On Tuesday 21 December 2010 19:34:11, Felipe Almeida Lessa wrote: > > Theorem mirror_mirror : forall A (x : Tree A), mirror (mirror x) = x. > induction x; simpl; auto. > rewrite IHx1; rewrite IHx2; trivial. > Qed. Since mirror (mirror x) = x doesn't hold in Haskell, I take it that Coq doesn't allow infinite structures?