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