Flash MX 2004.
halfEdge.getPrev()
None.
A HalfEdge object.
Method; gets the preceding HalfEdge object on the current contour. Note: Although half edges have a direction and a sequence order, edges do not.
The following example stores the previous half edge of the specified contour in the prevHalfEdge variable:
var shape = fl.getDocumentDOM().selection[0];
var hEdge = shape.edges[0].getHalfEdge( 0 );
var prevHalfEdge = hEdge.getPrev();