'use strict'; var define = require('define-properties'); var shimUnscopables = require('es-shim-unscopables'); var getPolyfill = require('./polyfill'); module.exports = function shimFlatMap() { var polyfill = getPolyfill(); define( Array.prototype, { flatMap: polyfill }, { flatMap: function () { return Array.prototype.flatMap !== polyfill; } } ); shimUnscopables('flatMap'); return polyfill; };