# HG changeset patch
# User wenzelm
# Date 1131550015 -3600
# Node ID 691c64d615a5f82d7653ea855352b22045943d4b
# Parent  b15981aedb7b3196b7238e61bef66855a51fea7f
Explicit data structures for some Isar language elements.

diff -r b15981aedb7b -r 691c64d615a5 src/Pure/Isar/element.ML
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/Pure/Isar/element.ML	Wed Nov 09 16:26:55 2005 +0100
@@ -0,0 +1,257 @@
+(*  Title:      Pure/Isar/element.ML
+    ID:         $Id$
+    Author:     Makarius
+
+Explicit data structures for some Isar language elements.
+*)
+
+signature ELEMENT =
+sig
+  datatype ('typ, 'term, 'fact) ctxt =
+    Fixes of (string * 'typ option * mixfix option) list |
+    Constrains of (string * 'typ) list |
+    Assumes of ((string * Attrib.src list) * ('term * ('term list * 'term list)) list) list |
+    Defines of ((string * Attrib.src list) * ('term * 'term list)) list |
+    Notes of ((string * Attrib.src list) * ('fact * Attrib.src list) list) list
+  type context (*= (string, string, thmref) ctxt*)
+  type context_i (*= (typ, term, thm list) ctxt*)
+  val map_ctxt: {name: string -> string,
+    var: string * mixfix option -> string * mixfix option,
+    typ: 'typ -> 'a, term: 'term -> 'b, fact: 'fact -> 'c,
+    attrib: Attrib.src -> Attrib.src} -> ('typ, 'term, 'fact) ctxt -> ('a, 'b, 'c) ctxt
+  val map_ctxt_values: (typ -> typ) -> (term -> term) -> (thm -> thm) -> context_i -> context_i
+  val pretty_ctxt: ProofContext.context -> context_i -> Pretty.T list
+  val rename: (string * (string * mixfix option)) list -> string -> string
+  val rename_var: (string * (string * mixfix option)) list ->
+   string * mixfix option -> string * mixfix option
+  val rename_term: (string * (string * mixfix option)) list -> term -> term
+  val rename_thm: (string * (string * mixfix option)) list -> thm -> thm
+  val rename_ctxt: (string * (string * mixfix option)) list -> context_i -> context_i
+  val instT_type: typ Symtab.table -> typ -> typ
+  val instT_term: typ Symtab.table -> term -> term
+  val instT_thm: theory -> typ Symtab.table -> thm -> thm
+  val instT_ctxt: theory -> typ Symtab.table -> context_i -> context_i
+  val inst_term: typ Symtab.table * term Symtab.table -> term -> term
+  val inst_thm: theory -> typ Symtab.table * term Symtab.table -> thm -> thm
+  val inst_ctxt: theory -> typ Symtab.table * term Symtab.table -> context_i -> context_i
+end;
+
+structure Element: ELEMENT =
+struct
+
+(** context elements **)
+
+(* datatype ctxt *)
+
+datatype ('typ, 'term, 'fact) ctxt =
+  Fixes of (string * 'typ option * mixfix option) list |
+  Constrains of (string * 'typ) list |
+  Assumes of ((string * Attrib.src list) * ('term * ('term list * 'term list)) list) list |
+  Defines of ((string * Attrib.src list) * ('term * 'term list)) list |
+  Notes of ((string * Attrib.src list) * ('fact * Attrib.src list) list) list;
+
+type context = (string, string, thmref) ctxt;
+type context_i = (typ, term, thm list) ctxt;
+
+fun map_ctxt {name, var, typ, term, fact, attrib} =
+  fn Fixes fixes => Fixes (fixes |> map (fn (x, T, mx) =>
+       let val (x', mx') = var (x, mx) in (x', Option.map typ T, mx') end))
+   | Constrains xs => Constrains (xs |> map (fn (x, T) =>
+       (#1 (var (x, SOME Syntax.NoSyn)), typ T)))
+   | Assumes asms => Assumes (asms |> map (fn ((a, atts), propps) =>
+      ((name a, map attrib atts), propps |> map (fn (t, (ps, qs)) =>
+        (term t, (map term ps, map term qs))))))
+   | Defines defs => Defines (defs |> map (fn ((a, atts), (t, ps)) =>
+      ((name a, map attrib atts), (term t, map term ps))))
+   | Notes facts => Notes (facts |> map (fn ((a, atts), bs) =>
+      ((name a, map attrib atts), bs |> map (fn (ths, btts) => (fact ths, map attrib btts)))));
+
+fun map_ctxt_values typ term thm = map_ctxt
+  {name = I, var = I, typ = typ, term = term, fact = map thm,
+    attrib = Args.map_values I typ term thm};
+
+
+(* pretty_ctxt *)
+
+fun pretty_ctxt ctxt =
+  let
+    val prt_typ = Pretty.quote o ProofContext.pretty_typ ctxt;
+    val prt_term = Pretty.quote o ProofContext.pretty_term ctxt;
+    val prt_thm = Pretty.quote o ProofContext.pretty_thm ctxt;
+    val prt_atts = Args.pretty_attribs ctxt;
+
+    fun prt_syn syn =
+      let val s = (case syn of NONE => "(structure)" | SOME mx => Syntax.string_of_mixfix mx)
+      in if s = "" then [] else [Pretty.brk 2, Pretty.str s] end;
+    fun prt_fix (x, SOME T, syn) = Pretty.block (Pretty.str (x ^ " ::") :: Pretty.brk 1 ::
+          prt_typ T :: Pretty.brk 1 :: prt_syn syn)
+      | prt_fix (x, NONE, syn) = Pretty.block (Pretty.str x :: Pretty.brk 1 :: prt_syn syn);
+    fun prt_constrain (x, T) = prt_fix (x, SOME T, SOME (Syntax.NoSyn));
+
+    fun prt_name name = Pretty.str (ProofContext.extern_thm ctxt name);
+    fun prt_name_atts (name, atts) =
+      if name = "" andalso null atts then []
+      else [Pretty.block (Pretty.breaks (prt_name name :: prt_atts atts @ [Pretty.str ":"]))];
+
+    fun prt_asm (a, ts) =
+      Pretty.block (Pretty.breaks (prt_name_atts a @ map (prt_term o fst) ts));
+    fun prt_def (a, (t, _)) =
+      Pretty.block (Pretty.breaks (prt_name_atts a @ [prt_term t]));
+
+    fun prt_fact (ths, []) = map prt_thm ths
+      | prt_fact (ths, atts) =
+          Pretty.enclose "(" ")" (Pretty.breaks (map prt_thm ths)) :: prt_atts atts;
+    fun prt_note (a, ths) =
+      Pretty.block (Pretty.breaks (List.concat (prt_name_atts a :: map prt_fact ths)));
+
+    fun items _ [] = []
+      | items prfx (x :: xs) =
+          Pretty.block [Pretty.str prfx, Pretty.brk 1, x] :: items "  and" xs;
+  in
+    fn Fixes fixes => items "fixes" (map prt_fix fixes)
+     | Constrains xs => items "constrains" (map prt_constrain xs)
+     | Assumes asms => items "assumes" (map prt_asm asms)
+     | Defines defs => items "defines" (map prt_def defs)
+     | Notes facts => items "notes" (map prt_note facts)
+  end;
+
+
+
+(** logical operations **)
+
+(* derived rules *)
+
+fun instantiate_tfrees thy subst =
+  let
+    val certT = Thm.ctyp_of thy;
+    fun inst vs (a, T) = AList.lookup (op =) vs a
+      |> Option.map (fn v => (certT (TVar v), certT T));
+  in
+    Drule.tvars_intr_list (map fst subst) #->
+    (fn vs => Thm.instantiate (List.mapPartial (inst vs) subst, []))
+  end;
+
+fun instantiate_frees thy subst =
+  let val cert = Thm.cterm_of thy in
+    Drule.forall_intr_list (map (cert o Free o fst) subst) #>
+    Drule.forall_elim_list (map (cert o snd) subst)
+  end;
+
+fun hyps_rule rule th =
+  let
+    val cterm_rule = Thm.reflexive #> rule #> Thm.cprop_of #> Drule.dest_equals #> #1;
+    val {hyps, ...} = Thm.crep_thm th;
+  in
+    Drule.implies_elim_list
+      (rule (Drule.implies_intr_list hyps th))
+      (map (Thm.assume o cterm_rule) hyps)
+  end;
+
+
+(* renaming *)
+
+fun rename ren x =
+  (case AList.lookup (op =) ren (x: string) of
+    NONE => x
+  | SOME (x', _) => x');
+
+fun rename_var ren (x, mx) =
+  (case (AList.lookup (op =) ren (x: string), is_some mx) of
+    (NONE, _) => (x, mx)
+  | (SOME (x', NONE), true) => (x', SOME Syntax.NoSyn)
+  | (SOME (x', NONE), false) => (x', mx)
+  | (SOME (x', SOME mx'), true) => (x', SOME mx')
+  | (SOME (x', SOME _), false) =>
+      error ("Attempt to change syntax of structure parameter " ^ quote x));
+
+fun rename_term ren (Free (x, T)) = Free (rename ren x, T)
+  | rename_term ren (t $ u) = rename_term ren t $ rename_term ren u
+  | rename_term ren (Abs (x, T, t)) = Abs (x, T, rename_term ren t)
+  | rename_term _ a = a;
+
+fun rename_thm ren th =
+  let
+    val subst = Drule.frees_of th
+      |> List.mapPartial (fn (x, T) =>
+        let val x' = rename ren x
+        in if x = x' then NONE else SOME ((x, T), (Free (x', T))) end);
+  in
+    if null subst then th
+    else th |> hyps_rule (instantiate_frees (Thm.theory_of_thm th) subst)
+  end;
+
+fun rename_ctxt ren =
+  map_ctxt_values I (rename_term ren) (rename_thm ren)
+  #> map_ctxt {name = I, typ = I, term = I, fact = I, attrib = I, var = rename_var ren};
+
+
+(* type instantiation *)
+
+fun instT_type env =
+  if Symtab.is_empty env then I
+  else Term.map_type_tfree (fn (x, S) => the_default (TFree (x, S)) (Symtab.lookup env x));
+
+fun instT_term env =
+  if Symtab.is_empty env then I
+  else Term.map_term_types (instT_type env);
+
+fun instT_subst env th =
+  Drule.tfrees_of th
+  |> List.mapPartial (fn (a, S) =>
+    let
+      val T = TFree (a, S);
+      val T' = the_default T (Symtab.lookup env a);
+    in if T = T' then NONE else SOME (a, T') end);
+
+fun instT_thm thy env th =
+  if Symtab.is_empty env then th
+  else
+    let val subst = instT_subst env th
+    in if null subst then th else th |> hyps_rule (instantiate_tfrees thy subst) end;
+
+fun instT_ctxt thy env =
+  map_ctxt_values (instT_type env) (instT_term env) (instT_thm thy env);
+
+
+(* type and term instantiation *)
+
+fun inst_term (envT, env) =
+  if Symtab.is_empty env then instT_term envT
+  else
+    let
+      val instT = instT_type envT;
+      fun inst (Const (x, T)) = Const (x, instT T)
+        | inst (Free (x, T)) =
+            (case Symtab.lookup env x of
+              NONE => Free (x, instT T)
+            | SOME t => t)
+        | inst (Var (xi, T)) = Var (xi, instT T)
+        | inst (b as Bound _) = b
+        | inst (Abs (x, T, t)) = Abs (x, instT T, inst t)
+        | inst (t $ u) = inst t $ inst u;
+    in Envir.beta_norm o inst end;
+
+fun inst_thm thy (envT, env) th =
+  if Symtab.is_empty env then instT_thm thy envT th
+  else
+    let
+      val substT = instT_subst envT th;
+      val subst = Drule.frees_of th
+        |> List.mapPartial (fn (x, T) =>
+          let
+            val T' = instT_type envT T;
+            val t = Free (x, T');
+            val t' = the_default t (Symtab.lookup env x);
+          in if t aconv t' then NONE else SOME ((x, T'), t') end);
+    in
+      if null substT andalso null subst then th
+      else th |> hyps_rule
+       (instantiate_tfrees thy substT #>
+        instantiate_frees thy subst #>
+        Drule.fconv_rule (Thm.beta_conversion true))
+    end;
+
+fun inst_ctxt thy envs =
+  map_ctxt_values (instT_type (#1 envs)) (inst_term envs) (inst_thm thy envs);
+
+end;