Objectifies functions lol

objectify.js

'use strict';

var args = function (fun) {
  var str = fun.toString().split("\n")[0];
  return str.substring(str.indexOf("(")+1, str.indexOf(")")).split(",").map(function (x) { return x.trim(); });
};

var objectify = function (fun) {
  if (typeof fun !== 'function') throw new Error(fun + " is not a function.");
  // could extend so it also accepts an array or arguments
  return function (obj) {
    var call_args = args(fun).map(function (arg) {
      return obj[arg];
    });
    return fun.apply(this, call_args);
  };
};

// let add = (a = 3, b, c) => a + b + c;
// var oadd = objectify(add);
// console.log(oadd({a: 1, b: 2, c: 3}));