domain MapColoring
{
   Color ::= { red, green, blue, gray }.
   
   primitive AT ::= (Color).
   primitive BE ::= (Color).
   primitive CH ::= (Color).
   primitive DE ::= (Color).
   primitive DK ::= (Color).
   primitive FR ::= (Color).
   primitive LU ::= (Color).
   primitive NL ::= (Color).
   
   conforms := AT(at_), BE(be), CH(ch), DE(de), DK(dk), FR(fr), LU(lu), NL(nl),
   at_ != ch, at_ != de, 
   be != de, be != fr, be != lu, be != nl,
   ch != de, ch != fr,
   de != dk, de != fr, de != lu, de != nl,
   fr != lu.       
}

partial model Map of MapColoring
{
   AT(_) BE(_) CH(_) DE(_) 
   DK(_) FR(_) LU(_) NL(_)
}