2 var call = require('../internals/function-call');
3 var aCallable = require('../internals/a-callable');
4 var anObject = require('../internals/an-object');
5 var create = require('../internals/object-create');
6 var createNonEnumerableProperty = require('../internals/create-non-enumerable-property');
7 var redefineAll = require('../internals/redefine-all');
8 var wellKnownSymbol = require('../internals/well-known-symbol');
9 var InternalStateModule = require('../internals/internal-state');
10 var getMethod = require('../internals/get-method');
11 var IteratorPrototype = require('../internals/iterators-core').IteratorPrototype;
13 var setInternalState = InternalStateModule.set;
14 var getInternalState = InternalStateModule.get;
16 var TO_STRING_TAG = wellKnownSymbol('toStringTag');
18 module.exports = function (nextHandler, IS_ITERATOR) {
19 var IteratorProxy = function Iterator(state) {
20 state.next = aCallable(state.iterator.next);
22 state.ignoreArg = !IS_ITERATOR;
23 setInternalState(this, state);
26 IteratorProxy.prototype = redefineAll(create(IteratorPrototype), {
27 next: function next(arg) {
28 var state = getInternalState(this);
29 var args = arguments.length ? [state.ignoreArg ? undefined : arg] : IS_ITERATOR ? [] : [undefined];
30 state.ignoreArg = false;
31 var result = state.done ? undefined : call(nextHandler, state, args);
32 return { done: state.done, value: result };
34 'return': function (value) {
35 var state = getInternalState(this);
36 var iterator = state.iterator;
38 var $$return = getMethod(iterator, 'return');
39 return { done: true, value: $$return ? anObject(call($$return, iterator, value)).value : value };
41 'throw': function (value) {
42 var state = getInternalState(this);
43 var iterator = state.iterator;
45 var $$throw = getMethod(iterator, 'throw');
46 if ($$throw) return call($$throw, iterator, value);
52 createNonEnumerableProperty(IteratorProxy.prototype, TO_STRING_TAG, 'Generator');