mirror of https://github.com/jkjoy/sunpeiwen.git
27 lines
686 B
JavaScript
27 lines
686 B
JavaScript
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'use strict';
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var GetIntrinsic = require('get-intrinsic');
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var $RangeError = GetIntrinsic('%RangeError%');
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var ToIntegerOrInfinity = require('./ToIntegerOrInfinity');
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var ToLength = require('./ToLength');
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var SameValue = require('./SameValue');
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// https://262.ecma-international.org/8.0/#sec-toindex
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module.exports = function ToIndex(value) {
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if (typeof value === 'undefined') {
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return 0;
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}
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var integerIndex = ToIntegerOrInfinity(value);
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if (integerIndex < 0) {
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throw new $RangeError('index must be >= 0');
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}
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var index = ToLength(integerIndex);
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if (!SameValue(integerIndex, index)) {
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throw new $RangeError('index must be >= 0 and < 2 ** 53 - 1');
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}
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return index;
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};
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