Def  == Unit+Unit

is mentioned by

Def is_pair == p:'a'b. x:'a. y:'b. (p = (mk_pair(x,y)))

[his_pair]

In prior sections: bool 1 hol hol bool hol min

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