fact: Fixpoint iter_show (ss : list showM) : showM := match ss with | nil => empty | cons s ss => cat s (iter_show ss) end.
imports: Coq.Strings.String Coq.Program.Wf Coq.PArith.BinPos Coq.ZArith.ZArith ExtLib.Structures.Monoid ExtLib.Structures.Reducible ExtLib.Programming.Injection ExtLib.Data.Char ExtLib.Data.String ExtLib.Data.Fun ExtLib.Core.RelDec