Check if a string ends with another.

confirmEnding.js

function confirmEnding(str, target) {
  var counter = 0;
  strLastCharPosition = str.length - 1;
  targetLastCharPosition = target.length - 1;
  while (counter <= target.length &&
        (target[targetLastCharPosition] === str[strLastCharPosition])) {
    counter++;
    strLastCharPosition--;
    targetLastCharPosition--;
  }
  return counter === target.length;
}

Hmmm.. meh. But it's just the first approach. I want to make the same behavior using a functional one.