1"use strict";
2
3exports.__esModule = true;
4
5var _symbol = require("../core-js/symbol");
6
7var _symbol2 = _interopRequireDefault(_symbol);
8
9var _promise = require("../core-js/promise");
10
11var _promise2 = _interopRequireDefault(_promise);
12
13function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
14
15exports.default = function () {
16  function AwaitValue(value) {
17    this.value = value;
18  }
19
20  function AsyncGenerator(gen) {
21    var front, back;
22
23    function send(key, arg) {
24      return new _promise2.default(function (resolve, reject) {
25        var request = {
26          key: key,
27          arg: arg,
28          resolve: resolve,
29          reject: reject,
30          next: null
31        };
32
33        if (back) {
34          back = back.next = request;
35        } else {
36          front = back = request;
37          resume(key, arg);
38        }
39      });
40    }
41
42    function resume(key, arg) {
43      try {
44        var result = gen[key](arg);
45        var value = result.value;
46
47        if (value instanceof AwaitValue) {
48          _promise2.default.resolve(value.value).then(function (arg) {
49            resume("next", arg);
50          }, function (arg) {
51            resume("throw", arg);
52          });
53        } else {
54          settle(result.done ? "return" : "normal", result.value);
55        }
56      } catch (err) {
57        settle("throw", err);
58      }
59    }
60
61    function settle(type, value) {
62      switch (type) {
63        case "return":
64          front.resolve({
65            value: value,
66            done: true
67          });
68          break;
69
70        case "throw":
71          front.reject(value);
72          break;
73
74        default:
75          front.resolve({
76            value: value,
77            done: false
78          });
79          break;
80      }
81
82      front = front.next;
83
84      if (front) {
85        resume(front.key, front.arg);
86      } else {
87        back = null;
88      }
89    }
90
91    this._invoke = send;
92
93    if (typeof gen.return !== "function") {
94      this.return = undefined;
95    }
96  }
97
98  if (typeof _symbol2.default === "function" && _symbol2.default.asyncIterator) {
99    AsyncGenerator.prototype[_symbol2.default.asyncIterator] = function () {
100      return this;
101    };
102  }
103
104  AsyncGenerator.prototype.next = function (arg) {
105    return this._invoke("next", arg);
106  };
107
108  AsyncGenerator.prototype.throw = function (arg) {
109    return this._invoke("throw", arg);
110  };
111
112  AsyncGenerator.prototype.return = function (arg) {
113    return this._invoke("return", arg);
114  };
115
116  return {
117    wrap: function wrap(fn) {
118      return function () {
119        return new AsyncGenerator(fn.apply(this, arguments));
120      };
121    },
122    await: function _await(value) {
123      return new AwaitValue(value);
124    }
125  };
126}();