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'use strict';
var _createClass = (function () { function defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ('value' in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } } return function (Constructor, protoProps, staticProps) { if (protoProps) defineProperties(Constructor.prototype, protoProps); if (staticProps) defineProperties(Constructor, staticProps); return Constructor; }; })();
function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError('Cannot call a class as a function'); } }
var Promise = (function () {
function Promise(fn) {
_classCallCheck(this, Promise);
this.state = 'pending';
this.value = null;
this.deferreds = [];
this.resolve = this.resolve.bind(this);
this.reject = this.reject.bind(this);
fn(this.resolve, this.reject);
}
_createClass(Promise, [{
key: 'handle',
value: function handle(deferred) {
if (this.state === 'pending') {
this.deferreds.push(deferred);
return;
}
var cb = this.state === 'fulfilled' ? deferred.onFulfilled : deferred.onRejected,
ret;
if (cb === null) {
cb = this.state === 'fulfilled' ? deferred.resolve : deferred.reject;
cb(this.value);
return;
}
try {
ret = cb(this.value);
deferred.resolve(ret);
} catch (e) {
deferred.reject(e);
}
}
}, {
key: 'resolve',
value: function resolve(newValue) {
if (newValue && (typeof newValue === 'object' || typeof newValue === 'function')) {
var then = newValue.then;
if (typeof then === 'function') {
then.call(newValue, this.resolve, this.reject);
return;
}
}
this.state = 'fulfilled';
this.value = newValue;
this.finale();
}
}, {
key: 'reject',
value: function reject(reason) {
this.state = 'rejected';
this.value = reason;
this.finale();
}
}, {
key: 'finale',
value: function finale() {
setTimeout((function () {
console.log(this);
this.deferreds.forEach((function (deferred) {
this.handle(deferred);
}).bind(this));
}).bind(this), 0);
}
}, {
key: 'then',
value: function then(onFulfilled, onRejected) {
return new Promise((function (resolve, reject) {
this.handle({
onFulfilled: onFulfilled || null,
onRejected: onRejected || null,
resolve: resolve,
reject: reject
});
}).bind(this));
}
}]);
return Promise;
})();
var a = new Promise(function (res, rej) {
setTimeout(function () {
var a = 1;
var b = 2;
if (1) {
res(a);
} else {
rej(b);
}
}, 2000);
});
var b = new Promise(function (res, rej) {
setTimeout(function () {
var c = 3;
var d = 4;
if (1) {
res(c);
} else {
rej(d);
}
}, 2000);
});
a.then(function (y) {
return console.log(y);
}, function (n) {
return console.log(n);
}).then(function () {
return b;
}).then(function (y) {
return console.log(y);
});
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