ein/index.js

Easy way to deal with decimals

var binds = {
  "floor": function (digits) {
    var den = Math.pow(10, digits == null ? 0 : digits);
    return Math.floor(this * den) / den;
  },
  "round": function (digits) {
    var den = Math.pow(10, digits == null ? 0 : digits);
    return Math.round(this * den) / den;
  },
  "ceil": function (digits) {
    var den = Math.pow(10, digits == null ? 0 : digits);
    return Math.ceil(this * den) / den;
  },
  "ein": function () {
    var args = [];
    for (var i = 1; i < arguments.length; i++) {
      args.push(arguments[i]);
    }
    return userBinds[arguments[0]].apply(this, args);
  }
};

for (var name in binds) {
  if (Number.prototype[name]) {
    console.warn("`name` already defined in `Number.prototype`");
  }
  else {
    Number.prototype[name] = binds[name];
  }
}

var userBinds = {};

module.exports = function (binds) {
  for (var name in binds) {
    userBinds[name] = binds[name];
  }
};