esnext.map.map-values.js 1.2 KB

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  1. 'use strict';
  2. var IS_PURE = require('../internals/is-pure');
  3. var $ = require('../internals/export');
  4. var getBuiltIn = require('../internals/get-built-in');
  5. var bind = require('../internals/function-bind-context');
  6. var call = require('../internals/function-call');
  7. var aCallable = require('../internals/a-callable');
  8. var anObject = require('../internals/an-object');
  9. var speciesConstructor = require('../internals/species-constructor');
  10. var getMapIterator = require('../internals/get-map-iterator');
  11. var iterate = require('../internals/iterate');
  12. // `Map.prototype.mapValues` method
  13. // https://github.com/tc39/proposal-collection-methods
  14. $({ target: 'Map', proto: true, real: true, forced: IS_PURE }, {
  15. mapValues: function mapValues(callbackfn /* , thisArg */) {
  16. var map = anObject(this);
  17. var iterator = getMapIterator(map);
  18. var boundFunction = bind(callbackfn, arguments.length > 1 ? arguments[1] : undefined);
  19. var newMap = new (speciesConstructor(map, getBuiltIn('Map')))();
  20. var setter = aCallable(newMap.set);
  21. iterate(iterator, function (key, value) {
  22. call(setter, newMap, key, boundFunction(value, key, map));
  23. }, { AS_ENTRIES: true, IS_ITERATOR: true });
  24. return newMap;
  25. }
  26. });