1.1 --- a/src/HOL/Tools/Predicate_Compile/predicate_compile_core.ML	Wed Apr 28 15:42:10 2010 +0200
     1.2 +++ b/src/HOL/Tools/Predicate_Compile/predicate_compile_core.ML	Wed Apr 28 16:45:48 2010 +0200
     1.3 @@ -531,14 +531,17 @@
     1.4        let
     1.5          val (cases, (eqs, prems)) = apsnd (chop (nargs - nparams)) (chop n prems)
     1.6          val case_th = MetaSimplifier.simplify true
     1.7 -        (@{thm Predicate.eq_is_eq} :: map meta_eq_of eqs)
     1.8 -          (nth cases (i - 1))
     1.9 +          (@{thm Predicate.eq_is_eq} :: map meta_eq_of eqs) (nth cases (i - 1))
    1.10          val prems' = maps (dest_conjunct_prem o MetaSimplifier.simplify true tuple_rew_rules) prems
    1.11          val pats = map (swap o HOLogic.dest_eq o HOLogic.dest_Trueprop) (take nargs (prems_of case_th))
    1.12          val (_, tenv) = fold (Pattern.match thy) pats (Vartab.empty, Vartab.empty)
    1.13          fun term_pair_of (ix, (ty,t)) = (Var (ix,ty), t)
    1.14          val inst = map (pairself (cterm_of thy) o term_pair_of) (Vartab.dest tenv)
    1.15 -        val thesis = Thm.instantiate ([], inst) case_th OF (replicate nargs @{thm refl}) OF prems'
    1.16 +        val case_th' = Thm.instantiate ([], inst) case_th OF (replicate nargs @{thm refl})
    1.17 +        val (_, tenv) = fold (Pattern.match thy) (prems_of case_th' ~~ map prop_of prems') (Vartab.empty, Vartab.empty)
    1.18 +        val inst' = map (pairself (cterm_of thy) o term_pair_of) (Vartab.dest tenv)
    1.19 +        val case_th'' = Thm.instantiate ([], inst') case_th'
    1.20 +        val thesis = case_th'' OF prems'
    1.21        in
    1.22          (rtac thesis 1)
    1.23        end