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How to subclass a promise
// ES6
class AngularPromise extends Promise {
constructor(executor) {
super((resolve, reject) => {
// before
return executor(resolve, reject);
});
// after
}
then(onFulfilled, onRejected) {
// before
const returnValue = super.then(onFulfilled, onRejected);
// after
return returnValue;
}
}
// ES5
function AngularPromise(executor) {
var p = new Promise(function (resolve, reject) {
// before
return executor(resolve, reject);
});
// after
p.__proto__ = AngularPromise.prototype;
return p;
}
AngularPromise.__proto__ = Promise;
AngularPromise.prototype.__proto__ = Promise.prototype;
AngularPromise.prototype.then = function then(onFulfilled, onRejected) {
// before
var returnValue = Promise.prototype.then.call(this, onFulfilled, onRejected);
// after
return returnValue;
}
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