ZF/domrange/domain_of_prod, domain_empty, etc: moved to equalities.ML where
they can be proved trivially using eq_cs
ZF/domrange/XXX_empty: renamed XXX_0
FOLP = IFOLP +
consts
cla :: "[p=>p]=>p"
rules
classical "(!!x.x:~P ==> f(x):P) ==> cla(f):P"
end