16 lines
407 B
JavaScript
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;
|
|
};
|