Using lambdas to generate lambdas.

lambdagenerators.hpp

#include <iostream>
#include <cassert>
#include <cmath>
int main()
{
  auto add  = [](auto x) { return [x](auto y) { return x + y; }; };
  auto pyth = [](auto x) { return [x](auto y) { return std::sqrt(x * x + y * y); }; };
  
  // are lambdas really fucking dumb?!?!
  auto add4 = add(4);
  auto addhalf = add(0.5);
  auto val6 = add4(2);
  auto val10 = add4(6);
  auto val15 = addhalf(1);
  
  auto pyth3 = pyth(3);
  auto val5 = pyth3(4);
  
  assert(val6 == 6);
  assert(val10 == 10);
  assert(val15 == 1.5);
  assert(val5 == 5);
  std::cout << "success!\n";
  return 0;
}