:: deftheorem Def1 defines commaObjs COMMACAT:def 1 :
for C, D, E being Category
for F being Functor of C,E
for G being Functor of D,E st ex c1 being Object of C ex d1 being Object of D ex f1 being Morphism of E st f1 in Hom ((F . c1),(G . d1)) holds
commaObjs (F,G) = { [[c,d],f] where c is Object of C, d is Object of D, f is Morphism of E : f in Hom ((F . c),(G . d)) } ;