Return value of recursive function is 'undefined'

Question

Whenever I execute this snippet the console.log before return returns the array with 20 times the value 23. However console.log(Check(users, 0, 20)); returns only 'undefined'.

What am I doing wrong?

var users = [23, 23, 23, 23, 23, 23, 23, 23, 23, 23]; console.log(Check(users, 0, 20));  function Check(ids, counter, limit){     ids.push(23);      // Recursion     if (counter+1 < limit){         Check(ids, counter+1, limit);     }     else {         console.log(ids);         return ids;     } } 

Answer 1

You forgot to return a result from the point, where you entering recusrion.

var users = [23, 23, 23, 23, 23, 23, 23, 23, 23, 23]; console.log(Check(users, 0, 20));  function Check(ids, counter, limit){     ids.push(23);      // Recursion     if (counter+1 < limit){         return Check(ids, counter+1, limit); // return here!     }     else {         console.log(ids);         return ids;     } }  

But return value seems useless, cause' your function altering initial array as well.