fact: Fixpoint ascend (ψ0 ψ1: valuation) (t: term) (A: stack) : term := match A with | [] => t | a :: A => ascend ψ0 ψ1 (substitute (if a then ψ1 else ψ0) t) A end.
imports: List PeanoNat Lia Relations.Relation_Operators Relations.Operators_Properties Undecidability.StackMachines(SSM) Undecidability.StackMachines.Util(CSSM_facts) Undecidability.SemiUnification.SemiU Undecidability.SemiUnification.Util(Enumerable) ssreflect ssrfun ssrbool