20 lines
854 B
JavaScript
20 lines
854 B
JavaScript
'use strict';
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var $ = require('../internals/export');
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var IS_PURE = require('../internals/is-pure');
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var anObject = require('../internals/an-object');
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var bind = require('../internals/bind-context');
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var getMapIterator = require('../internals/get-map-iterator');
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var iterate = require('../internals/iterate');
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// `Map.prototype.findKey` method
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// https://github.com/tc39/proposal-collection-methods
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$({ target: 'Map', proto: true, real: true, forced: IS_PURE }, {
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findKey: function findKey(callbackfn /* , thisArg */) {
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var map = anObject(this);
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var iterator = getMapIterator(map);
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var boundFunction = bind(callbackfn, arguments.length > 1 ? arguments[1] : undefined, 3);
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return iterate(iterator, function (key, value) {
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if (boundFunction(value, key, map)) return iterate.stop(key);
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}, undefined, true, true).result;
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}
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});
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