Yep, but see above; '1234' is still a string with a length of 4, so it meets the criteria.

The kata never stated that the friends' names should be actual real-world names, so based on the criteria you shouldn't discriminate against strangely named people (lookin' at you, Elon :P).

In a lot of lower-level kata, type safety isn't the point of the puzzle or tested against in the solution, so there's a lot of code golf.

liked your solution! however wouldn't the friend '1234', still pass ?? it's a string after all