// variable scope = where a variable is recognized // and accessible (local vs global) let x = 3; // global scope function1(); function function1(){ let x = 1; // local scope console.log(x); } function function2(){ let x = 2; // local scope console.log(x); }
This is the best and clearest explanation I can get on youtube!! Your reference of neighbour house makes so much sense to me. Thank you, you’re the best teacher bro🙏
what about variables declared in other files in global scope ? are they acceible outside that file in global scope ? what is diff between let and var ?
Hi Bro, couldn't you declare (even if it's bad practice) a local variable to be global inside of a function? For example in python you do: global x = 5. even if it is declared inside of a function it is now global and accessible everywhere. Much love ❤
i know it's been 8 months since you asked but i was just playing with the scope and variable and noticed that if you do not use let ,var ,const to declare a variable inside a function it creates a global variable which can be accessed from anywhere Example: function myFunc() { num = 3; // didn't use var let const before the variable name // also works with function sayhi = function () { console.log("sayHi"); }; } myFunc(); // You have to first call this function // not calling will result in not defined console.log(num); // it prints the value i.e, 3 even though num is inside function myFunc sayhi(); // you can call this function without error // Not using "let" "const" "var" when declaring variable inside function creates global variables
Variables defined with `let` aer scoped to blocks and functions, and can be reassigned Variables defined with `const` are scoped to blocks and functions, and cannot be reassigned Variables defined with `var` are scoped to functions or global (if define in block), and it can be reassigned ``` // Block { var aVar = 1; console.log('aVar', aVar); let aLet = 2; console.log('aLet', aLet); const aConst = 3; console.log('aConst', aConst); } console.log('aVar', aVar); // console.log('aLet', aLet); // Fails // console.log('aConst', aConst); // Fails // Function function myFunc() { var aFuncVar = 10; console.log(aFuncVar); } myFunc(); // console.log(aFuncVar); // Fails ```
// variable scope = where a variable is recognized
// and accessible (local vs global)
let x = 3; // global scope
function1();
function function1(){
let x = 1; // local scope
console.log(x);
}
function function2(){
let x = 2; // local scope
console.log(x);
}
3:27 is a global scope
This has to be the best explanation for scoping on youtube. I love the examples!
Best incremental teaching! You are a gifted teacher.
This is the best and clearest explanation I can get on youtube!! Your reference of neighbour house makes so much sense to me. Thank you, you’re the best teacher bro🙏
Yes! Bro Code is a master explainer!
I am sure he knows about Feynnman's technique.
I love the way how you explane that!
This is my seal. I have watched the entire video, understood it, and I can explain it in my own words, thus I have gained knowledge. This is my seal.
One of the best explanation thanks Bro
Thank you for your tutorials man!
Very Good Explanation.
Thanks !! good explanation
really awesome you are the best ever
Well done man thanks ❤
Great man
The stalker analogy 😂😂😂😂
Exactly 20000% confident
Thank you 🎉
what about variables declared in other files in global scope ? are they acceible outside that file in global scope ? what is diff between let and var ?
thank you Bro!
Hi Bro, couldn't you declare (even if it's bad practice) a local variable to be global inside of a function? For example in python you do: global x = 5. even if it is declared inside of a function it is now global and accessible everywhere. Much love ❤
i know it's been 8 months since you asked but i was just playing with the scope and variable and noticed that if you do not use let ,var ,const to declare a variable inside a function it creates a global variable which can be accessed from anywhere
Example:
function myFunc() {
num = 3; // didn't use var let const before the variable name
// also works with function
sayhi = function () {
console.log("sayHi");
};
}
myFunc(); // You have to first call this function // not calling will result in not defined
console.log(num); // it prints the value i.e, 3 even though num is inside function myFunc
sayhi(); // you can call this function without error
// Not using "let" "const" "var" when declaring variable inside function creates global variables
Variables defined with `let` aer scoped to blocks and functions, and can be reassigned
Variables defined with `const` are scoped to blocks and functions, and cannot be reassigned
Variables defined with `var` are scoped to functions or global (if define in block), and it can be reassigned
```
// Block
{
var aVar = 1;
console.log('aVar', aVar);
let aLet = 2;
console.log('aLet', aLet);
const aConst = 3;
console.log('aConst', aConst);
}
console.log('aVar', aVar);
// console.log('aLet', aLet); // Fails
// console.log('aConst', aConst); // Fails
// Function
function myFunc() {
var aFuncVar = 10;
console.log(aFuncVar);
}
myFunc();
// console.log(aFuncVar); // Fails
```
I thought you would explain var keyword
creepy guy ahahaha maybe he is just waiting for the bus (?)