Is there a way how to globally console.log() all the fired actions in Reflux? Ideally prints theirs parameters at the same time.
Like Cory Danielson said, Reflux uses EventEmitter. And you can insert your own EventEmitter-implementation like this:
Reflux.setEventEmitter(require('events').EventEmitter);
So you want to inject an EventEmitter constructor there that has debugging enabled, something like this:
var EventEmitter = require('events').EventEmitter;
function DebugEventEmitter() {
var realEmitter = new EventEmitter();
var origEmit = realEmitter.emit;
realEmitter.emit = function () {
console.log('emitting', arguments);
return origEmit.apply(realEmitter, arguments);
};
return realEmitter;
}
Reflux.setEventEmitter(DebugEventEmitter);
This only hijacks the emit method which is used to emit events, but you can of course hijack any other method on EventEmitter and add logging.
EDIT
Since Reflux doesn't pass the action name to the emitted event, here's another solution which is way more hackish, but it should work for debugging purposes.
var Reflux = require('reflux');
// Do this before any code is calling Reflux
var origCreateAction = Reflux.createAction;
Reflux.createAction = function () {
var action = origCreateAction.apply(Reflux, arguments);
var wrapper = function () {
console.log(action.actionName, 'called with args: ', arguments);
return action.apply(action, arguments);
};
for (var key in action) {
wrapper[key] = action[key];
}
return wrapper;
};
// Example using actions and triggering them, which logs
// with our wrapper
var Actions = Reflux.createActions([
'statusUpdate',
'statusEdited',
'statusAdded'
]);
Actions.statusUpdate.listen(function () {
console.log('status update called');
});
Actions.statusUpdate({test: 1});
Related
The main reason why I want it is that I want to extend my initialize function.
Something like this:
// main.js
window.onload = init();
function init(){
doSomething();
}
// extend.js
function extends init(){
doSomethingHereToo();
}
So I want to extend a function like I extend a class in PHP.
And I would like to extend it from other files too, so for example I have the original init function in main.js and the extended function in extended.js.
With a wider view of what you're actually trying to do and the context in which you're doing it, I'm sure we could give you a better answer than the literal answer to your question.
But here's a literal answer:
If you're assigning these functions to some property somewhere, you can wrap the original function and put your replacement on the property instead:
// Original code in main.js
var theProperty = init;
function init(){
doSomething();
}
// Extending it by replacing and wrapping, in extended.js
theProperty = (function(old) {
function extendsInit() {
old();
doSomething();
}
return extendsInit;
})(theProperty);
If your functions aren't already on an object, you'd probably want to put them there to facilitate the above. For instance:
// In main.js
var MyLibrary = {
init: function init() {
}
};
// In extended.js
(function() {
var oldInit = MyLibrary.init;
MyLibrary.init = extendedInit;
function extendedInit() {
oldInit.call(MyLibrary); // Use #call in case `init` uses `this`
doSomething();
}
})();
But there are better ways to do that. Like for instance, providing a means of registering init functions.
// In main.js
var MyLibrary = (function() {
var initFunctions = [];
return {
init: function init() {
var fns = initFunctions;
initFunctions = undefined;
for (var index = 0; index < fns.length; ++index) {
try { fns[index](); } catch (e) { }
}
},
addInitFunction: function addInitFunction(fn) {
if (initFunctions) {
// Init hasn't run yet, remember it
initFunctions.push(fn);
} else {
// `init` has already run, call it almost immediately
// but *asynchronously* (so the caller never sees the
// call synchronously)
setTimeout(fn, 0);
}
}
};
})();
Here in 2020 (or really any time after ~2016), that can be written a bit more compactly:
// In main.js
const MyLibrary = (() => {
let initFunctions = [];
return {
init() {
const fns = initFunctions;
initFunctions = undefined;
for (const fn of fns) {
try { fn(); } catch (e) { }
}
},
addInitFunction(fn) {
if (initFunctions) {
// Init hasn't run yet, remember it
initFunctions.push(fn);
} else {
// `init` has already run, call it almost immediately
// but *asynchronously* (so the caller never sees the
// call synchronously)
setTimeout(fn, 0);
// Or: `Promise.resolve().then(() => fn());`
// (Not `.then(fn)` just to avoid passing it an argument)
}
}
};
})();
There are several ways to go about this, it depends what your purpose is, if you just want to execute the function as well and in the same context, you can use .apply():
function init(){
doSomething();
}
function myFunc(){
init.apply(this, arguments);
doSomethingHereToo();
}
If you want to replace it with a newer init, it'd look like this:
function init(){
doSomething();
}
//anytime later
var old_init = init;
init = function() {
old_init.apply(this, arguments);
doSomethingHereToo();
};
The other methods are great but they don't preserve any prototype functions attached to init. To get around that you can do the following (inspired by the post from Nick Craver).
(function () {
var old_prototype = init.prototype;
var old_init = init;
init = function () {
old_init.apply(this, arguments);
// Do something extra
};
init.prototype = old_prototype;
}) ();
Another option could be:
var initial = function() {
console.log( 'initial function!' );
}
var iWantToExecuteThisOneToo = function () {
console.log( 'the other function that i wanted to execute!' );
}
function extendFunction( oldOne, newOne ) {
return (function() {
oldOne();
newOne();
})();
}
var extendedFunction = extendFunction( initial, iWantToExecuteThisOneToo );
2017+ solution
The idea of function extensions comes from functional paradigm, which is natively supported since ES6:
function init(){
doSomething();
}
// extend.js
init = (f => u => { f(u)
doSomethingHereToo();
})(init);
init();
As per #TJCrowder's concern about stack dump, the browsers handle the situation much better today. If you save this code into test.html and run it, you get
test.html:3 Uncaught ReferenceError: doSomething is not defined
at init (test.html:3)
at test.html:8
at test.html:12
Line 12: the init call, Line 8: the init extension, Line 3: the undefined doSomething() call.
Note: Much respect to veteran T.J. Crowder, who kindly answered my question many years ago, when I was a newbie. After the years, I still remember the respectfull attitude and I try to follow the good example.
This is very simple and straight forward. Look at the code. Try to grasp the basic concept behind javascript extension.
First let us extend javascript function.
function Base(props) {
const _props = props
this.getProps = () => _props
// We can make method private by not binding it to this object.
// Hence it is not exposed when we return this.
const privateMethod = () => "do internal stuff"
return this
}
You can extend this function by creating child function in following way
function Child(props) {
const parent = Base(props)
this.getMessage = () => `Message is ${parent.getProps()}`;
// You can remove the line below to extend as in private inheritance,
// not exposing parent function properties and method.
this.prototype = parent
return this
}
Now you can use Child function as follows,
let childObject = Child("Secret Message")
console.log(childObject.getMessage()) // logs "Message is Secret Message"
console.log(childObject.getProps()) // logs "Secret Message"
We can also create Javascript Function by extending Javascript classes, like this.
class BaseClass {
constructor(props) {
this.props = props
// You can remove the line below to make getProps method private.
// As it will not be binded to this, but let it be
this.getProps = this.getProps.bind(this)
}
getProps() {
return this.props
}
}
Let us extend this class with Child function like this,
function Child(props) {
let parent = new BaseClass(props)
const getMessage = () => `Message is ${parent.getProps()}`;
return { ...parent, getMessage} // I have used spread operator.
}
Again you can use Child function as follows to get similar result,
let childObject = Child("Secret Message")
console.log(childObject.getMessage()) // logs "Message is Secret Message"
console.log(childObject.getProps()) // logs "Secret Message"
Javascript is very easy language. We can do almost anything. Happy JavaScripting... Hope I was able to give you an idea to use in your case.
Use extendFunction.js
init = extendFunction(init, function(args) {
doSomethingHereToo();
});
But in your specific case, it's easier to extend the global onload function:
extendFunction('onload', function(args) {
doSomethingHereToo();
});
I actually really like your question, it's making me think about different use cases.
For javascript events, you really want to add and remove handlers - but for extendFunction, how could you later remove functionality? I could easily add a .revert method to extended functions, so init = init.revert() would return the original function. Obviously this could lead to some pretty bad code, but perhaps it lets you get something done without touching a foreign part of the codebase.
I have integrated some HTML/JS Code into my Vaadin WebApplication by creating an AbstractJavaScriptComponent. The Component almost works as intended.
How do I call the passInfo() method defined in the "connector.js" without having to manually click the Button defined in the innerHTML of the "chessControll.JsLabel" Component in "chessControll.js". My Goal is to pass Information, when the onChange Event of the init() function is called, which is located in the same file "chessControll.js", but not part of the Component.
I have already tried to create a Custom Event and then dispatch it whenever onChange() in the init() function is called, it worked as long as I didn't listen for the Event inside of my Component (chessControll.js, chessControll.JsLabel). It seems it can only be accessed in a static way.
How can I access the chessControll.JsLabel in "chessControll.js" from the init() function and then dispatch the button click or listen for events inside the component to achieve the same?
connector.js:
com_*myname*_*applicationName*_JsLabel = function() {
var mycomponent = new chessControll.JsLabel(this.getElement());
connector = this;
this.onStateChange = function() {
mycomponent = this.getState().boolState;
};
mycomponent.click = function() {
connector.passInfo(true);
};
};
chessControll.js:
var chessControll = chessControll || {};
chessControll.JsLabel = function (element) {
element.innerHTML =
"<input type='button' value='Click'/>";
// Getter and setter for the value property
this.getValue = function () {
return element.
getElementsByTagName("input")[0].value;
};
var button = element.getElementsByTagName("input")[0];
var self = this;
button.onclick = function () {
self.click();
};
};
var init = function() {
var onChange = function() {
/*Click Button defined in JsLabel Component */
};
};$(document).ready(init);
I figured out what the problem was.
The architecture of Java Web Applications doesn't allow a simple communication like i did in my example. The JavaScript made a call from the Client Side to the Server Side Vaadin Component.
I integrated the whole JavaScript, including the init function, as a Component. This way i can call the method from the init function because everything is known on the Server Side.
edited chessControll.js :
var chessControll = chessControll || {};
chessControll.JsLabel = function (element) {
element.innerHTML =
"<input type='button' value='Click'/>";
// Getter and setter for the value property
this.getValue = function () {
return element.
getElementsByTagName("input")[0].value;
};
var button = element.getElementsByTagName("input")[0];
var self = this;
//deleted bracket here
var init = function() {
var onChange = function() {
self.click();
};
};$(document).ready(init);
} //<-- that Simple
We are using the Page Object pattern to organize our internal AngularJS application tests.
Here is an example page object we have:
var LoginPage = function () {
this.username = element(by.id("username"));
this.password = element(by.id("password"));
this.loginButton = element(by.id("submit"));
}
module.exports = LoginPage;
In a single-browser test, it is quite clear how to use it:
var LoginPage = require("./../po/login.po.js");
describe("Login functionality", function () {
var scope = {};
beforeEach(function () {
browser.get("/#login");
scope.page = new LoginPage();
});
it("should successfully log in a user", function () {
scope.page.username.clear();
scope.page.username.sendKeys(login);
scope.page.password.sendKeys(password);
scope.page.loginButton.click();
// assert we are logged in
});
});
But, when it comes to a test when multiple browsers are instantiated and there is the need to switch between them in a single test, it is becoming unclear how to use the same page object with multiple browsers:
describe("Login functionality", function () {
var scope = {};
beforeEach(function () {
browser.get("/#login");
scope.page = new LoginPage();
});
it("should warn there is an opened session", function () {
scope.page.username.clear();
scope.page.username.sendKeys(login);
scope.page.password.sendKeys(password);
scope.page.loginButton.click();
// assert we are logged in
// fire up a different browser and log in
var browser2 = browser.forkNewDriverInstance();
// the problem is here - scope.page.username.clear() would be applied to the main "browser"
});
});
Problem:
After we forked a new browser, how can we use the same Page Object fields and functions, but applied to a newly instantiated browser (browser2 in this case)?
In other words, all element() calls here would be applied to browser, but needed to be applied to browser2. How can we switch the context?
Thoughts:
one possible approach here would be to redefine the global element = browser2.element temporarily while being in the context of browser2. The problem with this approach is that we also have browser.wait() calls inside the page object functions. This means that browser = browser2 should be also set. In this case, we would need to remember the browser global object in a temp variable and restore it once we switch back to the main browser context..
another possible approach would be to pass the browser instance into the page object, something like:
var LoginPage = function (browserInstance) {
browser = browserInstance ? browserInstance : browser;
var element = browser.element;
// ...
}
but this would probably require to change every page object we have..
Hope the question is clear - let me know if it needs clarification.
Maybe you could write few functions to make the the browser registration/start/switch smoother. (Basically it is your first option with some support.)
For example:
var browserRegistry = [];
function openNewBrowser(){
if(typeof browserRegistry[0] == 'undefined'){
browseRegistry[0] = {
browser: browser,
element: element,
$: $,
$$: $$,
... whatever else you need.
}
}
var tmp = browser.forkNewDriverInstance();
var id = browserRegistry.length;
browseRegistry[id] = {
browser: tmp,
element: tmp.element,
$: tmp.$,
$$: tmp.$$,
... whatever else you need.
}
switchToBrowserContext(id);
return id;
}
function switchToBrowserContext(id){
browser=browseRegistry[id].browser;
element=browseRegistry[id].element;
$=browseRegistry[id].$;
$$=browseRegistry[id].$$;
}
And you use it this way in your example:
describe("Login functionality", function () {
var scope = {};
beforeEach(function () {
browser.get("/#login");
scope.page1 = new LoginPage();
openNewBrowser();
browser.get("/#login");
scope.page2 = new LoginPage();
});
it("should warn there is an opened session", function () {
scope.page1.username.clear();
scope.page1.username.sendKeys(login);
scope.page1.password.sendKeys(password);
scope.page1.loginButton.click();
scope.page2.username.clear();
scope.page2.username.sendKeys(login);
scope.page2.password.sendKeys(password);
scope.page2.loginButton.click();
});
});
So you can leave your page objects as they are.
To be honest I think your second approach is cleaner...
Using global variables can bite back later.
But if you don't want to change your POs, this can also work.
(I did not test it... sorry for the likely typos/errors.)
(You can place the support functions to your protractor conf's onprepare section for example.)
Look at my solution. I simplified example, but we are using this approach in current project. My app has pages for both user permissions types, and i need to do some complex actions same time in both browsers. I hope this might show you some new, better way!
"use strict";
//In config, you should declare global browser roles. I only have 2 roles - so i make 2 global instances
//Somewhere in onPrepare() function
global.admin = browser;
admin.admin = true;
global.guest = browser.forkNewDriverInstance();
guest.guest = true;
//Notice that default browser will be 'admin' example:
// let someElement = $('someElement'); // this will be tried to be found in admin browser.
class BasePage {
//Other shared logic also can be added here.
constructor (browser = admin) {
//Simplified example
this._browser = browser
}
}
class HomePage extends BasePage {
//You will not directly create this object. Instead you should use .getPageFor(browser)
constructor(browser) {
super(browser);
this.rightToolbar = ToolbarFragment.getFragmentFor(this._browser);
this.chat = ChatFragment.getFragmentFor(this._browser);
this.someOtherNiceButton = this._browser.$('button.menu');
}
//This function relies on params that we have patched for browser instances in onPrepare();
static getPageFor(browser) {
if (browser.guest) return new GuestHomePage(browser);
else if (browser.admin) return new AdminHomePage(browser);
}
openProfileMenu() {
let menu = ProfileMenuFragment.getFragmentFor(this._browser);
this.someOtherNiceButton.click();
return menu;
}
}
class GuestHomePage extends RoomPage {
constructor(browser) {
super(browser);
}
//Some feature that is only available for guest
login() {
// will be 'guest' browser in this case.
this._browser.$('input.login').sendKeys('sdkfj'); //blabla
this._browser.$('input.pass').sendKeys('2345'); //blabla
this._browser.$('button.login').click();
}
}
class AdminHomePage extends RoomPage {
constructor(browser) {
super(browser);
}
acceptGuest() {
let acceptGuestButton = this._browser.$('.request-admission .control-btn.admit-user');
this._browser.wait(EC.elementToBeClickable(acceptGuestButton), 10000,
'Admin should be able to see and click accept guest button. ' +
'Make sure that guest is currently trying to connect to the page');
acceptGuestButton.click();
//Calling browser directly since we need to do complex action. Just example.
guest.wait(EC.visibilityOf(guest.$('.central-content')), 10000, 'Guest should be dropped to the page');
}
}
//Then in your tests
let guestHomePage = HomePage.getPageFor(guest);
guestHomePage.login();
let adminHomePage = HomePage.getPageFor(admin);
adminHomePage.acceptGuest();
adminHomePage.openProfileMenu();
guestHomePage.openProfileMenu();
I'd like to be able to use a public method for a callback instead of passing it as an argument
as in
function Car() {
var that = this;
this.onGearChanged = function(callback) {
callback();
};
setTimeout(that.onGearChanged, 2000);
}
var car = new Car();
car.onGearChanged(function(){
console.log("gear changed");
});
instead of
var onGearChanged = function(){
console.log("gear changed")
}
var car = new Car(arg, arg, onGearChange);
how would I go about it? Should i follow an observer pattern?
I think you need something like this:
function Event(sender) {
this._sender = sender;
this._listeners = [];
}
Event.prototype = {
attach: function (listener) {
this._listeners.push(listener);
},
notify: function (args) {
for (var i = 0; i < this._listeners.length; i++) {
this._listeners[i](this._sender, args);
}
}
};
You Car class:
function Car(gear) {
var self = this;
self.Gear = gear;
self.GearChanged = new Event(this);
//Example method to trigger your GearChanged event. In your real code, you may have different logic
self.changeGear = function (newGear){
self.Gear = newGear;
//notify all subscribers
self.GearChanged.notify(newGear);
}
}
Example code to subscribe to events:
var car = new Car("gear");
car.GearChanged.attach(function (sender,args){
console.log("gear changed");
console.log("new gear value is:" + args);
});
//do some logic that may trigger gearChanged event.
car.changeGear("new Gear");
You can attach more event handlers and all these event handlers will get called. And you can also add more events like: tireChanged,.. easily with this structure.
The code will be more or less complex, depending on your requirements that are not clear. Don't use a pattern if you don't need it, and a pattern can be adjusted in many ways depending on your requirements. Don't try to build the all-for-all solution if you don't realy need it.
If you have many observers and know them at creation time of the car, you can use
function Car(onGearChangedArray) {
this.triggerGearChanged = function() {
for (var i=0;i<onGearChangedArray.length;i++) {
onGearChangedArray[i]();
}
};
window.setTimeout(this.triggerGearChanged,2000);
}
var car = new Car([function(){
console.log("gear changed");
}]);
If you only have exactly one observer, you can get rid of the for loop.
But if you need the flexibility to add them at runtime:
function Car() {
var onGearChangedCallbacks = [];
this.onGearChanged = function(callback) {
onGearChangedCallbacks.push(callback);
};
this.triggerGearChanged = function() {
for (var i=0;i<onGearChangedCallbacks.length;i++) {
onGearChangedCallbacks[i]();
}
};
window.setTimeout(this.triggerGearChanged,2000);
}
var car = new Car();
car.onGearChanged(function(){
console.log("gear changed");
});
Or if you want to abstract it the next level
function Event() {
var callbacks = [];
this.bind = function(callback) {
callbacks.push(callback);
};
this.fire = function() {
for (var i=0;i<callbacks.length;i++) {
callbacks[i]();
}
};
}
function Car() {
this.gearChanged = new Event();
window.setTimeout(this.gearChanged.fire,2000);
}
var car = new Car();
car.gearChanged.bind(function(){
console.log("gear changed");
});
Thanks for the abstraction idea to Khanh TO, I just wanted to show it without parameters.
You could also consider using something more sophisticated, so that you don't need to write this event handling code yourself (like error handling etc.), but again, it depends on your needs. Do you need a fail fast strategy, or should errors be just logged? Must Listeners be unregistered? Could you trap yourself in an infinite loop because triggerGearChanged could lead to another triggerGearChanged? Do you need to pass parameters or not? Keep in mind to keep it as simple as possible, so if you don't need to pass parameters, then don't do it.
If you like unserscore.js, a good start may be http://mattmueller.me/blog/underscore-extension-observer-pattern
The main reason why I want it is that I want to extend my initialize function.
Something like this:
// main.js
window.onload = init();
function init(){
doSomething();
}
// extend.js
function extends init(){
doSomethingHereToo();
}
So I want to extend a function like I extend a class in PHP.
And I would like to extend it from other files too, so for example I have the original init function in main.js and the extended function in extended.js.
With a wider view of what you're actually trying to do and the context in which you're doing it, I'm sure we could give you a better answer than the literal answer to your question.
But here's a literal answer:
If you're assigning these functions to some property somewhere, you can wrap the original function and put your replacement on the property instead:
// Original code in main.js
var theProperty = init;
function init(){
doSomething();
}
// Extending it by replacing and wrapping, in extended.js
theProperty = (function(old) {
function extendsInit() {
old();
doSomething();
}
return extendsInit;
})(theProperty);
If your functions aren't already on an object, you'd probably want to put them there to facilitate the above. For instance:
// In main.js
var MyLibrary = {
init: function init() {
}
};
// In extended.js
(function() {
var oldInit = MyLibrary.init;
MyLibrary.init = extendedInit;
function extendedInit() {
oldInit.call(MyLibrary); // Use #call in case `init` uses `this`
doSomething();
}
})();
But there are better ways to do that. Like for instance, providing a means of registering init functions.
// In main.js
var MyLibrary = (function() {
var initFunctions = [];
return {
init: function init() {
var fns = initFunctions;
initFunctions = undefined;
for (var index = 0; index < fns.length; ++index) {
try { fns[index](); } catch (e) { }
}
},
addInitFunction: function addInitFunction(fn) {
if (initFunctions) {
// Init hasn't run yet, remember it
initFunctions.push(fn);
} else {
// `init` has already run, call it almost immediately
// but *asynchronously* (so the caller never sees the
// call synchronously)
setTimeout(fn, 0);
}
}
};
})();
Here in 2020 (or really any time after ~2016), that can be written a bit more compactly:
// In main.js
const MyLibrary = (() => {
let initFunctions = [];
return {
init() {
const fns = initFunctions;
initFunctions = undefined;
for (const fn of fns) {
try { fn(); } catch (e) { }
}
},
addInitFunction(fn) {
if (initFunctions) {
// Init hasn't run yet, remember it
initFunctions.push(fn);
} else {
// `init` has already run, call it almost immediately
// but *asynchronously* (so the caller never sees the
// call synchronously)
setTimeout(fn, 0);
// Or: `Promise.resolve().then(() => fn());`
// (Not `.then(fn)` just to avoid passing it an argument)
}
}
};
})();
There are several ways to go about this, it depends what your purpose is, if you just want to execute the function as well and in the same context, you can use .apply():
function init(){
doSomething();
}
function myFunc(){
init.apply(this, arguments);
doSomethingHereToo();
}
If you want to replace it with a newer init, it'd look like this:
function init(){
doSomething();
}
//anytime later
var old_init = init;
init = function() {
old_init.apply(this, arguments);
doSomethingHereToo();
};
The other methods are great but they don't preserve any prototype functions attached to init. To get around that you can do the following (inspired by the post from Nick Craver).
(function () {
var old_prototype = init.prototype;
var old_init = init;
init = function () {
old_init.apply(this, arguments);
// Do something extra
};
init.prototype = old_prototype;
}) ();
Another option could be:
var initial = function() {
console.log( 'initial function!' );
}
var iWantToExecuteThisOneToo = function () {
console.log( 'the other function that i wanted to execute!' );
}
function extendFunction( oldOne, newOne ) {
return (function() {
oldOne();
newOne();
})();
}
var extendedFunction = extendFunction( initial, iWantToExecuteThisOneToo );
2017+ solution
The idea of function extensions comes from functional paradigm, which is natively supported since ES6:
function init(){
doSomething();
}
// extend.js
init = (f => u => { f(u)
doSomethingHereToo();
})(init);
init();
As per #TJCrowder's concern about stack dump, the browsers handle the situation much better today. If you save this code into test.html and run it, you get
test.html:3 Uncaught ReferenceError: doSomething is not defined
at init (test.html:3)
at test.html:8
at test.html:12
Line 12: the init call, Line 8: the init extension, Line 3: the undefined doSomething() call.
Note: Much respect to veteran T.J. Crowder, who kindly answered my question many years ago, when I was a newbie. After the years, I still remember the respectfull attitude and I try to follow the good example.
This is very simple and straight forward. Look at the code. Try to grasp the basic concept behind javascript extension.
First let us extend javascript function.
function Base(props) {
const _props = props
this.getProps = () => _props
// We can make method private by not binding it to this object.
// Hence it is not exposed when we return this.
const privateMethod = () => "do internal stuff"
return this
}
You can extend this function by creating child function in following way
function Child(props) {
const parent = Base(props)
this.getMessage = () => `Message is ${parent.getProps()}`;
// You can remove the line below to extend as in private inheritance,
// not exposing parent function properties and method.
this.prototype = parent
return this
}
Now you can use Child function as follows,
let childObject = Child("Secret Message")
console.log(childObject.getMessage()) // logs "Message is Secret Message"
console.log(childObject.getProps()) // logs "Secret Message"
We can also create Javascript Function by extending Javascript classes, like this.
class BaseClass {
constructor(props) {
this.props = props
// You can remove the line below to make getProps method private.
// As it will not be binded to this, but let it be
this.getProps = this.getProps.bind(this)
}
getProps() {
return this.props
}
}
Let us extend this class with Child function like this,
function Child(props) {
let parent = new BaseClass(props)
const getMessage = () => `Message is ${parent.getProps()}`;
return { ...parent, getMessage} // I have used spread operator.
}
Again you can use Child function as follows to get similar result,
let childObject = Child("Secret Message")
console.log(childObject.getMessage()) // logs "Message is Secret Message"
console.log(childObject.getProps()) // logs "Secret Message"
Javascript is very easy language. We can do almost anything. Happy JavaScripting... Hope I was able to give you an idea to use in your case.
as I understand it, you are trying to fetch the applications connected to the user account. You can do this by making a request on the API, I don't know if discord.js covers this part of the API
endpoint: https://discord.com/api/users/#me/connections
Request type: GET Header:
Authorization: "Beareryou token"
response: [
{...}
]
Use extendFunction.js
init = extendFunction(init, function(args) {
doSomethingHereToo();
});
But in your specific case, it's easier to extend the global onload function:
extendFunction('onload', function(args) {
doSomethingHereToo();
});
I actually really like your question, it's making me think about different use cases.
For javascript events, you really want to add and remove handlers - but for extendFunction, how could you later remove functionality? I could easily add a .revert method to extended functions, so init = init.revert() would return the original function. Obviously this could lead to some pretty bad code, but perhaps it lets you get something done without touching a foreign part of the codebase.