.config/coc/extensions/node_modules/coc-prettier/node_modules/core-js/modules/esnext.map.group-by.js

   1 'use strict';
   2 var $ = require('../internals/export');
   3 var iterate = require('../internals/iterate');
   4 var aFunction = require('../internals/a-function');
   5
   6 // `Map.groupBy` method
   7 // https://github.com/tc39/proposal-collection-methods
   8 $({ target: 'Map', stat: true }, {
   9   groupBy: function groupBy(iterable, keyDerivative) {
  10     var newMap = new this();
  11     aFunction(keyDerivative);
  12     var has = aFunction(newMap.has);
  13     var get = aFunction(newMap.get);
  14     var set = aFunction(newMap.set);
  15     iterate(iterable, function (element) {
  16       var derivedKey = keyDerivative(element);
  17       if (!has.call(newMap, derivedKey)) set.call(newMap, derivedKey, [element]);
  18       else get.call(newMap, derivedKey).push(element);
  19     });
  20     return newMap;
  21   }
  22 });