2016-10-10 03:43:44 +02:00
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// 21.1.3.18 String.prototype.startsWith(searchString [, position ])
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'use strict';
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2017-04-20 03:09:25 +02:00
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var $export = require('./$.export')
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, toLength = require('./$.to-length')
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, context = require('./$.string-context')
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2016-10-10 03:43:44 +02:00
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, STARTS_WITH = 'startsWith'
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, $startsWith = ''[STARTS_WITH];
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2017-04-20 03:09:25 +02:00
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$export($export.P + $export.F * require('./$.fails-is-regexp')(STARTS_WITH), 'String', {
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2016-10-10 03:43:44 +02:00
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startsWith: function startsWith(searchString /*, position = 0 */){
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var that = context(this, searchString, STARTS_WITH)
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2017-04-20 03:09:25 +02:00
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, $$ = arguments
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, index = toLength(Math.min($$.length > 1 ? $$[1] : undefined, that.length))
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2016-10-10 03:43:44 +02:00
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, search = String(searchString);
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return $startsWith
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? $startsWith.call(that, search, index)
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: that.slice(index, index + search.length) === search;
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}
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});
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