Require Import HoTT. (* Lemmas from this file do not belong in this project. *) (* Some of them should probably be in the HoTT library? *) Lemma ap_inl_path_sum_inl {A B} (x y : A) (p : inl x = inl y) : ap inl (path_sum_inl B p) = p. Proof. transitivity (@path_sum _ B (inl x) (inl y) (path_sum_inl B p)); [ | apply (eisretr_path_sum _) ]. destruct (path_sum_inl B p). reflexivity. Defined. Lemma ap_equiv {A B} (f : A <~> B) {x y : A} (p : x = y) : ap (f^-1 o f) p = eissect f x @ p @ (eissect f y)^. Proof. destruct p. hott_simpl. Defined.