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- // 21.1.3.18 String.prototype.startsWith(searchString [, position ])
- 'use strict';
- var $export = require('./_export');
- var toLength = require('./_to-length');
- var context = require('./_string-context');
- var STARTS_WITH = 'startsWith';
- var $startsWith = ''[STARTS_WITH];
- $export($export.P + $export.F * require('./_fails-is-regexp')(STARTS_WITH), 'String', {
- startsWith: function startsWith(searchString /* , position = 0 */) {
- var that = context(this, searchString, STARTS_WITH);
- var index = toLength(Math.min(arguments.length > 1 ? arguments[1] : undefined, that.length));
- var search = String(searchString);
- return $startsWith
- ? $startsWith.call(that, search, index)
- : that.slice(index, index + search.length) === search;
- }
- });
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