--- a/src/HOL/Induct/PropLog.thy Fri Jul 24 13:03:20 1998 +0200
+++ b/src/HOL/Induct/PropLog.thy Fri Jul 24 13:19:38 1998 +0200
@@ -6,7 +6,8 @@
Inductive definition of propositional logic.
*)
-PropLog = Finite +
+PropLog = Finite + Datatype +
+
datatype
'a pl = false | var 'a ("#_" [1000]) | "->" ('a pl) ('a pl) (infixr 90)
consts
@@ -32,12 +33,12 @@
sat_def "H |= p == (!tt. (!q:H. tt[q]) --> tt[p])"
eval_def "tt[p] == eval2 p tt"
-primrec eval2 pl
+primrec
"eval2(false) = (%x. False)"
"eval2(#v) = (%tt. v:tt)"
"eval2(p->q) = (%tt. eval2 p tt-->eval2 q tt)"
-primrec hyps pl
+primrec
"hyps(false) = (%tt.{})"
"hyps(#v) = (%tt.{if v:tt then #v else #v->false})"
"hyps(p->q) = (%tt. hyps p tt Un hyps q tt)"