function Stack(values) {
	  var index = -1,
	      length = values ? values.length : 0;

	  this.clear();
	  while (++index < length) {
	    var entry = values[index];
	    this.set(entry[0], entry[1]);
	  }
	}
Creates a stack cache object to store key-value pairs.

@private
@constructor
@param {Array} [values] The values to cache.