diff -r 2dc8d6d262f4 -r 740ebee5948b src/Tools/isac/Interpret/derive.sml
--- a/src/Tools/isac/Interpret/derive.sml	Sun Apr 18 22:27:43 2021 +0200
+++ b/src/Tools/isac/Interpret/derive.sml	Sun Apr 18 23:37:59 2021 +0200
@@ -21,13 +21,11 @@
   val steps : Rule_Def.rew_ord -> Rule_Set.T -> Rule.rule list -> term -> term ->
     bool * derivation
   val embed: State_Steps.T -> Calc.T -> Pos.pos' list * Calc.T
-(* ---- for tests only: shifted from below to remove the Warning "unused" at fun.def. --------- *)
-  (*  NONE *)
-(*/-------------------------------------------------------- ! aktivate for Test_Isac BEGIN ---\* )
+\<^isac_test>\<open>
   val trtas2str : (term * Rule.rule * (term * term list)) list -> string
   val deriv2str : (term * Rule.rule * (term * term list)) list -> string
   val rev_deriv' : 'a * Rule.rule * ('b * 'c) -> 'b * Rule.rule * ('a * 'c)
-( *\--- ! aktivate for Test_Isac END ----------------------------------------------------------/*)
+\<close>
 end
 
 (**)