"Input strings will only contain letters."

then this guy only completed 7 Katas lol. how ironic

How about the name with number ?

Make use of Type Coercion is clever

This is the most clear solution I have seen for this problem, thanks!

Can you tell me why ? Just want to know ^^

Great solution, thank you. I overcomplicated myself using .split("") and a condition but this is smart. Gotta remember about filter.

Easy to read and understand compared to the other solutions though it will have overall time complexity is O(n).

Names with numbers will be a trend .. apparently

Description says "a name has exactly 4 letters in it". Not numbers.

The fact that this question even gets asked is an indication that this solution is less than ideal.

Gonna start using this thank you

What an es5 monstrosity