Ng> 1. INfuNctioNal programmiNg, a BooleaN expressioN attached to a fuNctioN defiNitioN specifyiNg wheN (for what argumeNts) that defiNitioN is appropriate. 2. IN (parallel) logic programmiNg, a BooleaN expressioN which is used to select a clause from several alterNative matchiNg clauses. See Guarded HorN Clauses. 3. INparallel laNguages, a BooleaN expressioN which specifies wheN aN message may be seNt or received. (1995-05-09)