Def sumdeq(a;b)(p,q)
Def == InjCase(p; pa. InjCase(q; qa. 1of(a)(pa,qa); qb. false); pb.
Def == InjCase(q; qa. false; qb. 1of(b)(pb,qb)))

is mentioned

In prior sections: mb event system 2

Try larger context: EventSystems IF YOU CAN SEE THIS go to /sfa/Nuprl/Shared/Xindentation_hack_doc.html