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27 Let and Const Examples.html
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27 Let and Const Examples.html
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<!DOCTYPE html>
<html lang="en">
<head><title>Let and Const Examples</title>
</head>
<body>
from N.S video : let and const
note: Before seeing this code , please read previous code explanation full
<script>
console.log(b); // o/p: undefined
var b=10;
console.log(b); // o/p:10
//console.log(a); // ReferenceError: Cannot access 'a' before initialization
let a=5;
console.log(a); // o/p : 5
//console.log(c); // ReferenceError: Cannot access 'c' before initialization
const c=15;
console.log(c); // o/p : 15
/*
Hoisting of let
Just like var, let declarations are hoisted to the top.
Unlike var which is initialized as undefined, the let keyword is not initialized.
So if you try to use a let variable before declaration, you'll get a Reference Error.
same is in case of const
but why, because in case of var b , memory is assigned to b and this variable b was
attached to global object.
But in case of let and const they are also allocated memory, but they are stored in the
different memory space and not in the global object and you can't access this memory space
before putting some value in it that's why var : hoisting shows : undefined
and let and consts : hoisting shows: Error
*/
</script>
</body>
</html>