Lexical scoping and Closure | chai aur #javascript

#javascript #hindi
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[muhammadadil-orkb]

0:00 Introduction
1:55 Reading the MDN docs
3:23 Lexical Scoping
14:00 Closure

[vikasmaur]

0:00 Introduction
1:55 Reading the MDN docs
3:23 Lexical Scoping
14:00 Closure
18:09 Practical Implementation

[momlifevlogging]

I have never never understood the basics of these things like closures, lexical scoping and data structure etc. but this guy deserves hats off.... literally you need a gold medal for teaching in such an awesome way. i am first time commenting on any youtube coding video.

[shubhamkumarjha]

0:00 Introduction
1:55 Reading the MDN docs
3:23 Lexical Scoping
14:00 Closure
18:09 Practical Implementation

very very helpful playlist Thank you so much sir for this Premium course on javascript for free..

[MuhammadMasood-pr]

Lexical scoping completed at time stamp 13:30

[prakharsinha]

trust me sir! you will be known forever for this Javascript series! The Best on the planet!

[NaumanMalik-ee]

I tried many videos and channels for closures but finally I found this guy. Thank you so much sir

[abhishekkumargupta]

I have not shared your videos links to anyone but I have recommended many friends to watch your videos . if they don't know any topic and try to ask me then I use to say "AAGAR AAP NE CHAI AUR CODE PE HITESH SIR SE PDE HOTE TO MERE SE NHI PUCHTE ", No doubt you are super. keep making videos and get motivated . I started watching your videos 3 years back but i was never serious but now I am int the stream. Once again thank you sir.

[SarveshKumar-]

00:03 The video will cover two interesting topics: closure and lexical scoping.
01:47 Understanding closure and its access to outer function scope with MDN docs.
05:36 Lexical scoping does not allow access to variables declared inside a function in the outer scope.
07:55 Inner functions have their own execution context and share memory with the outer function.
11:51 Understanding Outer and Inner Function.
13:37 Explanation of lexical scoping and its significance. Detail explanation of closure through an example
17:32 Lexical scoping and closure return the entire lexical scope of a function when a complete function is returned.
19:14 Using onClick event and changing background color in JavaScript
22:27 Understanding the difference between a function and a reference to a function.
24:03 In Summary Functions have access to variables defined in their outer scope.
Closure allows a function to retain access to variables from its lexical scope

[AbhishekKumar-cdgg]

yeah definetly sir it is one of the good examples of closures but still we can do the same task with the help of arrow function also
here the code

const orange =
const green =

orange.onclick = () => clickHandler("orange")

green.onclick = () => clickHandler("green")

function clickHandler (color) {

}

[Hafijur]

🎯 Key Takeaways for quick navigation:

00:44 🎉 *Introduction to Closure and Lexical Scoping*
- Acknowledgment of the importance of Closure and Lexical Scoping.
- Announcement of the continuation of the JavaScript series with a focus on Closure and Lexical Scoping.
01:12 📘 *Exploring Lexical Scoping*
- Definition and role of Lexical Scoping in JavaScript.
- Brief mention of a mini-project for real-world implementation understanding.
01:54 🔍 *Setting the Stage for Closure Understanding*
- Teasing the concept of Closure and the need to understand it.
- Reflecting on the engagement and positive response from the audience.
02:22 🔒 *Introduction to Closure*
- Defining Closure as a combination of functions bundled together with references to the surrounding state.
- Acknowledging the initial complexity of the definition.
02:37 🌐 *Understanding Closure Basics*
- Explanation of Closure concept involving outer and inner functions.
- The accessibility of the outer function's scope from the inner function is clarified.
03:05 🧠 *Brief on Creation Time and Closure*
- Introduction to the concept of creation time in Closure.
- Teaser about the interesting aspects of creation time, to be discussed later.
03:32 📖 *Lexical Scoping and Example Walkthrough*
- Initiation of the Lexical Scoping explanation.
- Importing and pasting code into a new folder for better organization.
04:29 🛠️ *Code Refinement and Documentation*
- Correction of indentation for better code readability.
- Preference for using "let" over "var" for variable declaration.
05:11 🖥️ *Understanding Function Scope*
- Declaration and explanation of the "displayName" function.
- Clarification of the scope of the "displayName" function and where the variable "name" is accessible.
05:40 🔍 *Exploring Scope Access in Functions*
- Introduction to the importance of function scope and access to variables.
- Discussion on the theoretical aspect and justification of variables being unavailable outside the function's scope.
06:22 🧐 *User Input and Scope Access*
- Exploring the impact of declaring variables inside functions on their accessibility.
- Discussion on whether the "username" variable declared inside the function will be accessible outside.
07:05 🔒 *Inner Function and Scope Locking*
- Introduction to the concept of an inner function, named "inner, " declared inside the "outer" function.
- Explanation that the "inner" function locks the access to the "username" variable within the "outer" function.
07:55 🔍 *Accessing Variables in Nested Functions*
- Declaration of the "username" variable at line 25 and line 31 within different functions.
- Explanation of the challenge of accessing the "username" variable inside the inner function.
08:08 🤔 *Inner Function's Access to Variables*
- Highlighting the availability of "username" inside the inner function.
- Discussion on whether the outer function should also have access to the "username" variable.
08:50 🔗 *Lexical Scoping and Variable Sharing*
- Introduction to the concept of lexical scoping and how it affects variable accessibility.
- Explanation of separate execution contexts for each function loaded and their shared memory.
09:44 🔄 *Inner Function's Access to Outer Variables*
- Verification of the absence of local variables within the inner function.
- Exploration of how the inner function can access variables declared in the parent function (lexical scope).
10:25 🌐 *Accessing Variables in Nested Functions*
- Explanation of how outer function variables are accessible within nested functions.
- Demonstration using the "username" variable and accessing it from both outer and inner functions.
11:08 🧐 *Nested Functions and Variable Accessibility*
- Discussion on the accessibility of variables based on the parent-child relationship in nested functions.
- Introduction of the concept of equality in variable access within a family analogy.
11:49 🔐 *Securing Variables within Inner Functions*
- Exploration of variable access within the inner function using the "secret" variable.
- Demonstrating restrictions on accessing the "secret" variable from the outer function.
12:31 🤝 *Shared Variable Access in Nested Functions*
- Investigating whether the outer function has access to the "secret" variable declared within the inner function.
- Emphasis on the technical exploration of variable accessibility.
12:58 🧸 *Metaphor: Sharing Toys and Ice Cream*
- Introduction of a metaphor where personal properties (toys and ice cream) can be shared among family members.
- Clarification on the limitations of sharing certain personal properties, emphasizing equality.
13:41 🚪 *Closure Introduction and Community Help*
- Announcement of the completion of Part 1 and a request for timestamps to facilitate navigation.
- Invitation for viewers to assist each other in understanding the concepts discussed.
14:08 🔍 *Explaining Closure with an Example*
- Explanation of closure using an example involving Mozilla Firefox.
- Demonstrating the attempt to understand closure through practical coding analysis.
15:06 🔄 *Inner Function Returning Value*
- Highlighting the concept that inner functions have access to the outer function's scope.
- Introduction of the interesting concept of returning a function within another function.
15:46 🧐 *Understanding Function Scope*
- Explanation of function scope and its duration until execution.
- Introduction of the challenge when the function's scope disappears after execution.
16:00 📜 *Closure Concept in JavaScript*
- Introducing the concept of closure in JavaScript.
- Explaining how closure involves removing the execution context but retaining memory references.
16:28 🔍 *Memory Reference in Function Execution*
- Explaining the importance of memory references in the execution of functions.
- Demonstrating the creation of a function (by function execution) and its subsequent memory reference.
17:08 🔄 *Practical Example with Mozilla Display*
- Demonstrating a practical example with Mozilla display to solidify the understanding of lexical scoping.
- Highlighting the significance of outer and inner functions and their shared lexical scope.
17:36 🤔 *Closure and Practical Implementation*
- Defining closure as the return of a function with its entire lexical scope.
- Illustrating the practical implementation of closure with a detailed explanation.
18:04 📚 *Practical Implementation Scenario*
- Addressing the challenge of practical implementation of lexical scoping and closure.
- Emphasizing the importance of real-world scenarios for a deeper understanding.
18:33 🛠️ *Building a JavaScript Example*
- Creating a simple JavaScript example with multiple buttons.
- Assigning unique IDs to orange and green buttons.
19:02 🧩 *Implementing Button Click Functionality*
- Defining the functionality for the orange and green buttons.
- Assigning a background color change on click for the orange button.
19:59 🖌️ *Styling and Functionality Refinement*
- Styling the buttons by changing background colors and text.
- Refining the code to ensure smooth implementation and visual appeal.
20:26 🚀 *Scaling for Multiple Buttons*
- Discussing the process of scaling the implementation for multiple buttons.
- Providing a glimpse into handling a larger number of buttons efficiently.
20:42 🔄 *Repeating Click Handler Logic*
- Discussing the challenge of repetitive code when dealing with multiple buttons.
- Introducing the "DRY" (Don't Repeat Yourself) principle.
21:11 🛠️ *Implementing Generic Click Handler*
- Introducing the concept of a generic click handler function.
- Emphasizing the ability to dynamically determine which button was clicked.
21:51 📝 *Dynamic Color Injection*
- Utilizing variables and parameters for flexible and adaptable code.
22:33 🚀 *Refining Click Handler*
- Refining the click handler function with proper references and definitions.
- Highlighting the importance of passing values correctly to the click handler method.
23:01 🔍 *Handling Multiple Buttons*
- Discussing the need for a global event handler for managing multiple buttons.
- Introducing the "on click" global event handler and its role.
23:15 🎨 *Dynamic Styling and Lexical Scoping*
- Demonstrating the dynamic change of colors (orange and green) in response to different button clicks.
24:13 🔄 *Modifying Function Definition*
- Discussing the necessity of modifying the definition of the function to address the problem.
24:52 🌐 *Lexical Scoping and Closure Relationship*
- Explaining the relationship between lexical scoping, closures, and the access to variables.
25:34 🔍 *Real-world Application of Closures*
- Encouraging viewers to build their own projects to encounter and understand real-world problems.
25:47 🌐 *Importance of Variable Access in Functions*
- Discussing the significance of variable access in functions.
26:02 🔄 *Handling Variables with Closures*
- Illustrating the use of closures to handle variable access effectively.

Made with HARPA AI

[biswajitnayak]

0:00 introduction
1:55 Reading Mdn docs
3:23 Lexical scoping
14:00 closures

[anilray]

Aaapko hirday se naman hai to interview dene wale hi nahi balki interview lene wale ko bhi sikhna chahiye....aapka video to mai dekhta and like share karta rahta hu but ispe to aapne comment likhne ko majbur hi kar dia

[ArunChauhan-fy]

0:00 introduction
1:55 Reading the MDN docs
3:23 Lexical Scoping
14:00 Closure..

[Dev-Phantom]

application of this Lexical scope was totally new for me. very intersting

[rajanbhai]

1:55 Reading the MDN docs
3:23 Lexical Scoping
13:33 Closure
18:09 Practical Implementation

[omaewamoushindeiru]

25:40 so here's the explanation and my understanding of this particular example ---
The onclick here requires a reference of a function so that it can call it when the click event occurs on corresponding button, we always pass reference in this type of situation to prevent the function to get executed immediately.
But the problem is we can't just pass the reference of the function because as we know it requires the color in the form of parameter and we are noy storing the reference in variable like structure such as let refHolder = clickHandler; so we can't call the refHolder later with the color parameter later in code such as refHolder('blue').
In reality, we are giving the reference to onclick which doesn't have an in built functionality or human intelligence to call this clickHandler with argument based on the button.
So now we actually have a tiny war between onclick() demanding a reference and clickHandler(color) which demands to be called with a parameter only otherwise error.

Now in order to fullfill the demand of bith entities, we can we will indeed call the clickHandler() with color parameter passed ( demand fulfilled ) but at the same time we will do something that a reference is given to onClick function ( which it strictly demands ), we will return reference of an inner function which does the main work or logic( demand fulfilled ) ( Very important thing to note here is this could not have been achieved without the feature of lexical scoping )

[ImSRJY]

यूट्यूब पर कोचिंग का खेल तो चलता रहेगा, कोर्स आएंगे, जाएंगे.. कभी फ्री बनेंगे कभी पेड लेकिन ये चाय और कोड रहना चाहिए इसका बेशकीमती जावास्क्रिप्ट का कोर्स अमर रहना चाहिए। ❤❤

[sudiptobose]

13:07 you are the best. baki youtubers k video ko dekh kar samjh nahi aya but yeh video dekh kar mere atma ko santushti mil gaya.

[ibcer.shubhamsinghbadabusi]

1.5x me bhi ek hi baar me samajh aa gaya. waah kya chai hai haha. Thank you so much sir..