--- a/src/HOL/Library/Eval.thy Wed Sep 17 07:32:04 2008 +0200
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,295 +0,0 @@
-(* Title: HOL/Library/Eval.thy
- ID: $Id$
- Author: Florian Haftmann, TU Muenchen
-*)
-
-header {* A simple term evaluation mechanism *}
-
-theory Eval
-imports
- Plain
- RType
- Code_Index (* this theory is just imported for a term_of setup *)
-begin
-
-subsection {* Term representation *}
-
-subsubsection {* Terms and class @{text term_of} *}
-
-datatype "term" = dummy_term
-
-definition
- Const :: "message_string \<Rightarrow> rtype \<Rightarrow> term"
-where
- "Const _ _ = dummy_term"
-
-definition
- App :: "term \<Rightarrow> term \<Rightarrow> term"
-where
- "App _ _ = dummy_term"
-
-code_datatype Const App
-
-class term_of = rtype +
- fixes term_of :: "'a \<Rightarrow> term"
-
-lemma term_of_anything: "term_of x \<equiv> t"
- by (rule eq_reflection) (cases "term_of x", cases t, simp)
-
-ML {*
-structure Eval =
-struct
-
-fun mk_term f g (Const (c, ty)) =
- @{term Const} $ Message_String.mk c $ g ty
- | mk_term f g (t1 $ t2) =
- @{term App} $ mk_term f g t1 $ mk_term f g t2
- | mk_term f g (Free v) = f v
- | mk_term f g (Bound i) = Bound i
- | mk_term f g (Abs (v, _, t)) = Abs (v, @{typ term}, mk_term f g t);
-
-fun mk_term_of ty t = Const (@{const_name term_of}, ty --> @{typ term}) $ t;
-
-end;
-*}
-
-
-subsubsection {* @{text term_of} instances *}
-
-setup {*
-let
- fun add_term_of_def ty vs tyco thy =
- let
- val lhs = Const (@{const_name term_of}, ty --> @{typ term})
- $ Free ("x", ty);
- val rhs = @{term "undefined \<Colon> term"};
- val eq = HOLogic.mk_Trueprop (HOLogic.mk_eq (lhs, rhs));
- in
- thy
- |> TheoryTarget.instantiation ([tyco], vs, @{sort term_of})
- |> `(fn lthy => Syntax.check_term lthy eq)
- |-> (fn eq => Specification.definition (NONE, (Attrib.no_binding, eq)))
- |> snd
- |> Class.prove_instantiation_instance (K (Class.intro_classes_tac []))
- |> LocalTheory.exit
- |> ProofContext.theory_of
- end;
- fun interpretator (tyco, (raw_vs, _)) thy =
- let
- val has_inst = can (Sorts.mg_domain (Sign.classes_of thy) tyco) @{sort term_of};
- val constrain_sort =
- curry (Sorts.inter_sort (Sign.classes_of thy)) @{sort term_of};
- val vs = (map o apsnd) constrain_sort raw_vs;
- val ty = Type (tyco, map TFree vs);
- in
- thy
- |> RType.perhaps_add_def tyco
- |> not has_inst ? add_term_of_def ty vs tyco
- end;
-in
- Code.type_interpretation interpretator
-end
-*}
-
-setup {*
-let
- fun mk_term_of_eq ty vs tyco (c, tys) =
- let
- val t = list_comb (Const (c, tys ---> ty),
- map Free (Name.names Name.context "a" tys));
- in (map_aterms (fn Free (v, ty) => Var ((v, 0), ty) | t => t) t, Eval.mk_term
- (fn (v, ty) => Eval.mk_term_of ty (Var ((v, 0), ty)))
- (RType.mk (fn (v, sort) => RType.rtype (TFree (v, sort)))) t)
- end;
- fun prove_term_of_eq ty eq thy =
- let
- val cty = Thm.ctyp_of thy ty;
- val (arg, rhs) = pairself (Thm.cterm_of thy) eq;
- val thm = @{thm term_of_anything}
- |> Drule.instantiate' [SOME cty] [SOME arg, SOME rhs]
- |> Thm.varifyT;
- in
- thy
- |> Code.add_func thm
- end;
- fun interpretator (tyco, (raw_vs, raw_cs)) thy =
- let
- val constrain_sort =
- curry (Sorts.inter_sort (Sign.classes_of thy)) @{sort term_of};
- val vs = (map o apsnd) constrain_sort raw_vs;
- val cs = (map o apsnd o map o map_atyps)
- (fn TFree (v, sort) => TFree (v, constrain_sort sort)) raw_cs;
- val ty = Type (tyco, map TFree vs);
- val eqs = map (mk_term_of_eq ty vs tyco) cs;
- val const = AxClass.param_of_inst thy (@{const_name term_of}, tyco);
- in
- thy
- |> Code.del_funcs const
- |> fold (prove_term_of_eq ty) eqs
- end;
-in
- Code.type_interpretation interpretator
-end
-*}
-
-
-subsubsection {* Code generator setup *}
-
-lemmas [code func del] = term.recs term.cases term.size
-lemma [code func, code func del]: "(t1\<Colon>term) = t2 \<longleftrightarrow> t1 = t2" ..
-
-lemma [code func, code func del]: "(term_of \<Colon> rtype \<Rightarrow> term) = term_of" ..
-lemma [code func, code func del]: "(term_of \<Colon> term \<Rightarrow> term) = term_of" ..
-lemma [code func, code func del]: "(term_of \<Colon> index \<Rightarrow> term) = term_of" ..
-lemma [code func, code func del]: "(term_of \<Colon> message_string \<Rightarrow> term) = term_of" ..
-
-code_type "term"
- (SML "Term.term")
-
-code_const Const and App
- (SML "Term.Const/ (_, _)" and "Term.$/ (_, _)")
-
-code_const "term_of \<Colon> index \<Rightarrow> term"
- (SML "HOLogic.mk'_number/ HOLogic.indexT")
-
-code_const "term_of \<Colon> message_string \<Rightarrow> term"
- (SML "Message'_String.mk")
-
-
-subsubsection {* Syntax *}
-
-print_translation {*
-let
- val term = Const ("<TERM>", dummyT);
- fun tr1' [_, _] = term;
- fun tr2' [] = term;
-in
- [(@{const_syntax Const}, tr1'),
- (@{const_syntax App}, tr1'),
- (@{const_syntax dummy_term}, tr2')]
-end
-*}
-setup {*
- Sign.declare_const [] ((Name.binding "rterm_of", @{typ "'a \<Rightarrow> 'b"}), NoSyn)
- #> snd
-*}
-
-notation (output)
- rterm_of ("\<guillemotleft>_\<guillemotright>")
-
-locale rterm_syntax =
- fixes rterm_of_syntax :: "'a \<Rightarrow> 'b" ("\<guillemotleft>_\<guillemotright>")
-
-parse_translation {*
-let
- fun rterm_of_tr [t] = Lexicon.const @{const_name rterm_of} $ t
- | rterm_of_tr ts = raise TERM ("rterm_of_tr", ts);
-in
- [(Syntax.fixedN ^ "rterm_of_syntax", rterm_of_tr)]
-end
-*}
-
-setup {*
-let
- val subst_rterm_of = Eval.mk_term
- (fn (v, _) => error ("illegal free variable in term quotation: " ^ quote v))
- (RType.mk (fn (v, sort) => RType.rtype (TFree (v, sort))));
- fun subst_rterm_of' (Const (@{const_name rterm_of}, _), [t]) = subst_rterm_of t
- | subst_rterm_of' (Const (@{const_name rterm_of}, _), _) =
- error ("illegal number of arguments for " ^ quote @{const_name rterm_of})
- | subst_rterm_of' (t, ts) = list_comb (t, map (subst_rterm_of' o strip_comb) ts);
- fun subst_rterm_of'' t =
- let
- val t' = subst_rterm_of' (strip_comb t);
- in if t aconv t'
- then NONE
- else SOME t'
- end;
- fun check_rterm_of ts ctxt =
- let
- val ts' = map subst_rterm_of'' ts;
- in if exists is_some ts'
- then SOME (map2 the_default ts ts', ctxt)
- else NONE
- end;
-in
- Context.theory_map (Syntax.add_term_check 0 "rterm_of" check_rterm_of)
-end;
-*}
-
-hide const dummy_term
-hide (open) const Const App
-hide (open) const term_of
-
-
-subsection {* Evaluation setup *}
-
-ML {*
-signature EVAL =
-sig
- val mk_term: ((string * typ) -> term) -> (typ -> term) -> term -> term
- val eval_ref: (unit -> term) option ref
- val eval_term: theory -> term -> term
- val evaluate: Proof.context -> term -> unit
- val evaluate': string -> Proof.context -> term -> unit
- val evaluate_cmd: string option -> string -> Toplevel.state -> unit
-end;
-
-structure Eval : EVAL =
-struct
-
-open Eval;
-
-val eval_ref = ref (NONE : (unit -> term) option);
-
-fun eval_term thy t =
- t
- |> Eval.mk_term_of (fastype_of t)
- |> (fn t => Code_ML.eval_term ("Eval.eval_ref", eval_ref) thy t [])
- |> Code.postprocess_term thy;
-
-val evaluators = [
- ("code", eval_term),
- ("SML", Codegen.eval_term),
- ("normal_form", Nbe.norm_term)
-];
-
-fun gen_evaluate evaluators ctxt t =
- let
- val thy = ProofContext.theory_of ctxt;
- val (evls, evl) = split_last evaluators;
- val t' = case get_first (fn f => try (f thy) t) evls
- of SOME t' => t'
- | NONE => evl thy t;
- val ty' = Term.type_of t';
- val p = Pretty.block [Pretty.quote (Syntax.pretty_term ctxt t'),
- Pretty.fbrk, Pretty.str "::", Pretty.brk 1,
- Pretty.quote (Syntax.pretty_typ ctxt ty')];
- in Pretty.writeln p end;
-
-val evaluate = gen_evaluate (map snd evaluators);
-
-fun evaluate' name = gen_evaluate
- [(the o AList.lookup (op =) evaluators) name];
-
-fun evaluate_cmd some_name raw_t state =
- let
- val ctxt = Toplevel.context_of state;
- val t = Syntax.read_term ctxt raw_t;
- in case some_name
- of NONE => evaluate ctxt t
- | SOME name => evaluate' name ctxt t
- end;
-
-end;
-*}
-
-ML {*
- OuterSyntax.improper_command "value" "read, evaluate and print term" OuterKeyword.diag
- (Scan.option (OuterParse.$$$ "(" |-- OuterParse.name --| OuterParse.$$$ ")")
- -- OuterParse.term
- >> (fn (some_name, t) => Toplevel.no_timing o Toplevel.keep
- (Eval.evaluate_cmd some_name t)));
-*}
-
-end