• See the blog post.
• Expression parsing in C++ with Dijkstra's Shunting-yard algorithm.
• Original version by Jessee Brown.

#include <iostream>
#include "shunting-yard.h"

int main() {
  std::map<std::string, double> vars;
  vars["pi"] = 3.14;
  std::cout << calculator::calculate("-pi+1", &vars) << std::endl;
  return 0;
}

• See test-shunting-yard.cpp.

• Unary operators. +, -
• Binary operators. +, -, /, +, <<, >>
• Map of variable names.

To add a binary operator,

1. Update the operator precedence map in calculator::calculate.
2. Add the computation to calculator::consume.