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分享如何写一个指针的定义，指针指向类的成员函数
//问题：如何写一个指针类型的定义，个指针类型是一个指向类模板中（泛型）类中定义的类成员函数的指针。
template < typename T1 ,typename T2>
class temp_test
{
private:
T1 m1;
public:
T2 m2;
void fun(void);
} ;
template <typename T1 , typename T2> void temp_test<typename T1 , typename T2>::fun(void)
{
}
//如下尝试均失败
//typedef void (temp_test<typename T1 , typename T2>::* p_template_class_fun)(void); //error C2065: 'T1' : undeclared identifier
//typedef void (temp_test::* p_template_class_fun)(void); //error C2955: 'temp_test' : use of class template requires template argument list
...全文
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unituniverse2 2014-04-24
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没法编辑。。。。
template < typename T1 ,typename T2>
using p_template_class_fun = void (temp_test<T1, T2>::*)(void);
p_template_class_fun<int, float> p1 = &temp_test<int, float>::fun;
unituniverse2 2014-04-24
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template < typename T1 ,typename T2>
using p_template_class_fun = void (temp_test<T1, T2>::* p_template_class_fun)(void);
p_template_class_fun<int, float> p1 = &temp_test<int, float>::fun;
john 2014-04-24
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不对。……....
赵4老师 2014-04-24
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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 |
//+------------------+-----------------------------------------+---------------+
赵4老师 2014-04-24
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//| ->* | Dereference pointer to class member | Left to right |
john 2014-04-24
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解决了!!!
unituniverse2 2014-04-24
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当然没用
说”有用“只是限于研究原理、学习用，除非你想自己写个编译器。否则这样的代码在其他编译器上不一定能正常工作的
john 2014-04-24
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有用。
实际问题是来自一个开源项目源代码中演绎出来的。QP：http://www.state-machine.com/qp/
unituniverse2 2014-04-24
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这个东西在vc里的实现，32位下面是48位的，64位下面是80位的，还有你这样去搞成员地址是不对的。
成员函数/变量指针实际上不是指针（即使是做为类型也不是）。编译器的具体实现就不要纠结了吧，没用的
john 2014-04-24
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原因找到了。是“优化”搞的鬼。去掉优化就正确了。
顺答复#8楼，纯属蹂躏C++玩。没别的意思。
ri_aje 2014-04-24
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都有 auto 和 decltype 了还受这罪？
john 2014-04-24
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请教，[为何执行结果获得的是一样的地址？
