That's the thing i was going to mention with arrow functions you also don't need to use bind since the arrow functions keep the scope open to the father scope
Nearly 3 years before I saw his video related to Angular Testing. I was so impressed, I liked his teaching very much. I became his fan. After 3 years, today I found this video of him. Sorry sir, but this comment's targeted to you. You please speak with your slang sir, don't try to create new slang.
Very helpful. Thanks. I think instead of using call/apply, better & shorter now to use es6 spread operator, to copy functionality from obj to obj. Commonly used in react now. Example: function doSomething (x,y,z){ } let args = [a,b,c] doSomething(...args)
To turn the argument into an array, we could also do make the argument a spread operator when passing it into the function then convert it into an array by saying: Let arrArgs; Let argsToArray= function(){ return arrArgs=[...arguments]; }; Right? And then calling the function argsToArray(1,2,3) should console[1,2,3]?
With New ES 6 feature, to find out the Minimum value from array use REST operator let myarr= [1,2,3]; console.log(Math.min(...myarr)); Its just FYI for all
This is better than any paid tutorial I have gone through. Thanks why didn't you pass the "this" keyword into [].slice.call(arguments)? Observation: Math.min(...numArray) could also be substituted inplace of Math.min.apply(null, numArray)
I am not sure where I am in my JavaScript learning journey..suppose I practiced all these 52 Videos of advanced JavaScript and thoroughly understood the concepts all these 52 Videos where do I stand in my JavaScript journey...what should I do further to reinforce my learning of JavaScript so as to reach to an expert level?
I would suggest using those concepts after learning them . Either create your own tiny JS library. or use react where you can use your JS experience. With JS if you don't use it you lose it.
Sir, one confusion I have. When I am declaring a function like const fn = function(something) {} and call it with an object, javascript call function works, but when I try the same with arrow functions like const fn = something => {}, it doesn't work. I tried to print "this" in console with console.dir(this), and I got the object and window object for the two cases respectively. Please let me know why this thing is happening? Sir, your videos cleared many painful areas in JavaScript. Thank you so much.
all the concept is going to clear, but where should i will be use bind(). for me , bind has not clear. could you please elborate why new button object is loosely couple bonding with prototype?
Hi Techsith, I am getting "add clicked", when I calling "newButton.click();", how it is different from let looseClick = newButton.click; looseClick(); Running above code in chrome, also when I am executing the code in node console, getting exception i.e. => TypeError: Cannot read property 'content' of undefined. Why this is happening, please clarify.
looseClick is not part of the object anymore and not bound to the button so it wont work . And newButton.click() is part of the object . I am not sure why its not working in node. Try to debug in node.
Please try to provide links to which u refer in ur video... In this video u said u ll provide template string tutorial link 10:23 .. which u haven't provided.. Thanks
Is it correct to say that the spread operator (...) has reduced a lot of the complexity that was brought about by call/apply/bind ? For e.g. We can do min like this using spread operator in es6 :- Math.min(...numArray);
Sir, I have a same scenario, and want to unit test lion class. Problem is cat calls a function of mamal which returns a promise. How do I unit test this scenario from lion class.
You said we can use call/apply when we want to borrow functionality from another objects...But Why would you use call or apply to borrow functionality from other objects when you can just simply do obj.FunctionName() inside another object to borrow functionality from other object? Example: var obj = new function(){ this.prop = 'inside obj'; this.Add = function(a,b) {return a+b}; this.getinfo = function(){console.log('inside getinfo of obj object')}; } var anotherObject = new function(){ this.getaddition = function(a,b){ return obj.Add(a,b) }; //borrowed functonality from obj without using bind. } what would be the use case in above example where using call/apply/bind is a must ??
in your example the function that you are tying to call doesnt have 'this' so it would work . if you want to use one objects method on another object you have to call the new objects 'this' ..
But Dude the below code works fine.. Is this because i am not using "let" .. can u explain plz var test=function (name){ this.name=name; } test.prototype.click=function(){ console.log("===>"+this.name+" clicked"); } var b=new test('tesing'); b.click();
there shouldnt be any problem with let etither. the example you sent would work in any case . now you can do this and see if it works. this were you have to rebind the method back to the object. var test=function (name){ this.name=name; } test.prototype.click=function(){ console.log("===>"+this.name+" clicked"); } var b=new test('tesing'); var bc = b.click; bc();
what do you mean by translate your video to other language? like I translate what you said in this video to chinese and send to you, and you will put chinese subtitle as an option in the video???
I am not sure for how to do it for Chinese but youtube provides a link for translation of each video . here is a link for this video. ruclips.net/user/timedtext_video?ref=share&v=AYVYxezrMWA
i spend 1 hour to realize that these functions don't work using arrow function. Or i did wrong ? Do you have any tips that helps me to know when use i have to use arrow function and "normal function" ?
think of arrow functions pure functions that don't have its own this. so if you want to use this inside your function, don't use arrow function. I have a video on arrow function where I explain it.
mammal is a constructor but also a function that sets some property with this.legs = legs; and when you call from another function mammal.call(this,legs) which means you are calling mammal function on using this of which ever function calling it from. for more info on that you can refer to this playlist ruclips.net/p/PL7pEw9n3GkoW0ceMeoycg9D00YjPAbtvt
mammal is a function that does "this.legs = legs" so if i call it inside the cat. its like cat.legs = legs. becase 'this' inside cat is actually cat. make sense?.
@@Techsithtube you are doing a great job, Sir. Started watching all of your JS videos. All are awesome. But while understanding, getting confusions like button.prototype.'click ', after few min, I realize 'click ' is just a prototype property of the button. But i'm ok now. Thanks for the response. :p
I try to cut the dead space between sentences. and unfortunately the editor i am using to do that doesn't have the refined tool so its usually half a second off .
I was asked exactly this at the interview, today. I had no idea what they did. Now I know. Thanks!
Its good that you know now. :) You will be prepared for the next interview.
Thank you sir! Compared to other RUclips instructors, you are calm, collected and make everything easy to digest. You get a like from me!
Thanks for the very very positive comment. :) Keep on learning!
these are the exact questions being asked in mcq rounds and interviews and bro has done these videos 6 years back :))
that = this ---- The classic arrow functions solved that ugly design pattern. great video!
That's the thing i was going to mention with arrow functions you also don't need to use bind since the arrow functions keep the scope open to the father scope
man you're so underrated subscribed
Must watch video, if anybody want to understand call, bind and apply.
Thanks for watching!
"Binding outer this to inner this." That's a pretty good explanation for binding this.
Veronica, thanks for watching!
thank you for the awesome. you make javascript understand very easy.
Its very clear for call and apply. For bind I am very confused. Will do more exercise.
think of call and apply as renting tempararily . And bind is more like making it own.
great work
Helpful video
Thanks for these amazing Javascript series, these series are a real lifesaver!
great sir! keep going, this the real thing... supporting you till you get success, just keep making these awesome videos up
Thanks for all the support and thanks for watching! :)
Very useful..
good tips. thx
Great tutorial
Thank you! Cheers!
Amazing video, clears all the doubts in a very simple manner
Nearly 3 years before I saw his video related to Angular Testing. I was so impressed, I liked his teaching very much. I became his fan.
After 3 years, today I found this video of him. Sorry sir, but this comment's targeted to you. You please speak with your slang sir, don't try to create new slang.
Great and simple explanation thank you so much
Thanks for watching Yuvisaran.
Very helpful. Thanks. I think instead of using call/apply, better & shorter now to use es6 spread operator, to copy functionality from obj to obj.
Commonly used in react now.
Example:
function doSomething (x,y,z){ }
let args = [a,b,c]
doSomething(...args)
Thanks TechSith. Great Explanation!
Watched more than 10 videos on the same, but this one cleared my concepts
Binayak, I am gald that you got the concept. Thanks for watching! :)
Sir, your tutorials are amazing!
This is gold!
thank you for sharing valuable knowledge.
Nice tuto.thanks
you big bro your tutorials are rocking !! Respect !!
Very Helpful. Thank you Sir
Thanks for watching!
worth watching it .
excellent video god bless you
At 7:03 you had me laugh, great examples thanks
I am glad that you found it funny. thanks for watching! :)
You can do Math.min(...numArray); to get same results as apply method
Very nicely explained!
Thanks for watching!
Great video, thank you!
thank you
Thank you !!
To turn the argument into an array, we could also do make the argument a spread operator when passing it into the function then convert it into an array by saying:
Let arrArgs;
Let argsToArray= function(){
return arrArgs=[...arguments];
};
Right?
And then calling the function argsToArray(1,2,3) should console[1,2,3]?
Yep that would work .
With New ES 6 feature, to find out the Minimum value from array use REST operator let myarr= [1,2,3]; console.log(Math.min(...myarr)); Its just FYI for all
Great
@techsith Could also help us clear the difference between call, apply, bind vs prototype vs __proto__ ? As a developer, when/how should you use what?
Could we also use Array.from() to turn the arguments object into an array? ...
yes that should also give the same result.
This is better than any paid tutorial I have gone through. Thanks
why didn't you pass the "this" keyword into [].slice.call(arguments)?
Observation: Math.min(...numArray) could also be substituted inplace of Math.min.apply(null, numArray)
[].slice.call(arguments) just slices the argument object to an array. so there is not need to pass 'this' here.
I was hoping you will continue with angular 4.0,
I am still continuing with Angular tutorials . I will also release on other topics as well.
How are you defining "that" in the render function without using var, let or const?
Easier in ES6 with the spread/rest operator
function argsToArray(...args) {
console.log(args);
}
and
Math.min(...numArray)
Hehehe, I keep refactoring your functions to fat arrow as you type them unless they're not refactorable!! :0)
I am not sure where I am in my JavaScript learning journey..suppose I practiced all these 52 Videos of advanced JavaScript and thoroughly understood the concepts all these 52 Videos where do I stand in my JavaScript journey...what should I do further to reinforce my learning of JavaScript so as to reach to an expert level?
I would suggest using those concepts after learning them . Either create your own tiny JS library. or use react where you can use your JS experience. With JS if you don't use it you lose it.
Sir, one confusion I have. When I am declaring a function like const fn = function(something) {} and call it with an object, javascript call function works, but when I try the same with arrow functions like const fn = something => {}, it doesn't work. I tried to print "this" in console with console.dir(this), and I got the object and window object for the two cases respectively. Please let me know why this thing is happening? Sir, your videos cleared many painful areas in JavaScript. Thank you so much.
Btw, subbed!
About "bind", in myObj object I did render() {
this.asyncGet(this.parse);
} and it works. So why using bind?
Thanks for your great tutorial
what is asyncGet?
all the concept is going to clear, but where should i will be use bind(). for me , bind has not clear. could you please elborate why new button object is loosely couple bonding with prototype?
At 13.54 I can even use arrow function to get this context ? We don't need to use bind isn't it ?
Yes ruchi, you can use arrow function there.
Hi Techsith,
I am getting "add clicked", when I calling "newButton.click();", how it is different from
let looseClick = newButton.click;
looseClick();
Running above code in chrome, also when I am executing the code in node console, getting exception i.e. => TypeError: Cannot read property 'content' of undefined.
Why this is happening, please clarify.
looseClick is not part of the object anymore and not bound to the button so it wont work . And newButton.click() is part of the object . I am not sure why its not working in node. Try to debug in node.
Please try to provide links to which u refer in ur video...
In this video u said u ll provide template string tutorial link 10:23 .. which u haven't provided..
Thanks
Any idea why the first apply example doesn't work with arrow functions?
Is it correct to say that the spread operator (...) has reduced a lot of the complexity that was brought about by call/apply/bind ?
For e.g.
We can do min like this using spread operator in es6 :-
Math.min(...numArray);
yep, spread operators have some really good use. and it has simplify lots of complex things.
Sir, I have a same scenario, and want to unit test lion class. Problem is cat calls a function of mamal which returns a promise. How do I unit test this scenario from lion class.
Why when you call the mammal constructor you use this and legs and not only legs????????
@3:55 Javascript - weird language
why click loosely bounded to new object? 10:56
You said we can use call/apply when we want to borrow functionality from another objects...But Why would you use call or apply to borrow functionality from other objects when you can just simply do obj.FunctionName() inside another object to borrow functionality from other object?
Example:
var obj = new function(){
this.prop = 'inside obj';
this.Add = function(a,b) {return a+b};
this.getinfo = function(){console.log('inside getinfo of obj object')};
}
var anotherObject = new function(){
this.getaddition = function(a,b){ return obj.Add(a,b) }; //borrowed functonality from obj without using bind.
}
what would be the use case in above example where using call/apply/bind is a must ??
in your example the function that you are tying to call doesnt have 'this' so it would work . if you want to use one objects method on another object you have to call the new objects 'this' ..
Thank you for clearing the doubt here..
Who the hell are dislikers? what the heck you want more?
But Dude the below code works fine.. Is this because i am not using "let" .. can u explain plz
var test=function (name){
this.name=name;
}
test.prototype.click=function(){
console.log("===>"+this.name+" clicked");
}
var b=new test('tesing');
b.click();
there shouldnt be any problem with let etither. the example you sent would work in any case . now you can do this and see if it works. this were you have to rebind the method back to the object.
var test=function (name){
this.name=name;
}
test.prototype.click=function(){
console.log("===>"+this.name+" clicked");
}
var b=new test('tesing');
var bc = b.click;
bc();
Practical Applications for PROMISE plzzzz
what do you mean by translate your video to other language? like I translate what you said in this video to chinese and send to you, and you will put chinese subtitle as an option in the video???
I am not sure for how to do it for Chinese but youtube provides a link for translation of each video . here is a link for this video.
ruclips.net/user/timedtext_video?ref=share&v=AYVYxezrMWA
is there any upcoming React Series?
yes, I am going to start releasing by next week. Let me know if you have specific topics that you want to me to cover. Thanks for watching!
i spend 1 hour to realize that these functions don't work using arrow function. Or i did wrong ? Do you have any tips that helps me to know when use i have to use arrow function and "normal function" ?
think of arrow functions pure functions that don't have its own this. so if you want to use this inside your function, don't use arrow function. I have a video on arrow function where I explain it.
I’m trying to understand bind but I still don’t get it :l
Very difficult to understand. Please maybe make another video.
I am not that much clear with call,for call we are passing obj n value I donot understand this line mammal.call(this,legs) could u pls explain?
mammal is a constructor but also a function that sets some property with this.legs = legs; and when you call from another function mammal.call(this,legs) which means you are calling mammal function on using this of which ever function calling it from. for more info on that you can refer to this playlist ruclips.net/p/PL7pEw9n3GkoW0ceMeoycg9D00YjPAbtvt
didn't get how legs property became part of cat by calling mammal.call(this,legs) ? can you please explain the logic behind it?
mammal is a function that does "this.legs = legs" so if i call it inside the cat. its like cat.legs = legs. becase 'this' inside cat is actually cat. make sense?.
Yes it does make sense..Thank you:)
Hi sir , I want to translate into Telugu ,pls provide the link
After 5mins I felt like I was lost in desert , didn't understand this cat example at all😑
Do you stopped angular4
I am still continuing with Angular tutorials . I will also release on other topics as well.
techsith ok
Please don't use reserved key words for variable or function
I wonder which reserve keyword I used?
@@Techsithtube you are doing a great job, Sir. Started watching all of your JS videos. All are awesome.
But while understanding, getting confusions like button.prototype.'click ', after few min, I realize 'click ' is just a prototype property of the button.
But i'm ok now.
Thanks for the response. :p
It's hard for me to perceive real world usage each time
It is hard often times to times visualize application of such concepts. But, its heavely used in large projects.
Bind is so confusing
Stop comming in my youtube 😵
Honest question, why in most of the videos your sentences are cut off?
I try to cut the dead space between sentences. and unfortunately the editor i am using to do that doesn't have the refined tool so its usually half a second off .
Very nicely explained!
Thanks for watching! :)