21 lines
743 B
JavaScript
Executable file
21 lines
743 B
JavaScript
Executable file
'use strict';
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var $ = require('../internals/export');
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var toObject = require('../internals/to-object');
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var lengthOfArrayLike = require('../internals/length-of-array-like');
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var toIntegerOrInfinity = require('../internals/to-integer-or-infinity');
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var addToUnscopables = require('../internals/add-to-unscopables');
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// `Array.prototype.at` method
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// https://github.com/tc39/proposal-relative-indexing-method
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$({ target: 'Array', proto: true }, {
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at: function at(index) {
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var O = toObject(this);
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var len = lengthOfArrayLike(O);
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var relativeIndex = toIntegerOrInfinity(index);
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var k = relativeIndex >= 0 ? relativeIndex : len + relativeIndex;
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return (k < 0 || k >= len) ? undefined : O[k];
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}
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});
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addToUnscopables('at');
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