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赵4老师 2015-10-23
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《深度探索C++对象模型》
《C++反汇编与逆向分析技术揭秘》
fefe82 2015-10-23
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指向成员的指针与普通指针有一个很大的不同，就是他解引用的时候需要两个操作数（一个是指向成员的指针，另一个是类的实例），而普通指针值只需要一个（即指针本身）。于是出现了 ->* 与 .* 来在左侧提供类的实例，右边放指向成员指针。
但是取地址的时候，无论指向成员的指针还是普通指针，都只需要一个操作数。于是大家共用了 & 操作符。
fly_dragon_fly 2015-10-23
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C++这么多年了, 也许连创始人也不记得当年发生了什么, 现在找一个说法与当时可能已经相差甚远. 我提种说法, 觉得可以就信之, 不可以再看其它人的解释
取成员地址,不需要实例, 比如class A{ public: void fun(){} }; 可以直接&A::fun, 如果要写成->&的形式, 就需要A*pa, pa->&才行, 直接A->这种语法也没有
ipqtjmqj 2015-10-23
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为什么只有->*和.*呢, 很好理解,
因为 ->和.原来后面跟的都是具体相对地址的变量, 而不是指针.
*运算符通常后面跟个指针, 返回指向的变量, 这与->和.的要求相符.
&运算符通常后面跟个变量, 返回内容为该变量地址的指针, 这与-和.的要求不符.
srxumin 2015-10-22
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TO 赵老师：我知道没有->&运算符的，我只是想知道为什么没有，谢谢了。
TO Saleayas：为什么用&号时&Class::Member就放在前面，而用*号时Class->*Member就放在后面？你不觉得对于一个初学者，很容易在记忆上造成混乱吗？
既然容易造成混乱，C++的创始人肯定也知道的，所以想我知道它们宁愿造成混乱也要把*号放在中间的原因
赵4老师 2015-10-22
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//C++ Operators
// Operators specify an evaluation to be performed on one of the following:
// One operand (unary operator)
// Two operands (binary operator)
// Three operands (ternary operator)
// The C++ language includes all C operators and adds several new operators.
// Table 1.1 lists the operators available in Microsoft C++.
// Operators follow a strict precedence which defines the evaluation order of
//expressions containing these operators. Operators associate with either the
//expression on their left or the expression on their right; this is called
//“associativity.” Operators in the same group have equal precedence and are
//evaluated left to right in an expression unless explicitly forced by a pair of
//parentheses, ( ).
// Table 1.1 shows the precedence and associativity of C++ operators
// (from highest to lowest precedence).
//
//Table 1.1 C++ Operator Precedence and Associativity
// The highest precedence level is at the top of the table.
//+------------------+-----------------------------------------+---------------+
//| Operator | Name or Meaning | Associativity |
//+------------------+-----------------------------------------+---------------+
//| :: | Scope resolution | None |
//| :: | Global | None |
//| [ ] | Array subscript | Left to right |
//| ( ) | Function call | Left to right |
//| ( ) | Conversion | None |
//| . | Member selection (object) | Left to right |
//| -> | Member selection (pointer) | Left to right |
//| ++ | Postfix increment | None |
//| -- | Postfix decrement | None |
//| new | Allocate object | None |
//| delete | Deallocate object | None |
//| delete[ ] | Deallocate object | None |
//| ++ | Prefix increment | None |
//| -- | Prefix decrement | None |
//| * | Dereference | None |
//| & | Address-of | None |
//| + | Unary plus | None |
//| - | Arithmetic negation (unary) | None |
//| ! | Logical NOT | None |
//| ~ | Bitwise complement | None |
//| sizeof | Size of object | None |
//| sizeof ( ) | Size of type | None |
//| typeid( ) | type name | None |
//| (type) | Type cast (conversion) | Right to left |
//| const_cast | Type cast (conversion) | None |
//| dynamic_cast | Type cast (conversion) | None |
//| reinterpret_cast | Type cast (conversion) | None |
//| static_cast | Type cast (conversion) | None |
//| .* | Apply pointer to class member (objects) | Left to right |
//| ->* | Dereference pointer to class member | Left to right |
//| * | Multiplication | Left to right |
//| / | Division | Left to right |
//| % | Remainder (modulus) | Left to right |
//| + | Addition | Left to right |
//| - | Subtraction | Left to right |
//| << | Left shift | Left to right |
//| >> | Right shift | Left to right |
//| < | Less than | Left to right |
//| > | Greater than | Left to right |
//| <= | Less than or equal to | Left to right |
//| >= | Greater than or equal to | Left to right |
//| == | Equality | Left to right |
//| != | Inequality | Left to right |
//| & | Bitwise AND | Left to right |
//| ^ | Bitwise exclusive OR | Left to right |
//| | | Bitwise OR | Left to right |
//| && | Logical AND | Left to right |
//| || | Logical OR | Left to right |
//| e1?e2:e3 | Conditional | Right to left |
//| = | Assignment | Right to left |
//| *= | Multiplication assignment | Right to left |
//| /= | Division assignment | Right to left |
//| %= | Modulus assignment | Right to left |
//| += | Addition assignment | Right to left |
//| -= | Subtraction assignment | Right to left |
//| <<= | Left-shift assignment | Right to left |
//| >>= | Right-shift assignment | Right to left |
//| &= | Bitwise AND assignment | Right to left |
//| |= | Bitwise inclusive OR assignment | Right to left |
//| ^= | Bitwise exclusive OR assignment | Right to left |
//| , | Comma | Left to right |
//+------------------+-----------------------------------------+---------------+
Saleayas 2015-10-22
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&Class::Member
