C++

23.7    Custom Literals

A user-defined literal is a custom suffix that can be appended to strings or sequences of digits. The suffix is a regular identifier. Users can define how a literal is interpreted by overriding a member of the new operator"" family. The family members differ in the parameter types of the respective operator""().

// https://godbolt.org/z/cjx49ef19namespace my {  Complex operator"" _i(const char*); // 0+ni  Complex operator"" _j(long double); // n+0i  Puzzle operator"" _puzzle(const char*, size_t);}using namespace my;Complex imag4 = 4_i;      // operator"" _i(const char*)Complex real3 = 3.331_j;  // operator"" _j(long double)Puzzle p1 = "oXo"         // operator"" _puzzle(const char*, size_t)            "XoX"_puzzle;  

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