Def  == Unit+Unit

is mentioned by

Thm* M:MsgA. ma-is-empty(M)	[ma-is-empty_wf]
Thm* M:MsgA, l:IdLnk. M sends on link l	[ma-sends-on_wf]

In prior sections: bool 1 list 1 sqequal 1 rel 1 mb nat mb list 1 mb list 2 mb event system 1 mb event system 2 mb event system 3

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