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Can we access a variable declared using 'var' keyword inside a block?

A variable is declared using 'var' keyword inside a block ( {...} ). Can we access that variable outside the block? I searched on several websites and the answer was 'yes'. 'Yes we can access the variable' it said. But when I executed this on a browser console it said "the variable is not defined". Any thoughts why this is so?

Here's the screenshot of the same

1

I expected it to give 12345.

Solution

  • A variable is declared using 'var' keyword inside a block ( {...} ). Can we access that variable outside the block? I searched on several websites and the answer was 'yes'.

    tldr; It's more precise to say Yes, unless that block is a function body.

    var scopes a variable to the nearest function.

    The body of the function (excepting some arrow functions) is a block.

    Not all blocks are associated with functions.

    {
    var inBlock = 1;
}

console.log(inBlock); // This logs 1

function aFunction() {
    var inFunction = 2;
}

aFunction();

console.log(inFunction); // This triggers a reference error