C++编译期的类型测试

编译期的类型测试

一、使用模板特化机制

如比较两个类型是否一致：

VC8及以后版本支持了type traits机制：

add_const Class            // Makes const type from type. add_cv Class               // Makes const/volatile type from type. add_pointer Class          // Makes pointer to type from type. add_reference Class        // Makes reference to type from type. add_volatile Class         // Makes volatile type from type. aligned_storage Class      // Makes suitably aligned type. alignment_of Class         // Gets alignment of type. common_type Class conditional Class decay Class enable_if Class extent Class               // Gets an array dimension. has_nothrow_assign Class   // Tests whether the type does not throw on assign. has_nothrow_constructor Class // Tests whether the type does not throw on default construction. has_nothrow_copy Class     // Tests whether the type does not throw on copy construction. has_nothrow_copy_constructor Class has_nothrow_default_constructor Class has_trivial_assign Class   // Tests whether the type has trivial assign. has_trivial_constructor Class // Tests whether the type has trivial default constructor. has_trivial_copy Class     // Tests whether the type has trivial copy constructor. has_trivial_copy_constructor Class has_trivial_default_constructor Class has_trivial_destructor Class // Tests whether the type has trivial destructor. has_virtual_destructor Class // Tests whether the type has virtual destructor. is_abstract Class          // Tests whether the type is abstract class. is_arithmetic Class        // Tests whether the type is arithmetic. is_array Class