define(['./_cb', './_getLength', './contains', './isBoolean'], function (_cb, _getLength, contains, isBoolean) {

  // Produce a duplicate-free version of the array. If the array has already
  // been sorted, you have the option of using a faster algorithm.
  // The faster algorithm will not work with an iteratee if the iteratee
  // is not a one-to-one function, so providing an iteratee will disable
  // the faster algorithm.
  function uniq(array, isSorted, iteratee, context) {
    if (!isBoolean(isSorted)) {
      context = iteratee;
      iteratee = isSorted;
      isSorted = false;
    }
    if (iteratee != null) iteratee = _cb(iteratee, context);
    var result = [];
    var seen = [];
    for (var i = 0, length = _getLength(array); i < length; i++) {
      var value = array[i],
          computed = iteratee ? iteratee(value, i, array) : value;
      if (isSorted && !iteratee) {
        if (!i || seen !== computed) result.push(value);
        seen = computed;
      } else if (iteratee) {
        if (!contains(seen, computed)) {
          seen.push(computed);
          result.push(value);
        }
      } else if (!contains(result, value)) {
        result.push(value);
      }
    }
    return result;
  }

  return uniq;

});
