if (typeof String.trim == 'undefined') {
  String.prototype.trim = function () {
    return this.replace (/^\s+|\s+$/g, '');
  };
}

function Transition (e) {

  var prop = e.style.transitionProperty.split (',');
  var dur  = e.style.transitionDuration.split (',');
  this.e = e;

  // assert (true, (prop.length == dur.length)); 

  for (var i = 0; i < prop.length; i++) 
    this[prop[i].trim ()] = dur[i].trim ();

  return this;

}

Transition.prototype = {
  getProperties: function () {
    var names = [];
    for (var p in this) 
      if (typeof this[p] == 'string') 
        names.push (p);
    return names;
  },
  applyTransitions: function (o) {
    var names = this.getProperties ();
    this.e.style.transitionProperty = names.join (', ');
    var dur = [];

    for (var n in names) 
      dur.push (this[names[n]]);

    this.e.style.transitionDuration = dur.join (', ');

    if (typeof o == 'object')
      // ({width: '50px', height: '200px'})
      for (var p in o)
        this.e.style[p] = o[p];
  }
};