mirror of
https://github.com/idanoo/GoScrobble.git
synced 2024-11-25 09:55:15 +00:00
95 lines
2.0 KiB
JavaScript
95 lines
2.0 KiB
JavaScript
|
import AwaitValue from "./AwaitValue.js";
|
||
|
export default function AsyncGenerator(gen) {
|
||
|
var front, back;
|
||
|
|
||
|
function send(key, arg) {
|
||
|
return new Promise(function (resolve, reject) {
|
||
|
var request = {
|
||
|
key: key,
|
||
|
arg: arg,
|
||
|
resolve: resolve,
|
||
|
reject: reject,
|
||
|
next: null
|
||
|
};
|
||
|
|
||
|
if (back) {
|
||
|
back = back.next = request;
|
||
|
} else {
|
||
|
front = back = request;
|
||
|
resume(key, arg);
|
||
|
}
|
||
|
});
|
||
|
}
|
||
|
|
||
|
function resume(key, arg) {
|
||
|
try {
|
||
|
var result = gen[key](arg);
|
||
|
var value = result.value;
|
||
|
var wrappedAwait = value instanceof AwaitValue;
|
||
|
Promise.resolve(wrappedAwait ? value.wrapped : value).then(function (arg) {
|
||
|
if (wrappedAwait) {
|
||
|
resume(key === "return" ? "return" : "next", arg);
|
||
|
return;
|
||
|
}
|
||
|
|
||
|
settle(result.done ? "return" : "normal", arg);
|
||
|
}, function (err) {
|
||
|
resume("throw", err);
|
||
|
});
|
||
|
} catch (err) {
|
||
|
settle("throw", err);
|
||
|
}
|
||
|
}
|
||
|
|
||
|
function settle(type, value) {
|
||
|
switch (type) {
|
||
|
case "return":
|
||
|
front.resolve({
|
||
|
value: value,
|
||
|
done: true
|
||
|
});
|
||
|
break;
|
||
|
|
||
|
case "throw":
|
||
|
front.reject(value);
|
||
|
break;
|
||
|
|
||
|
default:
|
||
|
front.resolve({
|
||
|
value: value,
|
||
|
done: false
|
||
|
});
|
||
|
break;
|
||
|
}
|
||
|
|
||
|
front = front.next;
|
||
|
|
||
|
if (front) {
|
||
|
resume(front.key, front.arg);
|
||
|
} else {
|
||
|
back = null;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
this._invoke = send;
|
||
|
|
||
|
if (typeof gen["return"] !== "function") {
|
||
|
this["return"] = undefined;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
AsyncGenerator.prototype[typeof Symbol === "function" && Symbol.asyncIterator || "@@asyncIterator"] = function () {
|
||
|
return this;
|
||
|
};
|
||
|
|
||
|
AsyncGenerator.prototype.next = function (arg) {
|
||
|
return this._invoke("next", arg);
|
||
|
};
|
||
|
|
||
|
AsyncGenerator.prototype["throw"] = function (arg) {
|
||
|
return this._invoke("throw", arg);
|
||
|
};
|
||
|
|
||
|
AsyncGenerator.prototype["return"] = function (arg) {
|
||
|
return this._invoke("return", arg);
|
||
|
};
|