dest_forallboolSyntax.dest_forall : term -> term * term
Breaks apart a universally quantified term into quantified variable and body.
If M has the form !x. t, then
dest_forall M returns (x,t).
Fails if M is not a universal quantification.
boolSyntax.mk_forall,
boolSyntax.is_forall,
boolSyntax.strip_forall,
boolSyntax.list_mk_forall