为什么以下代码不能编译,当我在A类中的构造函数之前删除显式关键字时,它编译?
使用Visual Studio 2013:
enum E { e1_0, e1_1 };
template<typename T>
struct A
{
A() {}
explicit A(unsigned long) {}
A(T) {}
};
struct B
{
B() {}
B(E) {}
};
void F(B) {};
void F(A<short>) {};
void test()
{
F(e1_0);
}
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错误:
1>------ Build started: Project: exp_construct_test, Configuration: Debug Win32 ------
1> exp_construct_test.cpp
1>e:\exp_construct_test\exp_construct_test.cpp(23): error C2668: 'F' : ambiguous call to overloaded function
1> e:\exp_construct_test\exp_construct_test.cpp(19): could be 'void F(A<short>)'
1> e:\exp_construct_test\exp_construct_test.cpp(18): or 'void F(B)'
1> while trying to …Run Code Online (Sandbox Code Playgroud)