Question

This piece of code fails to compile and I don’t know if it is because it can not be done, lambdas do not inherit from binary_function, or it is just that I’m getting the syntax wrong

#include <functional>

int main(int argc, const char *argv[])
{
   auto lambda = [](int x, int y) -> int { return x + y; };
   auto sumFive = std::bind1st(lambda, 5); 

   return 0;
}

Answer 1

Use:

auto sumFive = std::bind(lambda, 5, std::placeholders::_1);

Please forget entirely about bind1st and binary_function, etc. Those were crutches in the old C++ because of the lack of lambdas and variadic templates. In C++11, use std::function and std::bind.