Braces balancer

braces-balancer.js

var isBalanced = function(str) {
  var openers = '{[(<';
  var closers = '}])>';
  
  var stack = [];
  str = str.split('');
  for (var i = 0; str.length; i++) {
    var index;
    if (openers.indexOf(str[i]) != -1) stack.push(str[i]);
    else if ((index = closers.indexOf(str[i])) != -1) {
      if (stack.pop() != openers.charAt(index)) return false;
    } else {
      console.log('Unknown character!');
      return false;
    }
  }
  return stack.length === 0;
};

console.log(isBalanced('{[<><>]}')); // true
console.log(isBalanced('{[()]}')); // => true
console.log(isBalanced('{[{}][()]}')); // => true
 
console.log(isBalanced('{]}')); // => false
console.log(isBalanced(')({}}')); // => false
console.log(isBalanced('{{[(<>)]}')); // => false