Question

I found the following JavaScript example here:

https://developer.mozilla.org/en-US/docs/JavaScript/Guide/Values,_variables,_and_literals

/**
 * Example 2
 */
// will return a value of undefined
var myvar = "my value";

(function() {
  console.log(myvar); // undefined
  var myvar = "local value";
})();

Why does console.log(myvar) return "my value" and not undefined as specified in the comment?

I tested it in Firefox and Chrome and I get the same result.

Answer 1

var myvar = "my value";

(function() {
  console.log(myvar); // undefined   
  var myvar = "local value";
})();​

Indeed, the output is undefined.
I think it’s because myvar is redefined in the scope.

But if you comment myvar in the function scope, output will be “my value”.
Like if myvar is a global variable.

–> Try !