fact: Definition inl_injective {x y : A} : inl x = inl y -> x = y := sum_encode.
imports: Coq.Lists.List Coq.Lists.SetoidList Coq.Bool.Bool Coq.Arith.PeanoNat Coq.Strings.Ascii Coq.Strings.String Coq.Logic.Eqdep_dec Fiat.Common