Codewars JS

gistfile1.js

function order(words){
  // return empty string for undefined
  if (words === undefined) {
    return '';
  }
  
  let rval = [];
  let pieces = words.split(' ');
  for (let i=0; i<10; i++) {
    if (pieces.hasOwnProperty(i)) {
      let piece = pieces[i].match(/\d/);
      if (piece) {
        rval[piece[0]] = piece.input;
      }
    }
  }
  return rval.join(' ').trim();
}