[79a0317] | 1 | 'use strict';
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| 2 | var $ = require('../internals/export');
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| 3 | var uncurryThis = require('../internals/function-uncurry-this-clause');
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| 4 | var getOwnPropertyDescriptor = require('../internals/object-get-own-property-descriptor').f;
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| 5 | var toLength = require('../internals/to-length');
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| 6 | var toString = require('../internals/to-string');
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| 7 | var notARegExp = require('../internals/not-a-regexp');
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| 8 | var requireObjectCoercible = require('../internals/require-object-coercible');
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| 9 | var correctIsRegExpLogic = require('../internals/correct-is-regexp-logic');
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| 10 | var IS_PURE = require('../internals/is-pure');
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| 11 |
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| 12 | var stringSlice = uncurryThis(''.slice);
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| 13 | var min = Math.min;
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| 14 |
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| 15 | var CORRECT_IS_REGEXP_LOGIC = correctIsRegExpLogic('startsWith');
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| 16 | // https://github.com/zloirock/core-js/pull/702
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| 17 | var MDN_POLYFILL_BUG = !IS_PURE && !CORRECT_IS_REGEXP_LOGIC && !!function () {
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| 18 | var descriptor = getOwnPropertyDescriptor(String.prototype, 'startsWith');
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| 19 | return descriptor && !descriptor.writable;
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| 20 | }();
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| 21 |
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| 22 | // `String.prototype.startsWith` method
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| 23 | // https://tc39.es/ecma262/#sec-string.prototype.startswith
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| 24 | $({ target: 'String', proto: true, forced: !MDN_POLYFILL_BUG && !CORRECT_IS_REGEXP_LOGIC }, {
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| 25 | startsWith: function startsWith(searchString /* , position = 0 */) {
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| 26 | var that = toString(requireObjectCoercible(this));
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| 27 | notARegExp(searchString);
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| 28 | var index = toLength(min(arguments.length > 1 ? arguments[1] : undefined, that.length));
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| 29 | var search = toString(searchString);
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| 30 | return stringSlice(that, index, index + search.length) === search;
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| 31 | }
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| 32 | });
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