diff --git a/src/HOL/Sledgehammer.thy b/src/HOL/Sledgehammer.thy
--- a/src/HOL/Sledgehammer.thy
+++ b/src/HOL/Sledgehammer.thy
@@ -1,44 +1,38 @@
 (*  Title:      HOL/Sledgehammer.thy
     Author:     Lawrence C. Paulson, Cambridge University Computer Laboratory
     Author:     Jia Meng, Cambridge University Computer Laboratory and NICTA
     Author:     Jasmin Blanchette, TU Muenchen
 *)
 
 section \<open>Sledgehammer: Isabelle--ATP Linkup\<close>
 
 theory Sledgehammer
 imports Presburger SMT
 keywords
   "sledgehammer" :: diag and
   "sledgehammer_params" :: thy_decl
 begin
 
 ML_file \<open>Tools/ATP/system_on_tptp.ML\<close>
 ML_file \<open>Tools/Sledgehammer/async_manager_legacy.ML\<close>
 ML_file \<open>Tools/Sledgehammer/sledgehammer_util.ML\<close>
 ML_file \<open>Tools/Sledgehammer/sledgehammer_fact.ML\<close>
 ML_file \<open>Tools/Sledgehammer/sledgehammer_proof_methods.ML\<close>
 ML_file \<open>Tools/Sledgehammer/sledgehammer_isar_annotate.ML\<close>
 ML_file \<open>Tools/Sledgehammer/sledgehammer_isar_proof.ML\<close>
 ML_file \<open>Tools/Sledgehammer/sledgehammer_isar_preplay.ML\<close>
 ML_file \<open>Tools/Sledgehammer/sledgehammer_isar_compress.ML\<close>
 ML_file \<open>Tools/Sledgehammer/sledgehammer_isar_minimize.ML\<close>
 ML_file \<open>Tools/Sledgehammer/sledgehammer_isar.ML\<close>
 ML_file \<open>Tools/Sledgehammer/sledgehammer_atp_systems.ML\<close>
 ML_file \<open>Tools/Sledgehammer/sledgehammer_prover.ML\<close>
 ML_file \<open>Tools/Sledgehammer/sledgehammer_prover_atp.ML\<close>
 ML_file \<open>Tools/Sledgehammer/sledgehammer_prover_smt.ML\<close>
 ML_file \<open>Tools/Sledgehammer/sledgehammer_prover_minimize.ML\<close>
 ML_file \<open>Tools/Sledgehammer/sledgehammer_mepo.ML\<close>
 ML_file \<open>Tools/Sledgehammer/sledgehammer_mash.ML\<close>
 ML_file \<open>Tools/Sledgehammer/sledgehammer.ML\<close>
 ML_file \<open>Tools/Sledgehammer/sledgehammer_commands.ML\<close>
 ML_file \<open>Tools/Sledgehammer/sledgehammer_tactics.ML\<close>
 
-(*
-lemma "x - y + y = (x::nat)"
-  sledgehammer[e, abduce = 10]
-  oops
-*)
-
 end