27 Let and Const Examples.html

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    <head><title>Let and Const Examples</title>
    </head>
    <body>
        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 way assigned to b and this variable b was 
            attached to global object.
            But in case of let and const they are also allocated with 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> 