provenance for Negation in Rules

[jensdietrich]

this is used in checkcast rule:

IDB_CHECKCAST(cat("R_CHECKCAST","[",factid1,"]"),methodid,instructioncounter,desc) :- 
      CHECKCAST(factid1,methodid,instructioncounter,desc), 
      !CHECKCAST(_,methodid,instructioncounter-1,desc).

Need to read paper for ideas. Will probably need updated grammar. The most obvious way is to just record that a certain predicate had been negated, but this does not capture instantiated slots.