JavaScript - Why is this function declaration created in a function expression “undefined”?

Question

I\'m just trying to get my head around this function expression.

It seems that if I create a function expression (p) that seems to contain a function de

Answer 1

You can think of it as an anonymous function.

The reason that this is valid is because the local function name a can be used within the function declaration for recursion, but is not valid outside of this scope.

https://developer.mozilla.org/en-US/docs/JavaScript/Reference/Operators/function