Converting from a std::string to bool

Question

What is the best way to convert a std::string to bool? I am calling a function that returns either \"0\" or \"1\", and I need a clean solution for turning this into a boole

Answer 1

Write a free function:

bool ToBool( const std::string & s ) {
   return s.at(0) == '1';
}

This is about the simplest thing that might work, but you need to ask yourself:

• what should an empty string return? the version above throws an exception
• what should a character other than '1' or '0' convert to?
• is a string of more than one character a valid input for the function?

I'm sure there are others - this is the joy of API design!