fact: Definition MoveToSymbol_Step_Fun : tape sig -> tape sig := fun t1 => match current t1 with | Some s => if (f s) then tape_write t1 (Some (g s)) else doAct t1 (Some (g s), Rmove) | _ => t1 end.
imports: Undecidability(TM.Util.Prelim) Undecidability(TM.Basic.Mono) Undecidability(TM.Combinators.Combinators) Undecidability(TM.Compound.TMTac) Undecidability(TM.Compound.Multi) Coq(FunInd) Coq(Recdef)