Kata

Your task is very simple:
Write a function hasOneChar returning:

• true if the given string contains the same character repeated all along the string
• false otherwise.

For instance:

hasOneChar('aaaaa'); //true
hasOneChar('aaaab'); //false
hasOneChar('bbbbb'); //true
hasOneChar('bbabb'); //false

Of course, what comes in mind first is a loop. But the purpose of this Kata is to test your creativity.
You have to achieve it without using any loops.

Corner cases: the function hasOneChar should return true if the string contains one single character.

Be creative!