Def P  Q == (P  Q) & (P  Q)

is mentioned by

Thm* l:'a List. null(l)  mt(l)	[assert_of_null_is_mt]
Thm* l,ll:'a List. mt(l @ ll)  mt(l) & mt(ll)	[mt_append]

In prior sections: core fun 1 well fnd int 1 bool 1 int 2 list 1 hol hol bool hol num hol pair hol prim rec

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