23 lines
815 B
JavaScript
23 lines
815 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 aFunction = require('../internals/a-function');
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// `Set.prototype.update` 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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update: function update(key, callback /* , thunk */) {
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var map = anObject(this);
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var length = arguments.length;
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aFunction(callback);
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var isPresentInMap = map.has(key);
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if (!isPresentInMap && length < 3) {
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throw TypeError('Updating absent value');
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}
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var value = isPresentInMap ? map.get(key) : aFunction(length > 2 ? arguments[2] : undefined)(key, map);
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map.set(key, callback(value, key, map));
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return map;
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}
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});
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