It appears that the code generator (Stefan's) needs some laws that appear superfluous: {..n} = set ...
(* Title: HOL/Main.thy
ID: $Id$
*)
header {* Main HOL *}
theory Main
imports Plain Map Presburger Recdef
begin
ML {* val HOL_proofs = ! Proofterm.proofs *}
text {* See further \cite{Nipkow-et-al:2002:tutorial} *}
end