Overload Resolution between func(const char*) and func(std::string&)-CodePudding

I have two functions:

int func(const std::string& str) { return func(str.c_str()); }
int func(const char* str) { /* ... */ }

If I call func(std::string("abcdef")); first function (const std::string&) call recursively itself, not a const char* because type conversion.

I can use Forward Declaration:

int func(const char* str);
int func(const std::string& str) { return func(str.c_str()); }
int func(const char* str) { /* ... */ }

or change functions definitions order:

int func(const char* str) { /* ... */ }
int func(const std::string& str) { return func(str.c_str()); }

and it works.

But is there another way for Overload Resolution?

CodePudding user response：

To exclude implicit type conversions from overload resolution you should make template functions that only accept exact type matches. (SFINAE) e.g.

template<typename type_t> 
auto func(const type_t& string) 
    -> std::enable_if_t<std::is_same_v<std::string,type_t>,int> 
{ 
}

This will resolve to a function returning an int only when std::string and type_t exactly match (without conversions)