[Codewars] Double Char (8 kyu) / JavaScript

https://www.codewars.com/kata/56b1f01c247c01db92000076

Codewars - Achieve mastery through coding practice and developer mentorship

 

DESCRIPTION:

Given a string, you have to return a string in which each character (case-sensitive) is repeated once.

Examples (Input -> Output):

* "String"      -> "SSttrriinngg"
* "Hello World" -> "HHeelllloo  WWoorrlldd"
* "1234!_ "     -> "11223344!!__  "

Good Luck!

 

코드

function doubleChar(str) {
  return str.split('').map(el => el.repeat(2)).join('');
}