--- a/src/Pure/Isar/proof_context.ML Thu Mar 30 14:25:35 2000 +0200
+++ b/src/Pure/Isar/proof_context.ML Thu Mar 30 14:28:10 2000 +0200
@@ -22,6 +22,8 @@
val pretty_context: context -> Pretty.T list
val print_proof_data: theory -> unit
val init: theory -> context
+ val assumptions: context -> (cterm * ((int -> tactic) * (int -> tactic))) list
+ val fixed_names: context -> string list
val read_typ: context -> string -> typ
val cert_typ: context -> typ -> typ
val cert_skolem: context -> string -> string
@@ -38,18 +40,23 @@
val declare_term: term -> context -> context
val declare_terms: term list -> context -> context
val warn_extra_tfrees: context -> context -> context
- val add_binds: (indexname * string option) list -> context -> context
- val add_binds_i: (indexname * term option) list -> context -> context
+ val generalizeT: context -> context -> typ -> typ
+ val generalize: context -> context -> term -> term
+ val find_free: term -> string -> term option
+ val export_wrt: context -> context option
+ -> (thm -> thm) * ((int -> tactic) * (int -> tactic)) list
val auto_bind_goal: term -> context -> context
val auto_bind_facts: string -> term list -> context -> context
- val match_bind: (string list * string) list -> context -> context
- val match_bind_i: (term list * term) list -> context -> context
+ val match_bind: bool -> (string list * string) list -> context -> context
+ val match_bind_i: bool -> (term list * term) list -> context -> context
val read_propp: context * (string * (string list * string list))
-> context * (term * (term list * term list))
val cert_propp: context * (term * (term list * term list))
-> context * (term * (term list * term list))
- val bind_propp: context * (string * (string list * string list)) -> context * term
- val bind_propp_i: context * (term * (term list * term list)) -> context * term
+ val bind_propp: context * (string * (string list * string list))
+ -> context * (term * (context -> context))
+ val bind_propp_i: context * (term * (term list * term list))
+ -> context * (term * (context -> context))
val get_thm: context -> string -> thm
val get_thms: context -> string -> thm list
val get_thmss: context -> string list -> thm list
@@ -59,9 +66,6 @@
val reset_thms: string -> context -> context
val have_thmss: thm list -> string -> context attribute list
-> (thm list * context attribute list) list -> context -> context * (string * thm list)
- val assumptions: context -> (cterm * ((int -> tactic) * (int -> tactic))) list
- val fixed_names: context -> string list
- val most_general_varify_tfrees: thm -> thm
val assume: ((int -> tactic) * (int -> tactic))
-> (string * context attribute list * (string * (string list * string list)) list) list
-> context -> context * ((string * thm list) list * thm list)
@@ -107,7 +111,7 @@
defs:
typ Vartab.table * (*type constraints*)
sort Vartab.table * (*default sorts*)
- string list}; (*used type var names*)
+ (string list * term list Symtab.table)}; (*used type variables*)
exception CONTEXT of string * context;
@@ -204,7 +208,7 @@
| prems => [Pretty.big_list "prems:" (map pretty_thm prems)]);
fun pretty_context (ctxt as Context {asms = (_, (fixes, _)), cases,
- defs = (types, sorts, used), ...}) =
+ defs = (types, sorts, (used, _)), ...}) =
let
val sign = sign_of ctxt;
@@ -337,10 +341,17 @@
fun init thy =
let val data = Symtab.map (fn (_, (f, _)) => f thy) (ProofDataData.get thy) in
make_context (thy, data, (([], []), ([], [])), Vartab.empty, Symtab.empty, [],
- (Vartab.empty, Vartab.empty, []))
+ (Vartab.empty, Vartab.empty, ([], Symtab.empty)))
end;
+(* get assumptions *)
+
+fun assumptions (Context {asms = ((asms, _), _), ...}) = asms;
+fun fixed_names (Context {asms = (_, (fixes, _)), ...}) = map #2 fixes;
+fun used_table (Context {defs = (_, _, (_, tab)), ...}) = tab;
+
+
(** default sorts and types **)
@@ -349,8 +360,10 @@
fun def_type (Context {binds, defs = (types, _, _), ...}) is_pat xi =
(case Vartab.lookup (types, xi) of
None =>
- if is_pat then None
- else (case Vartab.lookup (binds, xi) of Some (Some (_, T)) => Some T | _ => None)
+ if is_pat then None else
+ (case Vartab.lookup (binds, xi) of
+ Some (Some (_, T)) => Some (TypeInfer.polymorphicT T)
+ | _ => None)
| some => some);
@@ -405,8 +418,7 @@
(* read / certify wrt. signature *) (*exception ERROR*) (*exception TERM*)
fun read_def_termTs freeze sg (types, sorts, used) sTs =
- let val (cts, env) = Thm.read_def_cterms (sg, types, sorts) used freeze sTs
- in (map Thm.term_of cts, env) end;
+ Sign.read_def_terms (sg, types, sorts) used freeze sTs;
fun read_def_termT freeze sg defs sT = apfst hd (read_def_termTs freeze sg defs [sT]);
@@ -431,6 +443,10 @@
(*beta normal form for terms (not eta normal form), chase variables in
bindings environment (code taken from Pure/envir.ML)*)
+fun unifyT ctxt (T, U) =
+ let val maxidx = Int.max (Term.maxidx_of_typ T, Term.maxidx_of_typ U)
+ in #1 (Type.unify (Sign.tsig_of (sign_of ctxt)) maxidx Vartab.empty (T, U)) end;
+
fun norm_term (ctxt as Context {binds, ...}) =
let
(*raised when norm has no effect on a term, to do sharing instead of copying*)
@@ -439,8 +455,11 @@
fun norm (t as Var (xi, T)) =
(case Vartab.lookup (binds, xi) of
Some (Some (u, U)) =>
- if T = U then (norm u handle SAME => u)
- else raise TYPE ("norm_term: ill-typed variable assigment", [T, U], [t, u])
+ let
+ val env = unifyT ctxt (T, U) handle Type.TUNIFY =>
+ raise TYPE ("norm_term: ill-typed variable assigment", [T, U], [t, u]);
+ val u' = Term.subst_TVars_Vartab env u;
+ in norm u' handle SAME => u' end
| _ => raise CONTEXT ("Unbound schematic variable: " ^ Syntax.string_of_vname xi, ctxt))
| norm (Abs (a, T, body)) = Abs (a, T, norm body)
| norm (Abs (_, _, body) $ t) = normh (subst_bound (t, body))
@@ -476,7 +495,7 @@
(* read terms *)
-fun gen_read read app is_pat (ctxt as Context {defs = (_, _, used), ...}) s =
+fun gen_read read app is_pat (ctxt as Context {defs = (_, _, (used, _)), ...}) s =
(transform_error (read (sign_of ctxt) (def_type ctxt is_pat, def_sort ctxt, used)) s
handle TERM (msg, _) => raise CONTEXT (msg, ctxt)
| ERROR_MESSAGE msg => raise CONTEXT (msg, ctxt))
@@ -496,10 +515,10 @@
(* certify terms *)
-fun gen_cert cert is_pat ctxt t =
- (cert (sign_of ctxt) t handle TERM (msg, _) => raise CONTEXT (msg, ctxt))
+fun gen_cert cert is_pat ctxt t = t
|> intern_skolem ctxt false
- |> (if is_pat then I else norm_term ctxt);
+ |> (if is_pat then I else norm_term ctxt)
+ |> (fn t' => cert (sign_of ctxt) t' handle TERM (msg, _) => raise CONTEXT (msg, ctxt));
val cert_term = gen_cert cert_term_sg false;
val cert_prop = gen_cert cert_prop_sg false;
@@ -520,9 +539,8 @@
| (sorts, TVar v) => Vartab.update (v, sorts)
| (sorts, _) => sorts));
-val ins_used = foldl_types (foldl_atyps
- (fn (used, TFree (x, _)) => x ins used
- | (used, TVar ((x, _), _)) => x ins used
+val ins_used = foldl_term_types (fn t => foldl_atyps
+ (fn ((used, tab), TFree (x, _)) => (x ins used, Symtab.update_multi ((x, t), tab))
| (used, _) => used));
fun ins_skolem def_ty = foldr
@@ -547,18 +565,113 @@
fun declare_terms ts ctxt = foldl declare (ctxt, ts);
+
+(** Hindley-Milner polymorphism **)
+
+
(* warn_extra_tfrees *)
-fun warn_extra used1 used2 =
- if used1 = used2 then ()
+local
+
+fun used_free (a, ts) =
+ (case mapfilter (fn Free (x, _) => Some x | _ => None) ts of
+ [] => None
+ | xs => Some (a, xs));
+
+fun warn_extra (names1: string list, tab1) (names2, tab2) =
+ if names1 = names2 then ()
else
- (case Library.gen_rems (op =) (used2, used1) of
- [] => ()
- | extras => warning ("DANGER!! Just introduced free type variable(s): " ^ commas (rev extras)));
+ let
+ val extra =
+ Library.gen_rems Library.eq_fst (Symtab.dest tab2, Symtab.dest tab1)
+ |> mapfilter used_free;
+ val tfrees = map #1 extra;
+ val frees = Library.sort_strings (Library.distinct (flat (map #2 extra)));
+ in
+ if null extra then ()
+ else warning ("Danger! Just introduced free type variable(s): " ^ commas tfrees ^ " in " ^
+ space_implode " or " frees)
+ end;
+
+in
fun warn_extra_tfrees (ctxt1 as Context {defs = (_, _, used1), ...})
(ctxt2 as Context {defs = (_, _, used2), ...}) = (warn_extra used1 used2; ctxt2);
+end;
+
+
+(* generalize type variables *)
+
+fun gen_tfrees inner opt_outer =
+ let
+ val inner_used = used_table inner;
+ val inner_fixes = fixed_names inner;
+ val (outer_used, outer_fixes) =
+ (case opt_outer of
+ None => (Symtab.empty, [])
+ | Some ctxt => (used_table ctxt, fixed_names ctxt));
+
+ val extra_fixes = inner_fixes \\ outer_fixes;
+ fun still_fixed (Free (x, _)) = not (x mem_string extra_fixes)
+ | still_fixed _ = false;
+
+ fun add (gen, (a, xs)) =
+ if is_some (Symtab.lookup (outer_used, a)) orelse exists still_fixed xs
+ then gen else a :: gen;
+ in Symtab.foldl add ([], inner_used) end;
+
+fun generalizeT inner outer =
+ let
+ val tfrees = gen_tfrees inner (Some outer);
+ fun gen (x, S) = if x mem_string tfrees then TVar ((x, 0), S) else TFree (x, S);
+ in Term.map_type_tfree gen end;
+
+val generalize = Term.map_term_types oo generalizeT;
+
+
+(* export theorems *)
+
+fun get_free x (None, t as Free (y, _)) = if x = y then Some t else None
+ | get_free _ (opt, _) = opt;
+
+fun find_free t x = foldl_aterms (get_free x) (None, t);
+
+
+local
+
+fun export tfrees fixes casms thm =
+ let
+ val rule =
+ thm
+ |> Drule.forall_elim_vars 0
+ |> Drule.implies_intr_list casms;
+ val {sign, prop, ...} = Thm.rep_thm rule;
+ val frees = map (Thm.cterm_of sign) (mapfilter (find_free prop) fixes);
+ in
+ rule
+ |> Drule.forall_intr_list frees
+ |> Drule.forall_elim_vars 0
+ |> Drule.tvars_intr_list tfrees
+ end;
+
+fun diff_context inner None = (gen_tfrees inner None, fixed_names inner, assumptions inner)
+ | diff_context inner (Some outer) =
+ (gen_tfrees inner (Some outer),
+ fixed_names inner \\ fixed_names outer,
+ Library.drop (length (assumptions outer), assumptions inner));
+
+in
+
+fun export_wrt inner opt_outer =
+ let
+ val (tfrees, fixes, asms) = diff_context inner opt_outer;
+ val casms = map (Drule.mk_cgoal o #1) asms;
+ val tacs = map #2 asms;
+ in (export tfrees fixes casms, tacs) end;
+
+end;
+
(** bindings **)
@@ -570,28 +683,30 @@
|> map_context (fn (thy, data, asms, binds, thms, cases, defs) =>
(thy, data, asms, Vartab.update ((xi, None), binds), thms, cases, defs));
-fun upd_bind (ctxt, (xi, t)) =
- let val T = fastype_of t in
+fun upd_bind (ctxt, ((x, i), t)) =
+ let
+ val T = Term.fastype_of t;
+ val t' =
+ if null (Term.term_tvars t \\ Term.typ_tvars T) then t
+ else Var ((x ^ "_has_extra_type_vars_on_rhs_", i), T);
+ in
ctxt
- |> declare_term t
+ |> declare_term t'
|> map_context (fn (thy, data, asms, binds, thms, cases, defs) =>
- (thy, data, asms, Vartab.update ((xi, Some (t, T)), binds), thms, cases, defs))
+ (thy, data, asms, Vartab.update (((x, i), Some (t', T)), binds), thms, cases, defs))
end;
fun del_upd_bind (ctxt, (xi, None)) = del_bind (ctxt, xi)
| del_upd_bind (ctxt, (xi, Some t)) = upd_bind (ctxt, (xi, t));
fun update_binds bs ctxt = foldl upd_bind (ctxt, bs);
-fun update_binds_env env = (*Note: Envir.norm_term ensures proper type instantiation*)
- update_binds (map (apsnd (Envir.norm_term env)) (Envir.alist_of env));
-
fun delete_update_binds bs ctxt = foldl del_upd_bind (ctxt, bs);
(* simult_matches *)
-fun simult_matches [] ctxt = ctxt
- | simult_matches pairs ctxt =
+fun simult_matches ctxt [] = []
+ | simult_matches ctxt pairs =
let
val maxidx = foldl (fn (i, (t1, t2)) =>
Int.max (i, Int.max (Term.maxidx_of_term t1, Term.maxidx_of_term t2))) (~1, pairs);
@@ -600,7 +715,10 @@
(case Seq.pull envs of
None => raise CONTEXT ("Pattern match failed!", ctxt) (* FIXME improve msg (!?) *)
| Some (env, _) => env);
- in ctxt |> update_binds_env env end;
+ val binds =
+ (*Note: Envir.norm_term ensures proper type instantiation*)
+ map (apsnd (Envir.norm_term env)) (Envir.alist_of env);
+ in binds end;
(* add_binds(_i) *)
@@ -610,13 +728,13 @@
fun gen_bind prep (ctxt, (xi as (x, _), raw_t)) =
ctxt |> delete_update_binds [(xi, apsome (prep ctxt) raw_t)];
-fun gen_binds prep binds ctxt =
- warn_extra_tfrees ctxt (foldl (gen_bind prep) (ctxt, binds));
+fun gen_binds prep binds ctxt = foldl (gen_bind prep) (ctxt, binds);
in
val add_binds = gen_binds read_term;
val add_binds_i = gen_binds cert_term;
+
val auto_bind_goal = add_binds_i o AutoBind.goal;
val auto_bind_facts = add_binds_i oo AutoBind.facts;
@@ -627,16 +745,26 @@
local
-fun gen_bind (prep, prep_pats) (ctxt, (raw_pats, raw_t)) =
+fun prep_bind (prep, prep_pats) (ctxt, (raw_pats, raw_t)) =
let
val t = prep ctxt raw_t;
val ctxt' = declare_term t ctxt;
val pats = prep_pats (fastype_of t) ctxt' raw_pats;
- val ctxt'' = ctxt' |> simult_matches (map (rpair t) pats);
- in ctxt'' end;
+ val binds = simult_matches ctxt' (map (rpair t) pats);
+ in (ctxt', binds) end;
-fun gen_binds prepp binds ctxt =
- warn_extra_tfrees ctxt (foldl (gen_bind prepp) (ctxt, binds));
+fun gen_binds prepp gen raw_binds ctxt =
+ let
+ val (ctxt', binds) = apsnd flat (foldl_map (prep_bind prepp) (ctxt, raw_binds));
+ val binds' =
+ if gen then map (apsnd (generalize ctxt' ctxt)) binds
+ else binds;
+ val binds'' = map (apsnd Some) binds';
+ in
+ warn_extra_tfrees ctxt
+ (if gen then ctxt (*sic!*) |> declare_terms (map #2 binds') |> add_binds_i binds''
+ else ctxt' |> add_binds_i binds'')
+ end;
in
@@ -664,8 +792,15 @@
fun gen_bind_propp prepp (ctxt, propp) =
let
val (ctxt', (prop, (pats1, pats2))) = prepp (ctxt, propp);
- val pairs = map (rpair prop) pats1 @ map (rpair (Logic.strip_imp_concl prop)) pats2;
- in (ctxt' |> simult_matches pairs, prop) end;
+ val pairs =
+ map (rpair prop) pats1 @
+ map (rpair (Logic.strip_imp_concl prop)) pats2; (* FIXME handle params!? *)
+ val binds = simult_matches ctxt' pairs;
+
+ (*note: context evaluated now, binds added later (lazy)*)
+ val gen = generalize ctxt' ctxt;
+ fun gen_binds ct = ct |> add_binds_i (map (apsnd (Some o gen)) binds);
+ in (ctxt' |> add_binds_i (map (apsnd Some) binds), (prop, gen_binds)) end;
val bind_propp = gen_bind_propp read_propp;
val bind_propp_i = gen_bind_propp cert_propp;
@@ -724,22 +859,8 @@
(** assumptions **)
-(* get assumptions *)
-
-fun assumptions (Context {asms = ((asms, _), _), ...}) = asms;
-fun fixed_names (Context {asms = (_, (fixes, _)), ...}) = map #2 fixes;
-
-
(* assume *)
-fun most_general_varify_tfrees thm =
- let
- val {hyps, prop, ...} = Thm.rep_thm thm;
- val frees = foldr Term.add_term_frees (prop :: hyps, []);
- val leave_tfrees = foldr Term.add_term_tfree_names (frees, []);
- in thm |> Thm.varifyT' leave_tfrees end;
-
-
local
fun gen_assm prepp tac (ctxt, (name, attrs, raw_prop_pats)) =
@@ -748,8 +869,7 @@
val cprops = map (Thm.cterm_of (sign_of ctxt')) props;
val cprops_tac = map (rpair tac) cprops;
- val asms =
- map (most_general_varify_tfrees o Drule.forall_elim_vars 0 o Drule.assume_goal) cprops;
+ val asms = map (Drule.forall_elim_vars 0 o Drule.assume_goal) cprops;
val ths = map (fn th => ([th], [])) asms;
val (ctxt'', (_, thms)) =
@@ -770,8 +890,8 @@
in
-val assume = gen_assms bind_propp;
-val assume_i = gen_assms bind_propp_i;
+val assume = gen_assms (apsnd #1 o bind_propp);
+val assume_i = gen_assms (apsnd #1 o bind_propp_i);
end;