How Can I Correctly Use `char*` Keys in a C `std::map`?

Understanding std::map with char* Keys

In C programming, using char as a key in a std::map can lead to unexpected issues. This article delves into the challenges associated with using char keys and explores a solution to overcome these difficulties.

The code sample provided in the question faces issues because the std::map compares the raw pointers rather than the null-terminated strings they reference. To resolve this issue, it is necessary to incorporate a comparison functor into the map.

Consider the following code snippet as a solution:

struct cmp_str
{
    bool operator()(char const *a, char const *b) const
    {
        return std::strcmp(a, b) < 0;
    }
};

map<char *, int, cmp_str> g_PlayerNames;

By defining and utilizing this comparison functor, the std::map is furnished with the ability to compare the null-terminated strings pointed to by the char* keys, ensuring proper functioning and resolving the issue encountered in the provided code.

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