code: function(options) {
          OpenLayers.Control.prototype.initialize.apply(this, [options]);
          this.options = options || {}; // TODO: this could be done by the super
          
          // set the source layer if provided
          if(this.options.source) {
              this.setSource(this.options.source);
          }
      }
docs: Constructor: OpenLayers.Control.Split
  Creates a new split control. A control is constructed with a target
  layer and an optional source layer. While the control is active,
  creating new features or modifying existing features on the source
  layer will result in splitting any eligible features on the target
  layer.  If no source layer is provided, a temporary sketch layer will
  be created to create lines for splitting features on the target.
  
  Parameters:
  options - {Object} An object containing all configuration properties for
  the control.
  
  Valid options:
  layer - {<OpenLayers.Layer.Vector>} The target layer.  Features from this
  layer will be split by new or modified features on the source layer
  or temporary sketch layer.
  source - {<OpenLayers.Layer.Vector>} Optional source layer.  If provided
  newly created features or modified features will be used to split
  features on the target layer.  If not provided, a temporary sketch
  layer will be created for drawing lines.
  tolerance - {Number} Optional value for the distance between a source
  vertex and the calculated intersection below which the split will
  occur at the vertex.
  edge - {Boolean} Allow splits given intersection of edges only.  Default
  is true.  If false, a vertex on the source must be within the
  <tolerance> distance of the calculated intersection for a split
  to occur.
  mutual - {Boolean} If source and target are the same, split source
  features and target features where they intersect.  Default is
  true.  If false, only target features will be split.
  targetFilter - {<OpenLayers.Filter>} Optional filter that will be evaluated
  to determine if a feature from the target layer is eligible for
  splitting.
  sourceFilter - {<OpenLayers.Filter>} Optional filter that will be evaluated
  to determine if a feature from the target layer is eligible for
  splitting.