binarySearch.js

Array.prototype.binarySearch = function binarySearch(find, comparator, insert) {
  if (!comparator) {
    comparator = function(a,b) {
      return ((a == b) ? 0 : ((a < b) ? -1 : 1)); };
  }
  var low = 0;
  var high = this.length - 1;
  var i, comparison;
  while (low <= high) {
    i = parseInt((low + high) / 2, 10);
    comparison = comparator(this[i], find);
    if (comparison < 0) { low = i + 1; continue; };
    if (comparison > 0) { high = i - 1; continue; };
    return i;
  }
  
  if (insert) {
    return low;
  }
  
  return -1;
};

Array.prototype.orderedInsert = function orderedInsert(value, comparator) {
  var index = this.binarySearch(value, comparator, true);
  this.splice(index, 0, value);
  
  return index;
};

Array.prototype.orderedDelete = function orderedDelete(value, comparator) {
  var index = this.binarySearch(value, comparator);
  if (index >= 0) {
    this.splice(index, 1);
  }
  return index;
};