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JavaScript

Posted by David Trejo
David Trejo
19,914 Points

Scope Chain Question

Hello,

I have a question about how this script works. I am trying to understand why "grandparent();", "parent();", and "child();" are needed for console.log in the child function to work.

var myVar = "A global variable";

function grandparent(){

    function parent(){

        var myVar = "Variable local to parent scope";

        function child(){
            console.log(myVar);
        }
      child();
    }
  parent();
}
grandparent();
Jason Anello
Jason Anello
Courses Plus Student 94,610 Points

Hi David,

Could you try clarifying what you mean in your question? Are you asking why the console.log outputs what it does?

Maybe if you can show the context of where this code came from it will help.

1 Answer

Casey Ydenberg
Casey Ydenberg
15,622 Points
Casey Ydenberg
Casey Ydenberg
15,622 Points 
function parent(){

    var myVar = "Variable local to parent scope";

    function child(){
        console.log(myVar);
    }
    child();
}
parent();

Will work. However

var myVar = "A global variable";

function grandparent(){

    function parent(){

        var myVar = "Variable local to parent scope";

        function child(){
            console.log(myVar);
        }
      child();
    }
}
parent();

will not. The variables and functions defined within grandparent cannot be accessed by the scope outside of it.