Textual Class Dictionary

 // COM1205 Class Dictionary - DemDraw Application
//
// Modification History:
//
// 11/16/95 @ 10:00 by Ron
// added Coodinates_List and Term
// renamed vn_position to vn_offset
// renamed e_position to en_offset
//
// 11/21/95 @ 9:32 pm  by Tom Kneeland (tomk)
// Documented changes made for Use Case 2.  These Changes include
//	Changed Coordinates to have a DemString datamember, as opposed to
// 	two DemNumbers.  It was determined that the C++ code would never have
//	to change the values stored in this object, therefore we could store
//	the exact string that tcl needed to draw verticies and labels.  This
//      change made all interaction to tcl easier.
//
//	Also added a  Coordinates object to support lines with
//      bends.  tcl will generate the actual list of points to be stored in
//      this string.  This datamember is optional, since lines can be strait.
//
//      Made a vertex position, and a vertex name position optional.  This
//      allowed the demeter-input file to be modified, so that whole verticies
//      did not have to be specified when declaring edges.

Graph = "Class Dictionary Graph"
           < vertices > Vertex_List
           < edges > Edge_List .

Edge :   AltEdge
        | ConstEdge
        *common*
	  "from"     < from > Vertex
	  [ "Bendpoints" < middlepoints > Coordinates ] 
	  "to"    < to > Vertex .

Edge_List ~ "Edge" "List" Edge  { Edge } .

Vertex_List ~ "Vertex" "List" Vertex  {  Vertex } .

Vertex :  AltVertex
        | ConstVertex
	| Term
        *common*
          < vertexname > VertexName
          [ "vertex_pos" < position > Coordinates ] .

AltEdge = "AltEdge" .

ConstEdge = "ConstEdge"
            < edgename > EdgeName .

ConstVertex = "ConstVertex" .

AltVertex =  "AltVertex" .

Coordinates =  DemString.

VertexName =  < name > DemIdent
              [ "name_pos" < vn_offset > Coordinates ] .

EdgeName =    < name > DemIdent 
	      "name_pos" < en_offset > Coordinates .

Term =    "TermVertex" .