limit(Id,Year,Limit) <- course(Id,Year,Inst,Room,Limit). course(cs322,1999,david,cicsr208,120). course(cs322,1998,craig,cicsr208,100). course(cs327,1999,jim,cicsr202,50).
For example, given the knowledge base:
Then ceval(cs322,if(fun,if(easy,99,80),if(confusing,55,70)),Val) should return Val=80.prop(cs322,fun,true). prop(cs322,easy,false). prop(cs322,interesting,true). prop(cs322,confusing,true).