C that distinguishes the types of cast operations. Pros: The problem with C casts is the ambiguity of the operation; sometimes you are doing a conversion (e.g., (int)3.5) and sometimes you are doing a cast (e.g., (int)"hello"); C++ casts avoid this. Additionally C++ casts are more visible when searching for them. Cons: The syntax is nasty. Decision: Do not use C-style casts. Instead, use these C++-style casts. Use static_cast as the equivalent of a C-style cast that does value conversion, or when you need to explicitly up-cast a pointer from a class to its superclass. Use const_cast to remove the const qualifier (see const). Use reinterpret_cast to do unsafe conversions of pointer types to and from integer and other pointer types. Use this only if you know what you are doing and you understand the aliasing issues. Do not use dynamic_cast except in test code. If you need to know type information at runtime in this way outside of a unittest, you probably have a design flaw. Streams link ▶Use streams only for logging. Definition: Streams are a replacement for printf() and scanf(). Pros: With streams, you do not need to know the type of the object you are printing. You do not have problems with format strings not matching the argument list. (Though with gcc, you do not have that problem with printf either.) Streams have automatic constructors and destructors that open and close the relevant files. Cons: Streams make it difficult to do functionality like pread(). Some formatting (particularly the common format string idiom %.*s) is difficult if not impossible to do efficiently using streams without using printf-like hacks. Streams do not support operator reordering (the %1s directive), which is helpful for internationalization. Decision: Do not use streams, except where required by a logging interface. Use printf-like routines instead. There are various pros and cons to using streams, but in this case, as in many other cases, consistency trumps the debate. Do not use streams in your code. Extended Discussion There has been debate on this issue, so this explains the reasoning in greater depth. Recall the Only One Way guiding principle: we want to make sure that whenever we do a certain type of I/O, the code looks the same in all those places. Because of this, we do not want to allow users to decide between using streams or using printf plus Read/Write/etc. Instead, we should settle on one or the other. We made an exception for logging because it is a pretty specialized application, and for historical reasons. Proponents of streams have argued that streams are the obvious choice of the two, but the issue is not actually so clear. For every advantage of streams they point out, there is an equivalent disadvantage. The biggest advantage is that you do not need to know the type of the object to be printing. This is a fair point. But, there is a downside: you can easily use the wrong type, and the compiler will not warn you. It is easy to make this kind of mistake without knowing when using streams. cout << this; // Prints the address cout << *this; // Prints the contents The compiler does not generate an error because << has been overloaded. We discourage overloading for just this reason. Some say printf formatting is ugly and hard to read, but streams are often no better. Consider the following two fragments, both with the same typo. Which is easier to discover? cerr << "Error connecting to '" hostname.first << ":" hostname.second << ": " hostname.first, foo->bar()->hostname.second, strerror(errno)); And so on and so forth for any issue you might bring up. (You could argue, "Things would be better with the right wrappers," but if it is true for one scheme, is it not also true for the other? Also, remember the goal is to make the language smaller, not add yet more machinery that someone has to learn.) Either path would yield different advantages and disadvantages, and there is not a clearly superior solution. The simplicity doctrine mandates we settle on one of them though, and the majority decision was on printf + read/write. Preincrement and Predecrement link ▶Use prefix form (++i) of the increment and decrement operators with iterators and other template objects. Definition: When a variable is incremented (++i or i++) or decremented (--i or i--) and the value of the expression is not used, one must decide whether to preincrement (decrement) or postincrement (decrement). Pros: When the return value is ignored, the "pre" form (++i) is never less efficient than the "post" form (i++), and is often more efficient. This is because post-increment (or decrement) requires a copy of i to be made, which is the value of the expression. If i is an iterator or other non-scalar type, copying i could be expensive. Since the two types of increment behave the same when the value is ignored, why not just always pre-increment? Cons: The tradition developed, in C, of using post-increment when the expression value is not used, especially in for loops. Some find post-increment easier to read, since the "subject" (i) precedes the "verb" (++), just like in English. Decision: For simple scalar (non-object) values there is no reason to prefer one form and we allow either. For iterators and other template types, use pre-increment. Use of const link ▶We strongly recommend that you use const whenever it makes sense to do so. Definition: Declared variables and parameters can be preceded by the keyword const to indicate the variables are not changed (e.g., const int foo). Class functions can have the const qualifier to indicate the function does not change the state of the class member variables (e.g., class Foo { int Bar(char c) const; };). Pros: Easier for people to understand how variables are being used. Allows the compiler to do better type checking, and, conceivably, generate better code. Helps people convince themselves of program correctness because they know the functions they call are limited in how they can modify your variables. Helps people know what functions are safe to use without locks in multi-threaded programs. Cons: const is viral: if you pass a const variable to a function, that function must have const in its prototype (or the variable will need a const_cast). This can be a particular problem when calling library functions. Decision: const variables, data members, methods and arguments add a level of compile-time type checking; it is better to detect errors as soon as possible. Therefore we strongly recommend that you use const whenever it makes sense to do so: If a function does not modify an argument passed by reference or by pointer, that argument should be const. Declare methods to be const whenever possible. Accessors should almost always be const. Other methods should be const if they do not modify any data members, do not call any non-const methods, and do not return a non-const pointer or non-const reference to a data member. Consider making data members const whenever they do not need to be modified after construction. However, do not go crazy with const. Something like const int * const * const x; is likely overkill, even if it accurately describes how const x is. Focus on what's really useful to know: in this case, const int** x is probably sufficient. The mutable keyword is allowed but is unsafe when used with threads, so thread safety should be carefully considered first. Where to put the const Some people favor the form int const *foo to const int* foo. They argue that this is more readable because it's more consistent: it keeps the rule that const always follows the object it's describing. However, this consistency argument doesn't apply in this case, because the "don't go crazy" dictum eliminates most of the uses you'd have to be consistent with. Putting the const first is arguably more readable, since it follows English in putting the "adjective" (const) before the "noun" (int). That said, while we encourage putting const first, we do not require it. But be consistent with the code around you! Integer Types link ▶Of the built-in C++ integer types, the only one used is int. If a program needs a variable of a different size, use a precise-width integer type from , such as int16_t. Definition: C++ does not specify the sizes of its integer types. Typically people assume that short is 16 bits, int is 32 bits, long is 32 bits and long long is 64 bits. Pros: Uniformity of declaration. Cons: The sizes of integral types in C++ can vary based on compiler and architecture. Decision: defines types like int16_t, uint32_t, int64_t, etc. You should always use those in preference to short, unsigned long long and the like, when you need a guarantee on the size of an integer. Of the C integer types, only int should be used. When appropriate, you are welcome to use standard types like size_t and ptrdiff_t. We use int very often, for integers we know are not going to be too big, e.g., loop counters. Use plain old int for such things. You should assume that an int is at least 32 bits, but don't assume that it has more than 32 bits. If you need a 64-bit integer type, use int64_t or uint64_t. For integers we know can be "big", use int64_t. You should not use the unsigned integer types such as uint32_t, unless the quantity you are representing is really a bit pattern rather than a number, or unless you need defined twos-complement overflow. In particular, do not use unsigned types to say a number will never be negative. Instead, use assertions for this. On Unsigned Integers Some people, including some textbook authors, recommend using unsigned types to represent numbers that are never negative. This is intended as a form of self-documentation. However, in C, the advantages of such documentation are outweighed by the real bugs it can introduce. Consider: for (unsigned int i = foo.Length()-1; i >= 0; --i) ... This code will never terminate! Sometimes gcc will notice this bug and warn you, but often it will not. Equally bad bugs can occur when comparing signed and unsigned variables. Basically, C's type-promotion scheme causes unsigned types to behave differently than one might expect. So, document that a variable is non-negative using assertions. Don't use an unsigned type. 64-bit Portability link ▶Code should be 64-bit and 32-bit friendly. Bear in mind problems of printing, comparisons, and structure alignment. printf() specifiers for some types are not cleanly portable between 32-bit and 64-bit systems. C99 defines some portable format specifiers. Unfortunately, MSVC 7.1 does not understand some of these specifiers and the standard is missing a few, so we have to define our own ugly versions in some cases (in the style of the standard include file inttypes.h): // printf macros for size_t, in the style of inttypes.h #ifdef _LP64 #define __PRIS_PREFIX "z" #else #define __PRIS_PREFIX #endif // Use these macros after a % in a printf format string // to get correct 32/64 bit behavior, like this: // size_t size = records.size(); // printf("%"PRIuS"\n", size); #define PRIdS __PRIS_PREFIX "d" #define PRIxS __PRIS_PREFIX "x" #define PRIuS __PRIS_PREFIX "u" #define PRIXS __PRIS_PREFIX "X" #define PRIoS __PRIS_PREFIX "o" Type DO NOT use DO use Notes void * (or any pointer) %lx %p int64_t %qd, %lld %"PRId64" uint64_t %qu, %llu, %llx %"PRIu64", %"PRIx64" size_t %u %"PRIuS", %"PRIxS" C99 specifies %zu ptrdiff_t %d %"PRIdS" C99 specifies %zd Note that the PRI* macros expand to independent strings which are concatenated by the compiler. Hence if you are using a non-constant format string, you need to insert the value of the macro into the format, rather than the name. It is still possible, as usual, to include length specifiers, etc., after the % when using the PRI* macros. So, e.g. printf("x = %30"PRIuS"\n", x) would expand on 32-bit Linux to printf("x = %30" "u" "\n", x), which the compiler will treat as printf("x = %30u\n", x). Remember that sizeof(void *) != sizeof(int). Use intptr_t if you want a pointer-sized integer. You may need to be careful with structure alignments, particularly for structures being stored on disk. Any class/structure with a int64_t/uint64_t member will by default end up being 8-byte aligned on a 64-bit system. If you have such structures being shared on disk between 32-bit and 64-bit code, you will need to ensure that they are packed the same on both architectures. Most compilers offer a way to alter structure alignment. For gcc, you can use __attribute__((packed)). MSVC offers #pragma pack() and __declspec(align()). Use the LL or ULL suffixes a
Acknowledgments xiii Introduction xv 1. Making Games the Modular Way 1 1.1 Important Programming Concepts.....................................2 1.1.1 Manager and Controller Scripts...............................2 1.1.2 Script Communication.......................................3 1.1.3 Using the Singleton Pattern in Unity...........................5 1.1.4 Inheritance.................................................6 1.1.5 Where to Now?.............................................8 2. Building the Core Game Framework 9 2.1 Controllers and Managers............................................11 2.1.1 Controllers................................................11 2.1.2 Managers.................................................11 2.2 Building the Core Framework Scripts..................................11 2.2.1 BaseGameController.cs.....................................12 2.2.1.1 Script Breakdown................................14 viii Contents 2.2.2 Scene Manager.............................................17 2.2.2.1 Script Breakdown................................17 2.2.3 ExtendedCustomMonoBehavior.cs...........................19 2.2.4 BaseUserManager.cs........................................20 2.2.4.1 Script Breakdown................................22 2.2.5 BasePlayerManager.cs.......................................22 2.2.5.1 Script Breakdown................................23 2.2.6 BaseInputController.cs......................................24 2.2.6.1 Script Breakdown................................26 3. Player Structure 29 3.1 Game-Specific Player Controller......................................31 3.2 Dealing with Input..................................................32 3.3 Player Manager.....................................................35 3.3.1 Script Breakdown..........................................36 3.4 User Data Manager (Dealing with Player Stats Such as Health, Lives, etc.)....37 3.4.1 Script Breakdown..........................................39 4. Recipes: Common Components 41 4.1 Introduction.......................................................41 4.2 The Timer Class....................................................43 4.2.1 Script Breakdown..........................................45 4.3 Spawn Scripts......................................................48 4.3.1 A Simple Spawn Controller..................................49 4.3.1.1 Script Breakdown................................52 4.3.2 Trigger Spawner...........................................56 4.3.3 Path Spawner..............................................57 4.3.3.1 Script Breakdown................................61 4.4 Set Gravity.........................................................66 4.5 Pretend Friction—Friction Simulation to Prevent Slipping Around........66 4.5.1 Script Breakdown..........................................68 4.6 Cameras. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68 4.6.1 Third-Person Camera.......................................69 4.6.1.1 Script Breakdown................................71 4.6.2 Top-Down Camera.........................................74 4.6.2.1 Script Breakdown................................74 4.7 Input Scripts.......................................................75 4.7.1 Mouse Input...............................................75 4.7.1.1 Script Breakdown................................76 4.7.2 Single Axis Keyboard Input.................................78 4.8 Automatic Self-Destruction Script.....................................79 4.8.1 Script Breakdown..........................................79 4.9 Automatic Object Spinner............................................79 4.9.1 Script Breakdown..........................................80 ix Contents 4.10 Scene Manager.....................................................81 4.10.1 Script Breakdown..........................................82 5. Building Player Movement Controllers 85 5.1 Shoot ’Em Up Spaceship.............................................85 5.2 Humanoid Character................................................91 5.2.1 Script Breakdown..........................................96 5.3 Wheeled Vehicle...................................................106 5.3.1 Script Breakdown.........................................109 5.3.2 Wheel Alignment.........................................114 5.3.3 Script Breakdown.........................................116 6. Weapon Systems 121 6.1 Building the Scripts................................................122 6.1.1 BaseWeaponController.cs..................................122 6.1.1.1 Script Breakdown...............................127 6.1.2 BaseWeaponScript.cs......................................134 6.1.2.1 Script Breakdown...............................138 7. Recipe: Waypoints Manager 143 7.1 Waypoint System..................................................143 8. Recipe: Sound Manager 157 8.1 The Sound Controller...............................................158 8.1.1 Script Breakdown.........................................160 8.2 The Music Player...................................................163 8.2.1 Script Breakdown.........................................165 8.3 Adding Sound to the Weapons.......................................167 9. AI Manager 169 9.1 The AI State Control Script..........................................171 9.2 The Base AI Control Script. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .172 9.2.1 Script Breakdown.........................................185 9.3 Adding Weapon Control to the AI Controller..........................206 9.3.1 Script Breakdown.........................................210 10. Menus and User Interface 215 10.1 The Main Menu....................................................215 10.1.1 Script Breakdown.........................................223 10.2 In-Game User Interface.............................................231 x Contents 11. Dish: Lazer Blast Survival 233 11.1 Main Menu Scene..................................................235 11.2 Main Game Scene..................................................236 11.3 Prefabs...........................................................237 11.4 Ingredients........................................................238 11.5 Game Controller...................................................239 11.5.1 Script Breakdown.........................................243 11.6 Player Controller...................................................250 11.6.1 Script Breakdown.........................................253 11.7 Enemies..........................................................259 11.7.1 Script Breakdown.........................................260 11.8 Wave Spawning and Control........................................261 11.8.1 Script Breakdown.........................................263 11.9 Wave Properties...................................................265 11.10 Weapons and Projectiles. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..266 11.11 User Interface.....................................................266 11.11.1 Script Breakdown.........................................267 12. Dish: Metal Vehicle Doom 271 12.1 Main Menu Scene..................................................272 12.2 Main Game Scene..................................................272 12.2.1 Prefabs...................................................275 12.3 Ingredients........................................................275 12.3.1 Game Controller..........................................276 12.3.1.1 Script Breakdown...............................282 12.3.2 Race Controller...........................................291 12.3.2.1 Script Breakdown...............................297 12.3.3 Global Race Manager......................................306 12.3.3.1 Script Breakdown...............................311 12.3.4 Vehicle/Custom Player Control.............................318 12.3.4.1 Script Breakdown...............................327 12.3.5 User Interface.............................................344 13. Dish: Making the Game Tank Battle 345 13.1 Main Game Scene..................................................347 13.2 Prefabs...........................................................349 13.3 Ingredients........................................................349 13.4 Game Controller...................................................350 13.4.1 Script Breakdown.........................................356 13.5 Battle Controller...................................................361 13.5.1 Script Breakdown.........................................363 13.6 Global Battle Manager..............................................364 13.6.1 Script Breakdown.........................................368 13.7 Players............................................................373 13.7.1 Script Breakdown.........................................382 xi Contents 13.8 AI Chasing with SetAIChaseTargetBasedOnTag.cs.....................383 13.8.1 Script Breakdown.........................................385 14. Dish: Making the Game Interstellar Paranoids 389 14.1 Main Menu.......................................................392 14.2 Game Scenes......................................................392 14.3 Prefabs...........................................................393 14.3.1 Ingredients...............................................394 14.3.2 Game Controller..........................................395 14.3.2.1 Script Breakdown...............................401 14.3.3 Player Spaceship..........................................411 14.3.3.1 Script Breakdown...............................415 14.3.4 Enemies..................................................423 14.3.4.1 Script Breakdown...............................424 14.3.5 Waypoint Follower........................................426 14.3.5.1 Script Breakdown...............................427 Final Note 429 xiii I would like to thank my wife for all the encouragement, support, and nice cups of tea. I would also like to thank my mum and dad, my brother Steve, and everyone else who knows me. Sophie cat, be nice to the boys. Sincere thanks go to the many people who positively influence my life directly or indirectly: Michelle Ashton, Brian Robbins, George Bray, Nadeem Rasool, Christian Boutin, James and Anna, Rich and Sharon, Liz and Peter, Rob Fearon (the curator of all things shiny), everyone on Twitter who RTs my babble (you know who you are, guys!), Matthew Smith (the creator of Manic Miner), David Braben, Tōru Iwatani, and anyone who made Atari games in the 1980s. I would like to thank everyone at AK Peters/CRC Press for the help and support and for publishing my work. Finally, a massive thank you goes out to you for buying this book and for wanting to do something as cool as to make games. I sincerely hope this book helps your gamemaking adventures—feel free to tell me about them on Twitter @psychicparrot or drop by my website at http://www.psychicparrot.com. Acknowledgments xv As I was starting out as a game developer, as a self-taught programmer my skills took a while to reach a level where I could achieve what I wanted. Sometimes I wanted to do things that I just didn’t have yet the technical skills to achieve. Now and again, software packages came along that could either help me in my quest to make games or even make full games for me; complete game systems such as the Shoot ’Em-Up Construction Kit (aka SEUCK) from Sensible Software, Gary Kitchen’s GameMaker, or The Quill Adventure System could bring to life the kinds of games that went way beyond anything that my limited programming skills could ever dream of building. The downside to using game creation software was that it was tailored to create games within their chosen specific genre. If I wanted to do something outside of the limitations of the software, the source code was inaccessible and there was no way to extend or modify it. When that happened, I longed for a modular code-based system that I could plug together to create different types of games but modify parts of it without having to spend a lot of time learning how the entire system internals work—building block game development that I could actually script and modify if I needed to. After completing my first book, Game Development for iOS with Unity3D, I wanted to follow up by applying a modular style of game building to Unity3D that would provide readers with a highly flexible framework to create just about any kind of game by “plugging in” the different script components. My intention was to make a more technical second book, based on C# programming, that would offer extensibility in any direction a developer might require. In essence, what you are holding in your hands right now is a cookbook Introduction xvi Introduction for game development that has a highly flexible core framework for just about any type of game. A lot of the work I put in at the start of writing this book was in designing a framework that not only made sense in the context of Unity but also could easily cope with the demands of different genres. Prerequisites You can get up and running with the required software for the grand total of zero dollars. Everything you need can be downloaded free of charge with no catches. You may want to consider an upgrade to Unity Pro at some point in the future, to take advantage of some of its advanced features, but to get started all you need to do is grab the free version from the Unity website. Unity Free or Unity Pro (available from the Unity store at http://www.unity3d.com) Unity Free is completely free for anyone or any company making less than $100,000 per year—it may be downloaded for no charge at all, and you don’t even need a credit card. It’s a really sweet deal! We are talking about a fully functional game engine, ready to make 3D or 2D games that may be sold commercially or otherwise. There are no royalties to pay, either. Unity Pro adds a whole host of professional functionality to the engine, such as render culling and profiling. If you are a company with more than $100,000 per year of turnover, you will need a Pro license, but if you find that Unity Free doesn’t pack quite enough power, you may also want to consider going Pro. You can arrange a free trial of the Pro version right from the Unity website to try before you buy. If the trial licence runs out before you feel you know enough to make a purchase, contact Unity about extending it and they are usually very friendly and helpful about it (just don’t try using a trial license for 6 months at a time, as they may just figure it out!). C# programming knowledge Again, to reiterate this very important point, this is nota book about learning how to program. You will need to know some C#, and there are a number of other books out there for that purpose, even if I have tried to make the examples as simple as possible! This book is about making games, not about learning to program. What This Book Doesn’t Cover This is not a book about programming and it is not a book about the right or wrong way to do things. We assume that the reader has some experience with the C# programming language. I am a self-taught programmer, and I understand that there may well be better ways to do things. xvii Introduction This is a book about concepts, and it is inevitable that there will be better methods for achieving some of the same goals. The techniques and concepts offered in this book are meant to provide solid foundation, not to be the final word on any subject. It is the author’s intention that, as you gain your own experiences in game development, you make your own rules and draw your own conclusions. Additional material is available from the CRC Press Web site: http://www.crcpress. com/product/isbn/9781466581401. 1 1 Making Games the Modular Way When I first started making games, I would approach development on a project-to-project basis, recoding and rebuilding everything from scratch each time. As I became a professional developer, landing a job at a game development studio making browser-based games, I was lucky enough to work with a guy who was innovating the scene. He was a master at turning out great games (both visually and gameplay-wise) very quickly. One secret to his success lay in the development of a reusable framework that could easily be refactored to use on all of his projects. His framework was set up to deal with server communication, input handling, browser communication, and UI among other things, saving an incredible amount of time in putting together all of the essentials. By reusing the framework, it allowed more time for him and his team to concentrate on great gameplay and graphics optimization, resulting in games that, at the time, blew the competition away. Of course, the structure was tailored to how he worked (he did build it, after all), and it took me a while to get to grips with his style of development; but once I did, it really opened my eyes. From then on, I used the framework for every project and even taught other programmers how to go about using it. Development time was substantially reduced, which left more time to concentrate on making better games. This book is based on a similar concept of a game-centric framework for use with many different types of games, rather than a set of different games in different styles. The overall goal of this book is to provide script-based components that you can use within that framework to make a head start with your own projects in a way that reduces recoding, repurposing, or adaptation time. 2 1. Making Games the Modular Way In terms of this book as a cookbook, think of the framework as a base soup and the scripting components as ingredients. We can mix and match script components from different games that use the same framework to make new games, and we can share several of the same core scripts in many different games. The framework takes care of the essentials, and we add a little “glue” code to pull everything together the way we want it all to work. This framework is, of course, optional, but you should spend some time familiarizing yourself with it to help understand the book. If you intend to use the components in this book for your own games, the framework may serve either as a base to build your games on or simply as a tutorial test bed for you to rip apart and see how things work. Perhaps you can develop a better framework or maybe you already have a solid framework in place. If you do, find a way to develop a cleaner, more efficient framework or even a framework that isn’t quite so efficient but works better with your own code, and do it. In this chapter, we start by examining some of the major programming concepts used in this book and look at how they affect the design decisions of the framework. 1.1 Important Programming Concepts I had been programming in C# for a fairly long time before I actually sat down and figured out some of the concepts covered in this chapter. It was not because of any particular problem or difficulty with the concepts themselves but more because I had solved the problems in a different way that meant I had no real requirement to learn anything new. For most programmers, these concepts will be second nature and perhaps something taught in school, but I did not know how important they could be. I had heard about things like inheritance, and it was something I put in the to-do list, buried somewhere under “finish the project.” Once I took the time to figure them out, they saved me a lot of time and led to much cleaner code than I would have previously pulled together. If there’s something you are unsure about, give this chapter a read-through and see whether you can work through the ideas. Hopefully, they may save some of you some time in the long run. 1.1.1 Manager and Controller Scripts I am a strong believer in manager and controller scripts. I like to try and split things out into separate areas; for example, in the Metal Vehicle Doomgame, I have race controller scripts and a global race controller script. The race controller scripts are attached to the players and track their positions on the track, waypoints, and other relevant player-specific race information. The global race controller script talks to all the race controller scripts attached to the players to determine who is winning and when the race starts or finishes. By keeping this logic separate from the other game scripts and contained in their own controller scripts, it makes it easier to migrate them from project to project. Essentially, I can take the race controller and global race controller scripts out of the game and apply them to another game, perhaps one that features a completely different type of gameplay— for example, alien characters running around a track instead of cars. As long as I apply the correct control scripts, the race logic is in place, and I can access it in the new game. In the framework that this book contains, there are individual manager and controller scripts dealing with user data, input, game functions, and user interface. We look at those in detail in Chapter 2, but as you read this chapter, you should keep in mind the idea of separated scripts dedicated to managing particular parts of the game structure. It was 3 1.1 Important Programming Concepts important to me to design scripts as standalone so that they may be used in more than one situation. For example, our weapon slot manager will not care what kind of weapon is in any of the slots. The weapon slot manager is merely an interface between the player and the weapon, taking a call to “fire” and responding to it by telling the weapon in the currently selected weapon slot to fire. What happens on the player end will not affect the slot manager just as anything that happens with the weapon itself will not affect the slot manager. It just doesn’t care as long as your code talks to it in the proper way and as long as your weapons receive commands in the proper way. It doesn’t even matter what type of object the slot manager is attached to. If you decide to attach the weapon slot manager to a car, a boat, a telegraph pole, etc., it doesn’t really matter just as long as when you want them to fire, you use the correct function in the slot manager to get it to tell a weapon to fire. Since our core game logic is controlled by manager and controller scripts, we need to be a little smart about how we piece everything together. Some manager scripts may benefit from being static and available globally (for all other scripts to access), whereas others may be better attached to other scripts. We deal with these on a case-by-case basis. To get things started, we will be looking at some of the ways that these manager scripts can communicate with each other. As a final note for the topic in this section, you may be wondering what the difference is between managers and controllers. There really isn’t all that much, and I have only chosen to differentiate for my own sanity. I see controllers as scripts that are larger global systems, such as game state control, and managers as smaller scripts applied to gameObjects, such as weapon slot management or physics control. The terms are applied loosely, so don’t worry if there appear to be inconsistencies in the application of the term in one case versus another. I’ll try my best to keep things logical, but that doesn’t mean it’ll always make sense to everyone else! 1.1.2 Script Communication An important part of our manager- and component-based structures is how our scripts are going to communicate with each other. It is inevitable that we will need to access our scripts from a multitude of other areas of the game, which means we should try to provide interfaces that make the most sense. There are several different ways of communicating between scripts and objects in Unity: 1. Direct referencing manager scripts via variables set in the editor by the Inspector window. The easiest way to have your scripts talk to each other is to have direct references to them in the form of public variables within a class. They are populated in the Unity editor with a direct link to another script. Here is an example of direct referencing: public void aScript otherScript; In the editor window, the Inspector shows the otherScript field. We drag and drop an object containing the script component that we want to talk to. Within the class, function calls are made directly on the variable, such as otherScript.DoSomething(); 4 1. Making Games the Modular Way 2. GameObject referencing using SendMessage. SendMessage is a great way to send a message to a gameObject and call a function in one of its attached scripts or components when we do not need any kind of return result. For example, SomeGameObject.SendMessage("DoSomething"); SendMessage may also take several parameters, such as setting whether or not the engine should throw an error when there is no receiver, that is, no function in any script attached to the gameObject with a name matching the one in the SendMessage call. (SendMessageOptions). You can also pass one parameter into the chosen function just as if you were passing it via a regular function call such as SomeGameObject.SendMessage("AddScore",2); SomeGameObject.SendMessage("AddScore", SendMessageOptions.RequireReceiver); SomeGameObject.SendMessage("AddScore", SendMessageOptions.DontRequireReceiver); 3. Static variables. The static variable type is useful in that it extends across the entire system; it will be accessible in every other script. This is a particularly useful behavior for a game control script, where several different scripts may want to communicate with it to do things such as add to the player’s score, lose a life, or perhaps change a level. An example declaration of a static variable might be private static GameController aController; Although static variables extend across the entire program, you can have private and public static variables. Things get a little tricky when you try to understand the differences between public and private static types—I was glad to have friends on Twitter that could explain it all to me, so let me pass on what I was told: Public static A public static variable exists everywhere in the system and may be accessed from other classes and other types of script. Imagine a situation where a player control script needs to tell the game controller script whenever a player picks up a banana. We could deal with it like this: 1. In our gamecontroller.cs game controller script, we set up a public static: public static GameController gateway; 2. When the game controller (gamecontroller.cs) runs its Start() function, it stores a reference to itself in a public static variable like this: gateway = this; 3. In any other class, we can now access the game controller by referring to its type followed by that static variable (GameController.gateway) such as GameController.gateway.GotBanana(); 5 1.1 Important Programming Concepts Private static A private static variable exists within the class it was declared and in any other instances of the same class. Other classes/types of script will not be able to access it. As a working example, try to imagine that a script named player.cs directly controls player objects in your game. They all need to tell a player manager script when something happens, so we declare the player manager as a static variable in our player.cs script like this: private static PlayerManager playerManager; The playerManager object only needs to be set up once, by a single instance of the player class, to be ready to use for all the other instances of the same class. All player.cs scripts will be able to access the same instance of the PlayerManager. 4. The singleton design pattern. In the previous part of this section, we looked at using a static variable to share a manager script across the entire game code. The biggest danger with this method is that it is possible to create multiple instances of the same script. If this happens, you may find that your player code is talking to the wrong instance of the game controller. A singletonis a commonly used design pattern that allows for only one instance of a particular class to be instantiated at a time. This pattern is ideal for our game scripts that may need to communicate (or be communicated with) across the entire game code. Note that we will be providing a static reference to the script, exactly as we did in the “Static Variables” method earlier in this section, but in implementing a singleton class, we will be adding some extra code to make sure that only one instance of our script is ever created. 1.1.3 Using the Singleton Pattern in Unity It is not too difficult to see how useful static variables can be in communication between different script objects. In the public static example cited earlier, the idea was that we had a game controller object that needed to be accessed from one or more other scripts in our game. The method shown here was demonstrated on the Unity public wiki*by a user named Emil Johansen (AngryAnt). It uses a private static variable in conjunction with a public static function. Other scripts access the public function to gain access to the private static instance of this script, which is returned via the public function so that only one instance of the object will ever exist in a scene regardless of how many components it is attached to and regardless of how many times it is instantiated. A simple singleton structure: public class MySingleton { private static MySingleton instance; public MySingleton () *http://wiki.unity3d.com/index.php/Singleton. 6 1. Making Games the Modular Way { if (instance != null) { Debug.LogError ("Cannot have two instances of singleton."); return; } instance = this; } public static MySingleton Instance { get { if (instance == null) { new MySingleton (); } return instance; } } } The singleton instance of our script may be accessed anywhere, by any script, simply with the following syntax: MySingleton.Instance.MySingletonMember; 1.1.4 Inheritance Inheritanceis a complex concept, which demands some explanation here because of its key role within the scripts provided in this book. Have a read through this section, but don’t worry if you don’t pick up inheritance right away. Once we get to the programming, it will most likely become clear. The bottom line is that inheritance is used in programming to describe a method of providing template scripts that may be overridden, or added to, by other scripts. As a metaphor, imagine a car. All cars have four wheels and an engine. The types of wheels may vary from car to car, as will the engine, so when we say “this is a car” and try to describe how our car behaves, we may also describe the engine and wheels. These relationships may be shown in a hierarchical order: Car -Wheels -Engine Now try to picture this as a C# script: Car class Wheels function Engine function 7 1.1 Important Programming Concepts
EurekaLog 7.5 (18-August-2016) 1)..Important: Installation layout was changed. All packages now have version suffix (e.g. EurekaLogCore240.bpl). No files are copied to \bin folder of IDE. Run-time package (EurekaLogCore) is copied to Windows\System32 folder. Refer to help for more info. 2)....Added: RAD Studio 10.1 Berlin support 3)....Added: IDE F1 help integration (on CHM-based IDEs only, i.e. XE8+) 4)....Added "--el_injectjcl", "--el_createjcl", and "--el_createdbg" command-line options for ecc32/emake to inject JEDI/JCL debug info, create .jdbg file, and create .dbg file (Microsoft debug format). Later is supported when map2dbg.exe tool is placed in \Bin folder of EurekaLog installation (separate download is required) 5)....Added: Exception2HRESULT in EAppDLL to simplify developing DLLs with "DLL" profile 6)....Added: Use ShellExecute option for mailto send method 7)....Added: "Mandatory e-mail only when sending" option 8)....Added: Exception line highlighting in disassember view in EurekaLog exception dialog and Viewer 9)....Added: Detection/logging Delphi objects in disassembly view 10)..Added: Support for multi-monitor info 11)..Added: Support for detection of Windows 10 updates 12)..Added: OS edition detection 13)..Added: "User" and "Session" columns to processes list, processes list is also sorted by session first 14)..Added: Support for showing current user processes only 15)..Added: Expanding environment variables for "Support URL" 16)..Fixed: Range-check error on systems with MBCS ACP 17)..Fixed: 64-bit shared memory manager may not work 18)..Fixed: Possible "Unit XYZ was compiled with a different version of ABC" when using packages 19)..Fixed: FastMM shared MM compatibility 20)..Fixed: Minor bugs in stack tracing (which usually affected stacks for leaks) 21)..Fixed: Rare deadlocks in multi-threaded applications 22)..Fixed: Taking screenshot of minimized window 23)..Fixed: NT service may not log all exceptions 24)..Fixed: SSL port number for Bugzilla 25)..Fixed: Disabling "Activate Exception Filters" option was ignored 26)..Fixed: Missing FTP proxy settings 27)..Fixed: IntraWeb support is updated up to 14.0.64 28)..Fixed: Retrieving some process paths in processes list 29)..Fixed: CPU view rendering in EurekaLog exception dialog and Viewer 30)..Fixed: Some issues in naming threads 31)..Fixed: Removed exported helper _462EE689226340EAA982C5E8307B3F9E function (replaced with mapped file) 32)..Changed: Descriptions of EurekaLog project options now list corresponding property names of TEurekaModuleOptions class. 33)..Changed: Default template of HTML/web dialog now includes call stack by default 34)..Changed: EurekaLog 7 now can be installed over EurekaLog 6 automatically, with no additional actions/tools EurekaLog 7.4 (7.4.0.0), 26-January-2016 1)....Fixed: Performance issue in DLL exports debug information provider 2)....Fixed: Range-check error in Send dialog 3)....Fixed: Possible FPU control word unexpected change 4)....Fixed: JIRA sending to project with no version info 5)....Fixed: Viewer sorting affected by local region settings 6)....Fixed: Exception filters ignore settings for restart/terminate EurekaLog 7.3 Hotfix 2 (7.3.2.0), 20-October-2015 1)....Fixed: Added workaround for codegen bug in Delphi 7 (possibly - other), bug manifests itself as wrong date-time in reports or integer overflows 2)....Fixed: Some MAPI DLLs may not be loaded correctly 3)....Fixed: Handling SEC_I_INCOMPLETE_CREDENTIALS in SSPI code (added searching client certificate) 4)....Fixed: Range-check error when closing WinAPI dialog EurekaLog 7.3 Hotfix 1 (7.3.1.0), 2-October-2015 1)....Fixed: Long startup time on terminal services servers EurekaLog 7.3 (7.3.0.0), 24-September-2015 1)....Added: RAD Studio 10 Seattle support 2)....Added: Performance counters for run-time (internal logging with --el_debug) 3)....Fixed: spawned by ecc32/emake processes now start with the same priority 4)....Fixed: ThreadID = 0 in StandardEurekaNotify 5)....Fixed: Dialog auto-close timer may reset without user input 6)....Fixed: Possible hang when quickly loading/unloading EurekaLog-enabled DLL 7)....Fixed: Possible hang in COM DLLs 8)....Fixed: Removed some unnecessary file system access on startup 9)....Fixed: Possible wrong font size in EurekaLog tools 10)..Fixed: Ignore timeouts from Shell_NotifyIcon 11)..Fixed: Possible failure to handle/process stack overflow exceptions 12)..Changed: VCL/CLX/FMX now will assign Application.OnException handler when low-level hooks are disabled EurekaLog 7.2 Hotfix 6 (7.2.6.0), 14-July-2015 1)....Added: csoCaptureDelphiExceptions option 2)....Fixed: Handling of SECBUFFER_EXTRA in SSPI code 3)....Fixed: Several crashes in sending code for very old Delphi versions 4)....Fixed: Regression (from hotfix 5) crash in some IDEs EurekaLog 7.2 Hotfix 5 (7.2.5.0), 1-July-2015 1)....Added: HKCU\Software\EurekaLab\Viewer\4.0\UI\Statuses registry key to allow status customizations in Viewer 2)....Added: "Disable hang detection under debugger" option 3)....Fixed: Wrong button caption in standalone "Steps to reproduce" dialog 4)....Fixed: Wrong passing of Boolean parameters in JSON (affects JIRA) 5)....Fixed: Wrong sorting of BugID, Count and DateTime columns in Viewer 6)....Fixed: Empty "Count" field/column is now displayed as "1" in Viewer 7)....Fixed: Generic names with "," could not be decoded in Viewer 8)....Fixed: Updated Windows 10 detection for latest builds of Windows 10 9)....Fixed: Sleep and hybernation no longer trigger false-positive "application freeze" 10)..Fixed: Wrong function codes for hooking (affects ISAPI application type) 11)..Fixed: Wrong button caption in "Steps to Reproduce" dialog 12)..Fixed: Crash when taking snapshot of some proccesses by Threads Snapshot tool 13)..Fixed: Minor improvements in leak detection EurekaLog 7.2 Hotfix 4 (7.2.4.0), 10-June-2015 1)....Added "ECC32TradeSpeedForMemory" option - defaults to 0/False, could be changed to 1 via Custom/Manual tab. This option will switch from fast-methods to slower methods, but which take less memory. Use 0 (default) for small projects, use 1 for large projects (if ecc32 runs out of memory). 2)....Added: --el_DisableDebuggerPresent command-line option for compatibility with 3rd party debuggers (AQTime, etc.) 3)....Added: AQTime auto-detect 4)....Fixed: Performance optimizations 5)....Fixed: Windows 8+ App Menu shortcuts 6)....Fixed: Unmangling on x64 EurekaLog 7.2 Hotfix 3 (7.2.3.0), 20-May-2015 1)....Added: Support for token auth in Bugzilla (latest 4.x builds) 2)....Added: Support for API key auth in Bugzilla (5.x) 3)....Added: Support for /EL_DisableMemoryFilter command-line option 4)....Added: Asking e-mail when user switches to "details" from MS Classic without entering e-mail 5)....Fixed: Compatibility issues with older Bugzilla versions (3.x) 6)....Fixed: Passing settings between dialogs 7)....Fixed: "Ask for steps to reproduce" dialog is now DPI-aware 8)....Fixed: Silently ignore and fix invalid values in project options EurekaLog 7.2 Hotfix 2 (7.2.2.0), 30-April-2015 1)....Fixed: Confusing message in Manage tool when using with Trial/Pro 2)....Fixed: Range check error in processes information for x64 machines (affects startup of any EurekaLog-enabled module) 3)....Fixed: Auto-detect personality by project extension if --el_mode switch is missing 4)....Fixed: More details for diagnostic sending 5)....Fixed: Wrong settings for MAP files in C++ Builder 6)....Fixed: Wrong code page was used to decode ANSI bug reports 7)....Fixed: Attaching .PAS files instead of .OBJ in C++ Builder 2006+ Pro/Trial EurekaLog 7.2 Hotfix 1 (7.2.1.0), 3-April-2015 1)....Fixed: Wrong float-str convertion when ThousandSeparator is '.' EurekaLog 7.2 (7.2.0.0), 1-April-2015 1)....Important: TEurekaLogV7 component was renamed to TEurekaLogEvents. Please, update your projects by renaming or recreating the component 2)....Important: File layout was changed for BDS 2006+. Delphi and C++ Builder files are now located in StudioNum folders instead of old DelphiNum and CBuilderNum folders. Update your search paths if needed 3)....Added: Major improvements in DumpAllocationsToFile function (EMemLeaks unit) 4)....Added: MemLeaksSetParentBlock, MemLeaksOwn, EurekaTryGetMem functions (EMemLeaks unit) 5)....Added: Improvements for call stack of dynarrays/strings allocations (leaks) 6)....Added: "Elem size" when reporting leaks in dynarrays 7)....Added: Streaming unpacked debug info into temporal files instead of memory - this greatly reduces run-time application memory usage at cost of slightly slower exception processing. This also reduces memory footprint for ecc32/emake 8)....Added: Showing call stacks for 2 new types of fatal memory errors 9)....Added: EMemLeaks._ReserveOutOfMemory to control reserve size of out of memory errors (default is 50 Mb) 10)..Added: "MinLeaksLimitObjs" option (EMemLeaks unit) 11)..Added: Fatal memory problem now pauses all threads in application 12)..Added: Fatal memory problem now change thread name (to simplify debugging) 13)..Added: boPauseELThreads and boDoNotPauseELServiceThread options (currently not visible in UI) 14)..Added: Support for texts collections out of default path 15)..Added: Support for relative file paths to text collections and external settings 16)..Added: Support for environment variables in project option's paths 17)..Added: Support for relative file paths and environment variables for events and various module paths 18)..Added: Logging in Manage tool 19)..Added: Windows 10 version detection 20)..Added: Stack overflow tracing 21)..Added: Major improvements in removal of recursive areas from call stack 22)..Added: Statistics collection 23)..Added: Support for uploading multiple files in JIRA 24)..Added: EResLeaks improvements (new funcs: ResourceAdd, ResourceDelete, ResourceName; support for realloc-like functions) 25)..Fixed: Added workaround for bug in JIRA 5.x 26)..Fixed: Rare EurekaLog internal error 27)..Fixed: Ignored unhandled thread exceptions (when EurekaLog is disabled) now triggers default OS processing (WER) 28)..Fixed: Irnored exceptions (via per-exception/events) now bring up default RTL handler 29)..Fixed: Format error in Viewer 30)..Fixed: Leak of EurekaLog exception information object 31)..Fixed: Wrong chaining exceptions inside GetMem/FreeMem 32)..Fixed: Memory leak after low-level unhook of function 33)..Fixed: Re-parenting after ReallocMem 34)..Fixed: Editing SMTP server options 35)..Fixed: SMTP server not using real user e-mail in FROM field 36)..Fixed: Some multi-threading crashes 37)..Fixed: Fixed crashes in Manage tool 38)..Fixed: Range-check error in Viewer 39)..Fixed: EurekaLog error dialog appearing under other windows 40)..Fixed: AV when parsing TDS (emake/C++ Builder specific) 41)..Fixed: Unable to build call stacks for other threads due to insufficient rights 42)..Fixed: Version checks for BugZilla and JIRA 43)..Fixed: Not catching out-of-module AVs when "Capture exceptions only from current module" option is checked 44)..Fixed: Checking for remaining exceptions at shutdown (C++ Builder specific, AcquireExceptionObject returns wrong info) 45)..Fixed: "get call stack of ... threads" / "suspend ... threads" options (avoid rare multithreading race conditions) 46)..Fixed: Crash when naming thread without EurekaLog thread info 47)..Fixed: Detection of immediate caller for memory funcs 48)..Fixed: Non-working Assign for options 49)..Fixed: Handling of explicitly chained exceptions 50)..Fixed: Various exception/threading fixes for MS debug provider 51)..Fixed: Processing hardware unhandled exceptions (QC #55007) 52)..Fixed: Unchecking dialog options when export/import 53)..Fixed: BSTR leak 54)..Fixed: JIRA decimal separator bug 55)..Changed: Now unhandled exceptions will be handled by EurekaLog even if EurekaLog is disabled in the thread - only global EurekaLog-enabled status is respected 56)..Changed: Viewer version now matches version of EurekaLog 57)..Changed: DeleteServiceFilesOption now always False by default 58)..Changed: Speed improvements for known memory leaks (reserved leaks) 59)..Changed: Improved logging for sending 60)..Changed: Switching to detailed mode without entering (mandatory) e-mail: now EL will not block this 61)..Changed: .ToString for exception info now uses compact stack formatter 62)..Removed: Custom field editor (replaced it with link to "Custom" page) 63)..Removed: EurekaLog 7 no longer could be installed over EurekaLog 6. Manage tool from EurekaLog 7 will no longer work with EurekaLog 6. EurekaLog 7.1 update 1 (7.1.1.0), 19-October-2014 1)....Added: "Send in separated thread" option 2)....Added: Hang detection will now use Wait Chain Traversal (WCT) on Vista+ systems to detect deadlocks in any EurekaLog-enabled threads 3)....Added: OS install language and UI language fields in bug report 4)....Fixed: Viewer is not able to decrypt reports with generics 5)....Fixed: EVariantTypeCastError in Viewer when changing status of some bug reports 6)....Fixed: EcxInvalidDataControllerOperation in Viewer 7)....Fixed: Stack overflow at run-time for certain combination of project options 8)....Fixed: BMP re-draw bug in UI dialogs 9)....Fixed: Rogue "corrupted" error message for valid ZIPs of certain structure 10)..Fixed: Various range check errors in Viewer 11)..Fixed: Possible encoding errors for non-ASCII reports in Viewer on certain environments 12)..Fixed: Wrong count in Viewer when importing reports without proper "count" field 13)..Fixed: Duplicate reports may appear in bug report file when "Do not save duplicate errors" option is checked 14)..Fixed: False-positive detection of some virtual machines 15)..Fixed: Processing of exceptions from message handlers during message pumping cycle inside exception dialogs 16)..Fixed: Access Violation if exception dialog was terminated by exception 17)..Fixed: Hardware exceptions from unit's initialization/finalization may be unprocessed 18)..Changed: "VIEW" action for Viewer now will open ALL bug reports inside bug report file; reports will not be merged by BugID. "IMPORT" action remains the same: duplicate reports are merged, "count" is increased 19)..Changed: Charset field in bug report now shows both charset and code page EurekaLog 7.1 (7.1.0.00), 23-September-2014 1)....Added: XE7 support 2)....Added: XE6 support 3)....Added: New DLL demo 4)....Added: Custom profiles are now shown in "Application type" combo-box 5)....Added: Non-empty "steps to reproduce" will be added to existing bug tracker issues with empty "steps to reproduce" 6)....Added: Support for custom fields in FogBugz (API version 8 and above) 7)....Added: Support for unsequenced line numbers in PDB/DBG files (--el_source switch) 8)....Fixed: XML bug report were generated wrong 9)....Fixed: Strip relocations code for Win64 10)..Fixed: EurekaLog conditional symbols removed improperly when deactivating EurekaLog 11)..Fixed: Sending reports to non-default port numbers (affects web-based methods) 12)..Fixed: SSL validation check may reject valid SSL certificate (SMTP Client/Server) 13)..Fixed: SSL errors may be not reported 14)..Fixed: Viewer did not consider empty bug reports as corrupted 15)..Fixed: "DLL" profile now can be used with packages properly 16)..Fixed: Few rare memory leaks 17)..Fixed: Possible deadlock when using MS debug info provider 18)..Fixed: C++ Builder project files was saved incorrectly (RAD Studio 2007+) 19)..Fixed: "Show restart checkbox after N errors" counts handled exceptions 20)..Fixed: IDE expert's DPR parser (added support for multi-part idents) 21)..Fixed: Rare access violation in hook code 22)..Fixed: Thread handle leaks (added _NotifyThreadGone/_CleanupFinishedThreads functions to be called manually - only when low-level hooks are not installed) 23)..Fixed: EurekaLog's installer hang 24)..Fixed: Bug in object/class validation 25)..Fixed: Bug when using TThreadEx without EurekaLog 26)..Fixed: Leaks detection may not work with certain combination of options 27)..Fixed: Deadlock in some cases when using EurekaLog threading option set to "enabled in RTL threads, disabled in Windows threads". 28)..Changed: TEurekaExceptionInfo.CallStack will be nil until exception is actually raised 29)..Changed: FogBugz and BugZilla: changed bugs identification within project (to allow two bugs exists with same BugID in different projects) 30)..Changed: Blocked manual creation/destruction of ExceptionManager class and EurekaExceptionInfo 31)..Changed: ECC32/EMAKE runs from IDE without changing priority, added ECC32PriorityClass option 32)..Improved: Minor help and text improvements EurekaLog 7.0.07 Hotfix 2 (7.0.7.2), 11-December-2013 1)....Fixed: Delphi compiler code generation bug (Delphi 2007 and below) 2)....Fixed: Code hooks may rarely be set incorrectly (code stub relocation fails) 3)....Fixed: Win64 call stacks functions now work more similar to 32 bit call stacks EurekaLog 7.0.07 Hotfix 1 (7.0.7.1), 2-December-2013 1)....Added: Alternative caption for e-mail input control when e-mail is mandatory 2)....Fixed: Rare range check error in WinAPI visual dialogs 3)....Fixed: Wrong error detection for OnExceptionError event 4)....Fixed: Wrong TResponce processing 5)....Fixed: Problems with encrypted call stack decoding 6)....Fixed: OnPasswordRequest event may have no effect EurekaLog 7.0.07 (7.0.7.0), 25-November-2013 1)....Added: Ability to use Assign between call stack and TStrings 2)....Added: 64-bit disassembler 3)....Added: Support for variables and relative file paths in "Additional Files" send option 4)....Added: --el_source switch for ecc32/emake compilers 5)....Added: support for post-processing non-Embarcadero executables 6)....Added: EOTL.pas unit for better OmniThreadLibrary integration 7)....Added: RAD Studio XE5 support 8)....Added: New "Capture call stacks of EurekaLog-enabled threads" option 9)....Added: "Deferred call stacks" option for 64-bit 10)..Added: Copy report to clipboard now copies both report text and report file 11)..Added: "AttachBothXMLAndELReports" option to include both .elx and .el files into bug report 12)..Added: EMemLeaks.MemLeaksErrorsToIgnore option to exclude certain memory errors from being considered as fatal 13)..Added: Call stack with any encrypted entry will be fully encrypted now 14)..Added: Option to exclude certain memory errors from being considered as fatal (EMemLeaks.MemLeaksErrorsToIgnore) 15)..Added: New "HTTP Error Code" option for all web-based dialogs (CGI, ISAPI, etc.) 16)..Added: Support for Unicode in Simple MAPI send method (requires Windows 8 or latest Microsoft Office) 17)..Added: New value for call stack detalization option (show any addresses, including those not belonging to any executable module) 18)..Fixed: Wrong JSON escaping for strings (affects JIRA send method) 19)..Fixed: Range-check error in Viewer when viewing bug reports with high addresses 20)..Fixed: Selecting Win32 service application type is no longer resets to custom/unsupported 21)..Fixed: Possible hang when testing dialogs from EurekaLog project options dialog 22)..Fixed: Rare resetting of some options when saving .eof file 23)..Fixed: Exception pointer could be removed from call stack due to debug details filtering 24)..Fixed: Rare case when LastThreadException returned nil while there was active thread exception 25)..Fixed: Rare case when ShowLastThreadException do nothing 26)..Fixed: Improved compatibility for OmniThreadLibrary and AsyncCalls 27)..Fixed: Included fix for QC #72147 28)..Fixed: 64-bit MS Debug Info Provider (please, re-setup cache options using configuration dialog) 29)..Fixed: "Deferred call stacks" option failed to capture call stack when exception is re-raised between threads 30)..Fixed: "Deferred call stacks" option may produce cutted call stack in rare cases 31)..Fixed: Several minor call stacks improvements and optimizations 32)..Fixed: Several 64-bit Pointer Integer convertion issues 33)..Fixed: Multi-threading deadlock issue 34)..Fixed: Black screenshots in 64 bit applications 35)..Fixed: Copying to clipboard hot-key was registered globally 36)..Fixed: Shell (mailto) send method may fail (64 bit) 37)..Fixed: Possible wrong file paths for attaches in (S)MAPI send methods 38)..Fixed: Environment variables were not expanded in MAPI send method 39)..Fixed: (non-Unicode IDE) EurekaLog is not activated when application started from folder with Unicode characters 40)..Fixed: Encrypted call stacks may be encrypted partially by EurekaLog Viewer in rare cases 41)..Fixed: Crash when sending leak report with visual progress dialog (only some IDEs are affected) 42)..Fixed: ecc32/emake could not see external configuration file with the same name as project (e.g. Project1.eof for Project1.dpr) 43)..Fixed: Added missed RTL implementation for ExternalProps in Delphi 6 (affects Mantis sending) 44)..Fixed: IDE crash when switching to threads window 45)..Changed: Removed temporal solution which was used before option to defer call stack creation was introduced 46)..Changed: "Default EurekaLog state in new threads" option is changed from Boolean flag into enum. You need to re-setup this option 47)..Changed: Disable EurekaLog for thread when creating call stack or handle exception - this increases stability and performance 48)..Changed: LastException property is remove from exception manager as not thread safe. Use LastThreadException property instead 49)..Changed: Lock/Unlock from thread manager and exception manager are removed to avoid deadlocks 50)..Changed: ThreadsSnapshot tool now tries to capture call stack without injecting DLL 51)..Changed: Build events now runs with CREATE_NO_WINDOW flag (console window is hidden) 52)..Improved: More articles in help EurekaLog 7.0.06 (7.0.6.0), 1-June-2013 1)....Added: Experimental 64 bit C++ Builder support 2)....Added: New tab in EurekaLog project options: "External tools" 3)....Added: Option to catch all IDE errors (to debug your own IDE packages) 4)....Added: Option to catch only exceptions from current module 5)....Added: Option to defer building call stack 6)....Added: RAD Studio XE4 support 7)....Added: Support for AppWave 8)....Fixed: Fixed event handlers declarations for the EurekaLog component 9)....Fixed: Infinite recursive calls when using ToString from EndReport event handler 10)..Fixed: UPX compatibility issue 11)..Fixed: Range check errors for system error codes 12)..Fixed: Rare IDE stack overflow 13)..Fixed: JIRA unit was not added automatically 14)..Fixed: EurekaLog no longer tries to check for leaks when memory manager filter is disabled 15)..Fixed: Possible deadlock on shutdown with freeze checks active 16)..Fixed: Issues with settings dialog and Win32 Service application type 17)..Fixed: ThreadSnapshot tool was not able to take snapshots of Win64 processes 18)..Fixed: WCT is disabled for leaks 19)..Fixed: TContext declarations for Win64 20)..Fixed: Check for updates now correctly sets time of last check 21)..Fixed: (Win64) Several Pointer Integer convertion errors 22)..Fixed: Internal error when exception info object was deleted while it was still used by SysUtils exception object 23)..Fixed: Semeral problems with "EurekaLog look & feel" style for EurekaLog error dialog 24)..Fixed: Using text collection resets exception filters 25)..Fixed: Rare access violation if registering event handlers is placed too early 26)..Fixed: SMTP RFC date formatting 27)..Fixed: Rare empty call stack bug 28)..Fixed: Hang detection was not working if EurekaLog was disabled in threads 29)..Fixed: AV for double-free TEncoding 30)..Changed: ecc32/emake no longer alters arguments for dcc32/make unless new options --el_add_default_options is specified 31)..Changed: Save/load options methods was moved to TEurekaModuleOptions class 32)..Changed: Saving options to EOF file now adds hidden options and removes obsolete options (only when compatibility mode is off) 33)..Changed: Compiling installed packages now silently ignores EurekaLog instead of showing "File is in use" error message 34)..Improved: More readable disk/memory sizes in bug reports 35)..Improved: More descriptive settings dialog when using external configuration 36)..Improved: ThreadSnapshot tool now aquired DEBUG priviledge for taking snapshot. This allows it to bypass security access checks when opening target process. 37)..Improved: Changed BugID default generation to include error code for OS errors and error message for DB errors 38)..Improved: Mantis API (WSDL) was updated to the latest version (1.2.14) 39)..Improved: IntraWeb compatibility (old and new versions) 40)..Improved: COM applications compatibility 41)..Improved: Build events now accept shell commands 42)..Improved: More articles in help EurekaLog 7.0.05 (7.0.5.0), 7-February-2013 1)....Added: JIRA support 2)....Added: Virtual machine detection (new field in bug reports) 3)....Fixed: "Use Main Module options" option was loading empty options for some cases 4)....Fixed: Wrong record declarations for Simple MAPI on Win64 5)....Fixed: Performance issues with batch module options updating 6)....Fixed: Wrong leaks report with both MemLeaks/ResLeaks options active 7)....Fixed: Wrong info for nested exceptions in some cases 8)....Fixed: AV under debugger for Win64 (added support for _TExitDllException) 9)....Fixed: Wrong record declarations for process/thread info on Win64 10)..Fixed: Support for FinalBuilder on XE2/XE3 with spaces in file paths 11)..Fixed: Rare double-free of module information (ModuleInfoList) 12)..Fixed: Rare External Exception C000071C on shutdown (only under debuggger) 13)..Fixed: Added large addresses support in Viewer 14)..Fixed: Counter options in memory leaks category is now working properly 15)..Fixed: Rare range-check error in TEurekaModulesList.AddModuleFromFileName 16)..Fixed: FTP force directories dead lock 17)..Fixed: Fixed wrong index being used when clearing compatibility mode (EurekaLog project options dialog) 18)..Fixed: Default thread state do not affect main thread now 19)..Fixed: Sometimes wrong thread may be used when altering EurekaLog active state for external thread 20)..Fixed: Wrong DNS lookup on ANSI 21)..Fixed: Problems with IDE expert and projects on network paths 22)..Fixed: Added support for arguments in URLs (HTTP sending) 23)..Fixed: Possible deadlock in multithreaded applications 24)..Fixed: Problems with unicode characters in project files on non-Unicode IDEs 25)..Fixed: Infinite recursive calls when using ToString from EndReport event handler 26)..Fixed: Win64 GetCaller now returns pointer to call instruction, not return address 27)..Improved: Standalone Editor do not force save/load folder by default 28)..Improved: DLL profile now can use additional application type hooks automatically 29)..Improved: EurekaLog now able to work with read-only projects (see help for more info) EurekaLog 7.0.04 (7.0.4.0), 2-December-2012 1)....Added: Support for nested exceptions in DLLs 2)....Fixed: Options bug in EurekaLogSendEmail function 3)....Fixed: Weird behaviour for steps to reproduce and custom fields 4)....Fixed: Installation for single personality (BDS) 5)....Fixed: Range check error in EModules 6)....Fixed: Bug in exception destroy hook 7)....Fixed: OnExceptionNotify event is no longer called for handled exceptions without option checked 8)....Fixed: DEP checks on startup no longer cause exception 9)....Fixed: Invalid declaration for MS Debug API 10)..Fixed: OLE mode change error for "Test" send button 11)..Fixed: Fixes for multiply loading of the same DLL 12)..Fixed: Removed PNG compression from icons (tools) 13)..Fixed: Range-check error in dialogs with EurekaLog style enabled 14)..Fixed: Send progress dialog may keep busy forever processing window messages (message flood from rapid application GUI updates) 15)..Fixed: Thread pausing options now work correctly 16)..Improved: New features in exception filters - marking exceptions as "expected", filtering by properties (RTTI) 17)..Improved: Recovery from memory errors without debugging memory manager 18)..Improved: Viewer's password edit now hides password with asterisks 19)..Updated: Changed names of .inc files to avoid name conflicts with other libraries 20)..Updated: Help EurekaLog 7.0.03 (7.0.3.0), 6-October-2012 1)....Fixed: Removed some consts keywords for event handlers, so now C++ Builder can alter arguments (this change may require you to adjust your custom code) 2)....Fixed: Fallback code for false-positive results on memory probing 3)....Fixed: Range check errors in SSL/TLS implementation 4)....Fixed: "EurekaLog is not active" error message during send testing 5)....Fixed: Incorrect memory probing when DEP is off (old systems) 6)....Fixed: Installation of 64-bit BPLs 7)....Fixed: Dialog preview 8)....Fixed: Win64 fixes for XE3 9)....Fixed: Support for project groups (mixed project types) 10)..Fixed: Windows 2000 hooks compatibility 11)..Fixed: mailto double quotes escaping 12)..Fixed: Simple MAPI WOW compatibility 13)..Fixed: Simple MAPI modal issues 14)..Fixed: Various range check errors 15)..Changed: Removed minor version number from program group name 16)..Updated: Help EurekaLog 7.0.02 hot-fix 1 (7.0.2.1), 12-September-2012 1)....Fixed: Range check error in Viewer 2)....Fixed: Bug in hooking code EurekaLog 7.0.02 (7.0.2.0), 11-September-2012 1)....Added: Improved memory problems detection 2)....Added: Minor IDE Expert usability improvements 3)....Added: Auto-size feature for detailed error dialog 4)....Added: Workaround for QC #106935 5)....Added: Workaround for bug in InvokeRegistry (SOAP/Mantis) 6)....Fixed: Nested OS exceptions 7)....Fixed: Multiply Win64 fixes 8)....Fixed: Compatibility mode fixes 9)....Fixed: Altered behaviour of "Add BugID/Date/ComputerName" options 10)..Fixed: Blank screenshots 11)..Fixed: Check file for corruptions 12)..Fixed: Viewer is unable to decrypt certain bug reports 13)..Fixed: Internal DoNoTouch option now works for post-processing and condtionals 14)..Fixed: Possible out of memory error for "Do not store class/procedure names" option 15)..Fixed: EurekaLog did not properly install itself when there is only Delphi installed, but no C++ Builder of the same version (or visa versa) 16)..Fixed: Wrong argument for OnRaise event 17)..Fixed: Handling memory errors in initialization/finalization sections 18)..Fixed: Updating steps to reproduce and user e-mail in bug report 19)..Fixed: Proper Success/Failure for some errors during SMTP send 20)..Added: Workaround for wrong GUI fonts 21)..Added: Delphi XE3 support 22)..Added: Individual options for each exception EurekaLog 7.0.01 (7.0.1.0), 28-June-2012 1)....Added: New "Modal window" option (MS Classic and EurekaLog dialogs) 2)....Added: New "Owned window" option (MS Classic and EurekaLog dialogs) 3)....Added: New "Catch EurekaLog IDE Expert errors" option 4)....Added: Backup memory manager to recover from critical errors 5)....Added: Alternative methods to provide additional features when memory filter is not set 6)....Fixed: Contains fixes from hotfixes 1-3 7)....Fixed: Performance improvements 8)....Fixed: Improved IDE Expert's speed, stability and compatibility with other 3rd party extensions 9)....Fixed: MS Classic dialog size adjustments for large "click here" translations 10)..Fixed: Fixed resetting few EurekaLog project options to defaults 11)..Fixed: Multiplying exception filters when options are assigned (for example: when switching to/from "Custom" page in project options) 12)..Fixed: (Compatibility mode) Fixed send options merging 13)..Fixed: Updated help EurekaLog 7.0 hot-fix 3 (7.0.0.273), 20-June-2012 --------------------------- 1)....Fixed: ERangeError in EResLeaks (THandle Integer) 2)....Fixed: C++ Builder breakpoints for large projects 3)....Fixed: Help (updates policy changed) 4)....Fixed: Text collections applying 5)....Fixed: Build events are now called for unlocked file 6)....Fixed: Proper handling of C++ Builder project options files from Delphi code (settings editor and IDE expert) 7)....Fixed: Terminate/Checked sub-option for MS Classic dialog 8)....Fixed: Confusing message for already post-processed executables 9)....Fixed: Access violation for some EurekaLog IDE menu items when no project was loaded 10)..Fixed: Invoking help for "Variables" window 11)..Fixed: EurekaLog Viewer version info 12)..Fixed: Events in components 13)..Added: Retry option for "Sorry, you must close all running IDE instances before installation" 14)..Added: Italian translation 15)..Added: Actual change log is now included into installer 16)..Added: Even more setup logging 17)..Added: New help articles (recompilation and manual installation) EurekaLog 7.0 hot-fix 2 (7.0.0.261), 10-June-2012 --------------------------- 1)....Fixed: Wrong version info reporting to IDE 2)....Added: Workaround for Delphi 2005 TListView bug 3)....Added: Workaround for possible invalid FPU state in exception handlers 4)....Added: Missed declarations for ExceptionLog (compatibility mode) 5)....Fixed: Work for unsaved projects 6)....Added: Escaping for '--' in options (confuses IDE's XML parsing) 7)....Added: Storing thread's class/name in call stack for terminated threads 8)....Added: More setup logging 9)....Fixed: Help (broken links) 10)..Added: "Upgrade to EurekaLog 7" help topic 11)..Fixed: Clean up installed files EurekaLog 7.0 hot-fix 1 (7.0.0.256), 6-June-2012 --------------------------- 1)....Fixed: Invalid Format() arguments in ELogBuilder. EurekaLog 7.0, 1-June-2012 --------------------------- 1)....Improved: Main change - EurekaLog's core was rewritten (refactored) to allow more easy modification and remove hacks. 2)....Improved: New plugin-like architecture now allows you to exclude unused code. 3)....Improved: New plugin-like architecture now allows you to easily extends EurekaLog. 4)....Improved: Greatly extended documentation. 5)....Improved: Installer is now localized. 6)....Improved: Greatly speed ups creation of minimal bug report (with most information disabled). 7)....Changed: EurekaLog's root IDE menu was relocated to under Tools and extended with new items. 8)....Added: New examples. 9)....Added: New tools (address lookup, error lookup, threads snapshot, standalone settings editor). 10)..Added: Support for DBG/PDB formats of debug information (including symbol server support and auto-downloading). 11)..Added: Support for madExcept debug information (experimental). 12)..Added: WER (Windows Error Reporting) support. 13)..Added: Full unicode support. 14)..Added: Professional and Trial editions: added source code (interface sections only) 15)..Improved: Dialogs - new options and new customization possibilities: 16)..Added: All GUI dialogs: ability to test dialog directly from configuration dialog by displaying a sample window with currently specified settings. 17)..Improved: All GUI dialogs: dialogs are DPI-awared now (auto-scale for different DPI). 18)..Added: MessageBox dialog: added detailed mode (shows a compact call stack). 19)..Added: MessageBox dialog: added ability for asking a send consent. 20)..Added: MessageBox dialog: added support to switch to "native" message box for application. 21)..Added: MS Classic dialog: added control over "user e-mail" edit's visibility. 22)..Added: MS Classic dialog: added ability to personalize dialog view with application's name and icon. 23)..Added: MS Classic dialog: added ability to show terminate/restart checkbox initially checked. 24)..Added: EurekaLog dialog: added ability to personalize dialog view with application's name and icon. 25)..Added: EurekaLog dialog: added ability to show terminate/restart checkbox initially checked. 26)..Added: EurekaLog dialog: added ability to switch back to non-detailed view. 27)..Added: WEB dialog: added new tags to customize bug report page. 28)..Improved: WEB dialog: improved support for unicode and charset. 29)..Added: New dialog type: RTL dialog. 30)..Added: New dialog type: console output. 31)..Added: New dialog type: system logging. 32)..Added: New dialog type: Windows Error Reporting. 33)..Improved: Sending - new options and new customization possibilities: 34)..Added: All send methods: added ability to setup multiply send methods. 35)..Added: All send methods: added ability to change send method order. 36)..Added: All send methods: added separate settings for each send method. 37)..Added: All send methods: ability to test send method directly from configuration dialog by sending a demo bug report. 38)..Added: SMTP client send method: added SSL support. 39)..Added: SMTP client send method: added TLS support. 40)..Added: SMTP client send method: added option for using real e-mail address. 41)..Added: SMTP server send method: added option for using real e-mail address. 42)..Added: HTTP upload send method: added support for custom backward feedback messages. 43)..Added: FTP upload send method: added creating folders on FTP (like remote ForceDirectories). 44)..Added: Mantis send method: added API support (MantisConnect, out-of-the-box since Mantis 1.1.0, available as add-on for previous versions). 45)..Added: Mantis send method: added support for custom "Count" field. 46)..Added: Mantis send method: added options for controlling duplicates. 47)..Added: Mantis send method: added support for SSL/TLS. 48)..Added: FogBugz send method: added API support (out-of-the-box since ForBugz 7, available as add-on for FogBugz 6). 49)..Added: FogBugz send method: EurekaLog will update "Occurrences" field (count of bugs). 50)..Added: FogBugz send method: EurekaLog will respect "Stop reporting" option (BugzScout's setting). 51)..Added: FogBugz send method: EurekaLog will respect "Scout message" option (BugzScout's setting). 52)..Added: FogBugz send method: EurekaLog will store client's e-mail as issue's correspondent. 53)..Added: FogBugz send method: added options for controlling duplicates. 54)..Added: FogBugz send method: added support for "Area" field. 55)..Added: FogBugz send method: added support for SSL/TLS. 56)..Added: BugZilla send method: added API support. 57)..Added: BugZilla send method: added support for custom "Count" field. 58)..Added: BugZilla send method: added options for controlling duplicates. 59)..Added: BugZilla send method: added support for SSL/TLS. 60)..Added: New send method: Shell (mailto protocol). 61)..Added: New send method: extended MAPI. 62)..Added: Support for separate code and debug info injection. 63)..Added: Ability to use custom units before EurekaLog's units. 64)..Added: Support for external configuration file in IDE expert. 65)..Added: Now EurekaLog stores only those project options which are different from defaults (to save disk space and reduce noise in project file). 66)..Added: Now EurekaLog stores project options sorted (alphabet order). 67)..Added: Separate settings for saving modules and processes lists to bug report. 68)..Added: Support for taking screenshots of multiply monitors. 69)..Added: More screenshot customization options. 70)..Added: More control over bug report's file names. 71)..Added: New environment variables. 72)..Added: Deleting .map file after compilation. 73)..Added: Support for different .dpr and .dproj file names. 74)..Improved: memory leaks detection feature - new options and new customization possibilities: 75)..Added: Ability to track memory problems without activation of leaks checking. 76)..Added: Support for sharing memory manager. 77)..Added: Support for tracking leaks in applications built with run-time packages. 78)..Added: Option to zero-fill freed memory. 79)..Added: Option to enable leaks detection only when running under debugger. 80)..Added: Option for manual activation control for leaks detection (via command-line switches). 81)..Added: Option to select stack tracing method for memory problems. 82)..Added: Option to trigger memory leak reporting only for large leaked memory's size. 83)..Added: Option to control limit of number of reported leak. 84)..Added: CheckHeap function to force check of heap's consistency. 85)..Added: DumpAllocationsToFile function to save information about allocated memory to log file. 86)..Added: Registered leaks feature. 87)..Added: Run-time control over memory leak registering. 88)..Added: New recognized leak type: String (both ANSI and Unicode are supported). 89)..Added: Memory features support for C++ Builder. 90)..Added: Resource leaks detection feature. 91)..Improved: Compilation speed increased. 92)..Added: Support for generics in debug information. 93)..Added: Chained/nested exceptions support. 94)..Added: Wait Chain Traversal support. 95)..Added: Support for named threads. 96)..Added: Additional information for threads in call stack. 97)..Improved: EurekaLog Viewer Tool: 98)..Added: Now Viewer has its own help file 99)..Added: Viewer now supports a FireBird based database on local file or remote server. 100).Added: You can have more that one user account for FireBird based database. 101).Added: Viewer now can be launched in View mode (Viewer can be configured to any DB or View mode). 102).Added: Viewer's database now supports storing files, associated with the report (you can also add and remove files manually). 103).Added: Viewer supports "Import" and "View" commands for report files. 104).Improved: Extended support for more log formats (XML, packed ELF, etc). 105).Added: Columns in report's list now can be configured (you can hide and show them). 106).Added: There are a plenty of new columns added to report's list. 107).Added: Ability of auto-download reports from e-mail account. 108).Improved: printing - now you can print the entire report (including screenshots). Old behaviour of printing just one tab (call stack only, for example) also remains. 109).Added: Viewer can now have more that one run-time instance . 110).Added: File import status dialog is now configurable (you can disable it, if you want to). 111).Added: There is a preview area for screenshots, available in reports. 112).Improved: Now Viewer is more Vista-friendly (i.e. file associations are managed in HKCU, rather that in HKLM, storing configuration in user's Application Data, etc, etc). 113).Added: Report's list now supports multi-select, so operations can be performed on many reports at time. 114).Added: There are plenty of new command line abilities, like specifying several files and new switches. 115).Improved: Bunch of minor changes and improvements. WARNING: -------- There are many changes in this release. See the "Changed from the old 6.x version" help topic for further information! EurekaLog 7 also have "EurekaLog 6 backward compatibility mode". Please, refer to help file for more information. We also have the detailed "Upgrade guide" in our help system.
C# 访问Oracle示例+PL/SQL+存储过程+触发器 完整示例 测试可用 --PL/SQL基础1 declare begin dbms_output.('不输出不换行'); dbms_output.put_line('输出并换行'); end; --PL/SQL基础2 declare dig number(20,2); begin select avg(price) into dig from products; dbms_output.put_line('电子产品的平均价格是'||dig); end; --PL/SQL基础3 根据产品编号获得产品对象 --pname products.name%type; pname变量的类型与products.name列的类型一样 declare pid constant products.id%type:=1; --定义常量,初值1 pname products.name%type; pdate products.adddate%type; begin --pid:=1; select name,adddate into pname,pdate from products where id=pid; dbms_output.put_line('产品名称是:'||pname||',日期'||pdate); end; --PL/SQL基础4 根据产品编号获得产品对象 --obj products%rowtype; obj与products表的单行类型一样,可以通过点运算取值obj.price declare obj products%rowtype; begin select * into obj from products where id=&编号; dbms_output.put_line('产品名称是:'||obj.name||',价格:'||obj.price); end; --PL/SQL基础5 条件if declare vid products.id%type; vprice products.price%type; begin vid:=&编号; select price into vprice from products where id=vid; if vprice100 and vprice<=1000 then dbms_output.put_line('价格在100—1000之间'); else dbms_output.put_line('价格在1000以上'); end if; end; --PL/SQL基础5 多条件case begin case '&等级' when 'A' then dbms_output.put_line('优秀'); when 'B' then dbms_output.put_line('合格'); when 'C' then dbms_output.put_line('不合格'); end case; end; select id, name, typeid, price, adddate from products create table students( Id int primary key, sex int ) insert into students select 1,1 from dual union select 2,0 from dual union select 3,1 from dual union select 4,0 from dual union select 5,1 from dual insert into students(Id) values(6) select * from students; select translate(translate('1心1意 3心2意','1','一'),'3','三') from dual; select id,nvl(translate(translate(sex,1,'女'),0,'男'),'未知') from students; select id,case as 性别 from( sele

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