Email Gateway (Aug 22 2022 at 13:02): Email Gateway (Aug 22 2022 at 13:02):From: Lars Hupel <hupel@in.tum.de>
Dear BNF developers,
may I suggest theorems of the following form to be generated by the
datatype package?
theorem list_all_map:
fixes P :: "'a ⇒ bool"
and f :: "'b ⇒ 'a"
and xs :: "'b list"
shows "list_all P (map f xs) = list_all (λx. P (f x)) xs"
Cheers
Lars
Email Gateway (Aug 22 2022 at 13:02):From: Dmitriy Traytel <traytel@inf.ethz.ch>
Hi Lars,
in a recent repository version (e.g. c4fad0569a24) you get list.pred_map:
theorem
fixes Q :: "'a ⇒ bool"
and f :: "'b ⇒ 'a"
and x :: "'b list"
shows "list_all Q (map f x) = list_all (Q o f) x”
Additionally unfolding o_def will give you what you want.
Dmitriy
Last updated: Nov 21 2024 at 12:39 UTC