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javascriptfunctionhoisting

What is difference between hoisting var x = 3 and var x

Consider the two following snippets

function x(){}
var x = 3;
console.log(typeof x) //"number"

This happens because function declarations are hoisted first.

function x(){}
var x;
console.log(typeof x) //"function"

I expect the type to be undefined because var x; creates a variable with undefined value.

Solution

  • var x declares the variable xbut doesn't assign anything to it.

    If you did set its value to undefined, then that would be undefined:

    function x(){}
var x = undefined;
console.log(typeof x) //"undefined"

    So what you made in your example is just 

    var x;
function x(){}

    While in my example it becomes 

    var x;
function x(){}
x = undefined;