Value Types and Reference Types in JavaScript

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[@trappedcat3615]

x = x.toUpperCase() is the same as x.title = x.title.toUpperCase(). Both are mutable when we reassign a value.

[@user-xs3ic2hi9o]

im agree. The example is not the best... It is not correct, because i can say:"Reference Types are Immutable" because you run this: var x = {title: 'apple'}; x.title.toUpperCase(); and the title attribute does not change: x.title -> "apple"

[@llimacruz]

At the first time I also thought it was wrong, but look what I've found: "Consider an integer like var x = 1 - if I write x += 1, I haven’t incremented the number 1 itself, I’ve just changed the variable x to have a new value, 2." Got it? smallcultfollowing.com/babysteps/blog/2014/04/01/value-types-in-javascript/ I know that Mosh wouldn't make a mistake about it.

[@romainvincent7346]

I believe the very importance of value/reference comes with functions. Here is an example : x = "foo" y = { title: "foo" } (function(param){ param = 'bar' }(x)) // x == foo (function(param){ param.title = 'bar' }(y)) // y == bar First case, nothing changed because we changed a value which exists only inside the function block. But for the second case, we had a reference and we indeed modified the property title of the referenced object.

[@mironoordzij4089]

I mean he just reassigned the veriable being referenced, you can do the exact same thing with a primitive. Different? var x = 'apple' document.write(x) document.write(x.toUpperCase()) document.write(x) x = x.toUpperCase() document.write(x) document.write('') var y = {fruit:"melon"} document.write(y.fruit) document.write(y.fruit.toUpperCase()) document.write(y.fruit) y.fruit = y.fruit.toUpperCase() document.write(y.fruit)

[@jyotirmoymukhopadhyay5077]

var s = "hi" var s1 = s console.log(s1) s = s.toUpperCase() console.log(s1) var obj1 = { name: "Tyler", age: 30, hobbies: ["running", "coding"] } var obj2 = obj1 console.log(obj2) obj1.age = obj1.age + 1 console.log(obj2) i think this can be a good example @@llimacruz

[@user-uo9rz2fe9h]

To explain like a boss.

[@aryashacharya_world7143]

thanks you sir its very helpfull...and first time i am commenting on any video.great work.

[@MoT-MasterOfThings]

Very clear explaination

[@sanfordhoffman2392]

Great explanation

[@08-avinashs10]

Fabulous Mosh 😀 you make it so simple

[@keifer7813]

What a great video. I understand it now

[@mviniciuspolegario4794]

Amazing!!!!

[@adrian-4767]

Amazing! :D

[@shyamraosravanth1954]

good explanation sir

[@javascript_developer]

Great. Thanks. Is value types and primitive types are same?

[@AbdullahAtya]

This is really helpful :)

[@BlockchainDaddy]

Subbed!

[@waex7089]

thanx

[@sardarzain2551]

Amazing 🤩🤩🤩🤩

[@07UMARJAN]

hello Mr. Mosh, are you planing to do any pluralsight course soon? thanks

[@07UMARJAN]

Like for instance , " Xamarin Forms Tutorial: Build Native Mobile Apps with C#" could have a playlist seprately("Xamarin Tutorial") like "Backbone.js Tutorial". Thank you

[@pedroagma4417]

Would anybody know what "text editor/console" Mosh uses? It seems useful, having results calculated and everything but: what does he use? Thank you!

[@simasgradeckas4259]

It seems just like a built-in browser console :)

[@sreenivasulugattu2936]

However, if we compare x.title === y.title, it will return true;

[@TT-ud5gf]

Is string really a value type?

[@javascript_developer]

That is what mentioned in the video. If a two same string variable are compared to each other , they return true

[@AlvaroDoune]

please, make a tutorial of Firebase! many thanks

[@AlvaroDoune]

great mosh, but I already bought 2 courses and I don't need to learn Angular because I work every day with this framework in my job! :)

[@AD-wg8ik]

let x = 'apple' x = x.toUpperCase() x = 'APPLE ' That's essentially what you did for the object.

[@pedro7851]

Yeah, he didn't assign the x.toUpperCase() to the x variable like he did to the title property of the x object...