core-js/internals/get-iterator-internal.js

Standard library

'use strict';
var call = require('../internals/function-call');
var isCallable = require('../internals/is-callable');
var anObject = require('../internals/an-object');
var tryToString = require('../internals/try-to-string');
var getIteratorMethod = require('../internals/get-iterator-method-internal');

var $TypeError = TypeError;

module.exports = function (argument, usingIterator) {
  var iteratorMethod = arguments.length < 2 ? getIteratorMethod(argument) : usingIterator;
  if (isCallable(iteratorMethod)) return anObject(call(iteratorMethod, argument));
  throw new $TypeError(tryToString(argument) + ' is not iterable');
};