UNDISCH_ALLDrule.UNDISCH_ALL : thm -> thm
Iteratively undischarges antecedents in a chain of implications.
A |- t1 ==> ... ==> tn ==> t
------------------------------ UNDISCH_ALL
A, t1, ..., tn |- t
Note that UNDISCH_ALL treats "~u" as
"u ==> F".
UNDISCH_ALL never fails. When called on something other
than an implication or negation, it simply returns its argument
unchanged.
Identical or alpha-equivalent terms which are repeated in
A, "t1", ..., "tn" will not be duplicated in the hypotheses
of the resulting theorem.
Thm.DISCH, Drule.DISCH_ALL, Tactic.DISCH_TAC, Thm_cont.DISCH_THEN, Drule.NEG_DISCH, Tactic.FILTER_DISCH_TAC,
Tactic.FILTER_DISCH_THEN,
Tactic.STRIP_TAC, Drule.UNDISCH, Tactic.UNDISCH_TAC