(C++) operator!

 

operator! (pronounced 'logical not operator') is an operator to do a logical not on a boolean. In other words: !true is false, and !false is true.

 

The example code below asserts that a std::string is not empty, before returning the first character of it.

 

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#include <cassert> #include <string> char GetFirstChar(const std::string& s) {   assert(!s.empty());   return s[0]; } int main() {   assert(GetFirstChar("Bilderbikkel")=='B'); }