# HG changeset patch
# User wenzelm
# Date 931288110 -7200
# Node ID 9bc05ec3497b0a8ce8a0e97968954ce9fc5af71e
# Parent  4125d6b6d8f9f4e3ba12e23b028d052bedefd857
added Numeral.thy, Tools/numeral_syntax.ML;

diff -r 4125d6b6d8f9 -r 9bc05ec3497b src/HOL/IsaMakefile
--- a/src/HOL/IsaMakefile	Tue Jul 06 21:06:51 1999 +0200
+++ b/src/HOL/IsaMakefile	Tue Jul 06 21:08:30 1999 +0200
@@ -31,9 +31,9 @@
 Pure:
 	@cd $(SRC)/Pure; $(ISATOOL) make Pure
 
-$(OUT)/HOL: $(OUT)/Pure $(SRC)/Provers/Arith/cancel_sums.ML \
-  $(SRC)/Provers/Arith/fast_lin_arith.ML	\
-  $(SRC)/Provers/Arith/abel_cancel.ML $(SRC)/Provers/blast.ML \
+$(OUT)/HOL: $(OUT)/Pure $(SRC)/Provers/Arith/abel_cancel.ML \
+  $(SRC)/Provers/Arith/cancel_sums.ML		\
+  $(SRC)/Provers/Arith/fast_lin_arith.ML $(SRC)/Provers/blast.ML \
   $(SRC)/Provers/clasimp.ML $(SRC)/Provers/classical.ML \
   $(SRC)/Provers/hypsubst.ML $(SRC)/Provers/simplifier.ML \
   $(SRC)/Provers/split_paired_all.ML $(SRC)/Provers/splitter.ML \
@@ -49,18 +49,19 @@
   Integ/Equiv.thy Integ/IntDef.ML Integ/IntDef.thy Integ/Int.ML \
   Integ/Int.thy Integ/simproc.ML Lfp.ML Lfp.thy List.ML List.thy \
   Main.thy Map.ML Map.thy Nat.ML Nat.thy NatDef.ML NatDef.thy \
-  Option.ML Option.thy Ord.ML Ord.thy Power.ML Power.thy Prod.ML \
-  Prod.thy ROOT.ML Recdef.thy Record.thy RelPow.ML RelPow.thy \
+  Numeral.thy Option.ML Option.thy Ord.ML Ord.thy Power.ML Power.thy \
+  Prod.ML Prod.thy ROOT.ML Recdef.thy Record.thy RelPow.ML RelPow.thy \
   Relation.ML Relation.thy Set.ML Set.thy Sexp.ML Sexp.thy String.thy \
   Sum.ML Sum.thy Tools/datatype_aux.ML Tools/datatype_abs_proofs.ML \
   Tools/datatype_package.ML Tools/datatype_prop.ML \
   Tools/datatype_rep_proofs.ML Tools/induct_method.ML \
-  Tools/inductive_package.ML Tools/primrec_package.ML \
-  Tools/recdef_package.ML Tools/record_package.ML \
-  Tools/typedef_package.ML Trancl.ML Trancl.thy Univ.ML Univ.thy \
-  Vimage.ML Vimage.thy WF.ML WF.thy WF_Rel.ML WF_Rel.thy cladata.ML \
-  equalities.ML equalities.thy hologic.ML mono.ML mono.thy simpdata.ML \
-  subset.ML subset.thy thy_syntax.ML
+  Tools/inductive_package.ML Tools/numeral_syntax.ML \
+  Tools/primrec_package.ML Tools/recdef_package.ML \
+  Tools/record_package.ML Tools/typedef_package.ML Trancl.ML \
+  Trancl.thy Univ.ML Univ.thy Vimage.ML Vimage.thy WF.ML WF.thy \
+  WF_Rel.ML WF_Rel.thy cladata.ML equalities.ML equalities.thy \
+  hologic.ML mono.ML mono.thy simpdata.ML subset.ML subset.thy \
+  thy_syntax.ML
 	@$(ISATOOL) usedir -b $(OUT)/Pure HOL
 
 
diff -r 4125d6b6d8f9 -r 9bc05ec3497b src/HOL/Numeral.thy
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/HOL/Numeral.thy	Tue Jul 06 21:08:30 1999 +0200
@@ -0,0 +1,28 @@
+(*  Title:      HOL/Numeral.thy
+    ID:         $Id$
+    Author:     Larry Paulson and Markus Wenzel
+
+Generic numerals represented as twos-complement bitstrings.
+*)
+
+theory Numeral = Datatype
+files "Tools/numeral_syntax.ML":;
+
+datatype
+  bin = Pls
+      | Min
+      | Bit bin bool	(infixl "BIT" 90);
+
+axclass
+  numeral < "term";
+
+consts
+  number_of :: "bin => 'a::numeral";
+
+syntax
+  "_Numeral" :: "xnum => 'a"	("_");
+
+setup NumeralSyntax.setup;
+
+
+end;
diff -r 4125d6b6d8f9 -r 9bc05ec3497b src/HOL/Tools/numeral_syntax.ML
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/HOL/Tools/numeral_syntax.ML	Tue Jul 06 21:08:30 1999 +0200
@@ -0,0 +1,103 @@
+(*  Title:      HOL/Tools/numeral_syntax.ML
+    ID:         $Id$
+    Author:     Markus Wenzel, TU Muenchen
+
+Concrete syntax for generic numerals.  Assumes consts and syntax of
+theory HOL/Numeral.
+*)
+
+signature NUMERAL_SYNTAX =
+sig
+  val dest_bin: term -> int
+  val setup: (theory -> theory) list
+end;
+
+structure NumeralSyntax: NUMERAL_SYNTAX =
+struct
+
+
+(* bits *)
+
+fun mk_bit 0 = Syntax.const "False"
+  | mk_bit 1 = Syntax.const "True"
+  | mk_bit _ = sys_error "mk_bit";
+
+fun dest_bit (Const ("False", _)) = 0
+  | dest_bit (Const ("True", _)) = 1
+  | dest_bit _ = raise Match;
+
+
+(* bit strings *)   (*we try to handle superfluous leading digits nicely*)
+
+fun prefix_len _ [] = 0
+  | prefix_len pred (x :: xs) =
+      if pred x then 1 + prefix_len pred xs else 0;
+
+fun mk_bin str =
+  let
+    val (sign, digs) =
+      (case Symbol.explode str of
+        "#" :: "-" :: cs => (~1, cs)
+      | "#" :: cs => (1, cs)
+      | _ => raise ERROR);
+
+    fun bin_of 0  = []
+      | bin_of ~1 = [~1]
+      | bin_of n  = (n mod 2) :: bin_of (n div 2);
+
+    fun term_of []   = Syntax.const "Numeral.bin.Pls"
+      | term_of [~1] = Syntax.const "Numeral.bin.Min"
+      | term_of (b :: bs) = Syntax.const "Numeral.bin.Bit" $ term_of bs $ mk_bit b;
+    in term_of (bin_of (sign * (#1 (Term.read_int digs)))) end;
+
+(*we consider all "spellings"; Min is likely to be declared elsewhere*)
+fun bin_of (Const ("Pls", _)) = []
+  | bin_of (Const ("bin.Pls", _)) = []
+  | bin_of (Const ("Numeral.bin.Pls", _)) = []
+  | bin_of (Const ("Min", _)) = [~1]
+  | bin_of (Const ("bin.Min", _)) = [~1]
+  | bin_of (Const ("Numeral.bin.Min", _)) = [~1]
+  | bin_of (Const ("Bit", _) $ bs $ b) = dest_bit b :: bin_of bs
+  | bin_of (Const ("bin.Bit", _) $ bs $ b) = dest_bit b :: bin_of bs
+  | bin_of (Const ("Numeral.bin.Bit", _) $ bs $ b) = dest_bit b :: bin_of bs
+  | bin_of _ = raise Match;
+
+fun int_of [] = 0
+  | int_of (b :: bs) = b + 2 * int_of bs;
+
+val dest_bin = int_of o bin_of;
+
+fun dest_bin_str tm =
+  let
+    val rev_digs = bin_of tm;
+    val (sign, zs) =
+      (case rev rev_digs of
+        ~1 :: bs => ("-", prefix_len (equal 1) bs)
+      | bs => ("", prefix_len (equal 0) bs));
+    val num = string_of_int (abs (int_of rev_digs));
+  in "#" ^ sign ^ implode (replicate zs "0") ^ num end;
+
+
+(* translation of integer numeral tokens to and from bitstrings *)
+
+fun numeral_tr (*"_Numeral"*) [t as Free (str, _)] =
+      (Syntax.const "Numeral.number_of" $
+        (mk_bin str handle ERROR => raise TERM ("numeral_tr", [t])))
+  | numeral_tr (*"_Numeral"*) ts = raise TERM ("numeral_tr", ts);
+
+fun numeral_tr' show_sorts (*"number_of"*) (Type ("fun", [_, T])) (t :: ts) =
+      let val t' = Syntax.const "_Numeral" $ (Syntax.const "_xnum" $ Syntax.free (dest_bin_str t)) in
+        if can Term.dest_Type T then t'
+        else Syntax.const Syntax.constrainC $ t' $ Syntax.term_of_typ show_sorts T
+      end
+  | numeral_tr' _ (*"number_of"*) _ _ = raise Match;
+
+
+(* theory setup *)
+
+val setup =
+ [Theory.add_trfuns ([], [("_Numeral", numeral_tr)], [], []),
+  Theory.add_trfunsT [("number_of", numeral_tr'), ("Numeral.number_of", numeral_tr')]];
+
+
+end;