18 lines
644 B
JavaScript
18 lines
644 B
JavaScript
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'use strict';
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var $TypeError = require('es-errors/type');
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var isInteger = require('../helpers/isInteger');
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var callBound = require('call-bind/callBound');
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var $slice = callBound('String.prototype.slice');
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// https://262.ecma-international.org/12.0/#substring
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module.exports = function substring(S, inclusiveStart, exclusiveEnd) {
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if (typeof S !== 'string' || !isInteger(inclusiveStart) || (arguments.length > 2 && !isInteger(exclusiveEnd))) {
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throw new $TypeError('`S` must be a String, and `inclusiveStart` and `exclusiveEnd` must be integers');
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}
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return $slice(S, inclusiveStart, arguments.length > 2 ? exclusiveEnd : S.length);
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};
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