GoScrobble/web/node_modules/es5-ext/array/#/first-index.js

16 lines
407 B
JavaScript

"use strict";
var toPosInt = require("../../number/to-pos-integer")
, value = require("../../object/valid-value")
, objHasOwnProperty = Object.prototype.hasOwnProperty;
module.exports = function () {
var i, length;
if (!(length = toPosInt(value(this).length))) return null;
i = 0;
while (!objHasOwnProperty.call(this, i)) {
if (++i === length) return null;
}
return i;
};