neuper@37906: (* isac's rewriter neuper@37906: (c) Walther Neuper 2000 neuper@37906: *) neuper@37906: wneuper@59380: signature REWRITE = walther@59901: sig walther@59919: val calculate_: theory -> string * Eval_Def.eval_fn -> term -> (term * (string * thm)) option walther@59901: val eval__true: theory -> int -> term list -> (term * term) list -> Rule_Set.T -> term list * bool walther@59901: val eval_prog_expr: theory -> Rule_Set.T -> term -> term walther@59901: val eval_true_: theory -> Rule_Set.T -> term -> bool walther@59901: val eval_true: theory -> term list -> Rule_Set.T -> bool walther@59907: val rew_sub: theory -> int -> (term * term) list -> Rule_Def.rew_ord_ walther@59901: -> Rule_Set.T -> bool -> TermC.path -> term -> term -> term * term list * TermC.path * bool walther@59907: val rewrite_: theory -> Rule_Def.rew_ord_ -> Rule_Set.T -> bool -> thm -> walther@59901: term -> (term * term list) option walther@59907: val rewrite_inst_: theory -> Rule_Def.rew_ord_ -> Rule_Set.T -> bool walther@59901: -> (term * term) list -> thm -> term -> (term * term list) option walther@59901: val rewrite_set_: theory -> bool -> Rule_Set.T -> term -> (term * term list) option walther@59901: val rewrite_set_inst_: theory -> bool -> (term * term) list -> Rule_Set.T -> term -> (term * term list) option walther@59907: val rewrite_terms_: theory -> Rule_Def.rew_ord_ -> Rule_Set.T -> term list walther@59901: -> term -> (term * term list) option walther@59901: walther@59901: val trace_on: bool Unsynchronized.ref walther@59901: val depth: int Unsynchronized.ref walther@59901: val lim_deriv: int Unsynchronized.ref walther@59901: wneuper@59380: (* ---- for tests only: shifted from below to remove the Warning "unused" at fun.def. --------- *) wneuper@59380: (* NONE *) walther@59886: (*/-------------------------------------------------------- ! aktivate for Test_Isac BEGIN ---\* ) walther@59907: val rewrite__: theory -> int -> (term * term) list -> Rule_Def.rew_ord_ -> walther@59901: Rule_Set.T -> bool -> thm -> term -> (term * term list) option walther@59901: val rewrite__set_: theory -> int -> bool -> (term * term) list -> Rule_Set.T -> term -> (term * term list) option walther@59901: val app_rev: theory -> int -> Rule_Set.T -> term -> term * term list * bool walther@59901: val app_sub: theory -> int -> Rule_Set.T -> term -> term * term list * bool walther@59901: val trace1: int -> string -> unit walther@59886: ( *\--- ! aktivate for Test_Isac END ----------------------------------------------------------/*) walther@59901: end wneuper@59380: wneuper@59380: (**) wneuper@59380: structure Rewrite(**): REWRITE(**) = wneuper@59380: struct wneuper@59380: (**) neuper@37906: neuper@37906: exception NO_REWRITE; neuper@37906: exception STOP_REW_SUB; (*WN050820 quick and dirty*) neuper@37906: walther@59901: val trace_on = Unsynchronized.ref false; walther@59901: (* depth of recursion in traces of the rewriter, if trace_on:=true *) walther@59901: val depth = Unsynchronized.ref 99999; walther@59901: (* no of rewrites exceeding this int -> NO rewrite *) walther@59901: val lim_deriv = Unsynchronized.ref 100; walther@59901: neuper@52101: fun trace i str = walther@59901: if ! trace_on andalso i < ! depth then tracing (idt "#" i ^ str) else () neuper@52101: fun trace1 i str = walther@59901: if ! trace_on andalso i < ! depth then tracing (idt "#" (i + 1) ^ str) else () neuper@52101: neuper@37906: fun rewrite__ thy i bdv tless rls put_asm thm ct = wneuper@59381: let walther@59767: val (t', asms, _ (*lrd*), rew) = rew_sub thy i bdv tless rls put_asm ([(*root of the term*)]: TermC.path) walther@59878: (((TermC.inst_bdv bdv) o Eval.norm o #prop o Thm.rep_thm) thm) ct wneuper@59381: in if rew then SOME (t', distinct asms) else NONE end wneuper@59383: (* one rewrite (possibly conditional, ordered) EXOR exn EXOR go into subterms *) wneuper@59381: and rew_sub thy i bdv tless rls put_asm lrd r t = neuper@38022: (let wneuper@59381: val (lhs, rhs) = (HOLogic.dest_eq o HOLogic.dest_Trueprop o Logic.strip_imp_concl) r wneuper@59381: (*?alternative Unify.matchers: wneuper@59381: http://isabelle.in.tum.de/repos/isabelle/file/Isabelle2017/src/Pure/more_unify.ML*) wneuper@59381: val r' = Envir.subst_term (Pattern.match thy (lhs, t) (Vartab.empty, Vartab.empty)) r wneuper@59381: val p' = map HOLogic.dest_Trueprop ((fst o Logic.strip_prems) (Logic.count_prems r', [], r')) wneuper@59381: val t' = (snd o HOLogic.dest_eq o HOLogic.dest_Trueprop o Logic.strip_imp_concl) r' walther@59901: val _ = if ! trace_on andalso i < ! depth andalso p' <> [] walther@59870: then tracing (idt "#" (i + 1) ^ " eval asms: " ^ UnparseC.term_in_thy thy r') else () wneuper@59381: val (t'', p'') = (*conditional rewriting*) wneuper@59381: let wneuper@59381: val (simpl_p', nofalse) = eval__true thy (i + 1) p' bdv rls wneuper@59381: in wneuper@59381: if nofalse wneuper@59381: then walther@59901: (if ! trace_on andalso i < ! depth andalso p' <> [] walther@59870: then tracing (idt "#" (i + 1) ^ " asms accepted: " ^ UnparseC.terms_in_thy thy p' ^ walther@59870: " stored: " ^ UnparseC.terms_in_thy thy simpl_p') wneuper@59381: else(); wneuper@59381: (t',simpl_p')) (* uncond.rew. from above*) wneuper@59381: else walther@59901: (if ! trace_on andalso i < ! depth walther@59870: then tracing (idt "#" (i + 1) ^ " asms false: " ^ UnparseC.terms_in_thy thy p') wneuper@59381: else(); wneuper@59381: raise STOP_REW_SUB (* don't go into subterms of cond *)) wneuper@59381: end wneuper@59381: in wneuper@59389: if TermC.perm lhs rhs andalso not (tless bdv (t', t)) (*ordered rewriting*) walther@59901: then (if ! trace_on andalso i < ! depth walther@59870: then tracing (idt"#"i ^ " not: \"" ^ UnparseC.term_in_thy thy t ^ "\" > \"" ^ UnparseC.term_in_thy thy t' ^ "\"") wneuper@59381: else (); wneuper@59381: raise NO_REWRITE) wneuper@59381: else (t'', p'', [], true) wneuper@59381: end wneuper@59383: ) handle _ (*TODO Pattern.MATCH when tests are ready: ERROR 364ce4699452 *) => wneuper@59381: (case t of wneuper@59381: Const(s,T) => (Const(s,T),[],lrd,false) neuper@37906: | Free(s,T) => (Free(s,T),[],lrd,false) neuper@37906: | Var(n,T) => (Var(n,T),[],lrd,false) neuper@37906: | Bound i => (Bound i,[],lrd,false) neuper@37906: | Abs(s,T,body) => walther@59767: let val (t', asms, _ (*lrd*), rew) = rew_sub thy i bdv tless rls put_asm (lrd @ [TermC.D]) r body wneuper@59381: in (Abs(s, T, t'), asms, [], rew) end neuper@37906: | t1 $ t2 => walther@59767: let val (t2', asm2, lrd, rew2) = rew_sub thy i bdv tless rls put_asm (lrd @ [TermC.R]) r t2 wneuper@59381: in wneuper@59381: if rew2 then (t1 $ t2', asm2, lrd, true) wneuper@59381: else walther@59767: let val (t1', asm1, lrd, rew1) = rew_sub thy i bdv tless rls put_asm (lrd @ [TermC.L]) r t1 wneuper@59381: in if rew1 then (t1' $ t2, asm1, lrd, true) else (t1 $ t2,[], lrd, false) end wneuper@59381: end) wneuper@59381: and eval__true thy i asms bdv rls = (* simplify asumptions until one evaluates to false *) neuper@48760: if asms = [@{term True}] orelse asms = [] then ([], true) wneuper@59381: else (* this allows to check Rrls with prepat = ([@{term True}], pat) *) wneuper@59381: if asms = [@{term False}] then ([], false) wneuper@59381: else wneuper@59381: let wneuper@59381: fun chk indets [] = (indets, true) (*return asms<>True until false*) wneuper@59381: | chk indets (a :: asms) = wneuper@59381: (case rewrite__set_ thy (i + 1) false bdv rls a of wneuper@59381: NONE => (chk (indets @ [a]) asms) wneuper@59381: | SOME (t, a') => wneuper@59381: if t = @{term True} then (chk (indets @ a') asms) wneuper@59381: else if t = @{term False} then ([], false) wneuper@59381: (*asm false .. thm not applied ^^^; continue until False vvv*) wneuper@59381: else chk (indets @ [t] @ a') asms); wneuper@59381: in chk [] asms end walther@59851: and rewrite__set_ thy _ __ Rule_Set.Empty t = (* rewrite with a rule set *) walther@59870: error ("rewrite__set_ called with 'Erls' for '" ^ UnparseC.term_in_thy thy t ^ "'") walther@59850: | rewrite__set_ thy i _ _ (rrls as Rule_Set.Rrls _) t = (* rewrite with a 'reverse rule set' *) neuper@52101: let walther@59870: val _= trace i (" rls: " ^ Rule_Set.id rrls ^ " on: " ^ UnparseC.term_in_thy thy t) wneuper@59382: val (t', asm, rew) = app_rev thy (i + 1) rrls t neuper@52101: in if rew then SOME (t', distinct asm) else NONE end walther@59878: | rewrite__set_ thy i put_asm bdv rls ct = (* Rls, Seq containing Thms or Eval, Cal1 *) neuper@52101: let walther@59841: (* attention with cp to test/..: unbound thy, i, bdv, rls; TODO1803? pull out to rewrite__*) neuper@52101: datatype switch = Appl | Noap; walther@59841: fun rew_once _ asm ct Noap [] = (ct, asm) (* ?TODO unify with Prog_Expr.rew_once? *) neuper@52101: | rew_once ruls asm ct Appl [] = walther@59851: (case rls of Rule_Def.Repeat _ => rew_once ruls asm ct Noap ruls walther@59878: | Rule_Set.Sequence _ => (ct, asm) walther@59867: | rls => raise ERROR ("rew_once not appl. to \"" ^ Rule_Set.id rls ^ "\"")) wneuper@59381: | rew_once ruls asm ct apno (rul :: thms) = neuper@52101: case rul of wneuper@59416: Rule.Thm (thmid, thm) => walther@59841: (trace1 i (" try thm: \"" ^ thmid ^ "\""); walther@59852: case rewrite__ thy (i + 1) bdv ((snd o #rew_ord o Rule_Set.rep) rls) walther@59852: ((#erls o Rule_Set.rep) rls) put_asm thm ct of neuper@52101: NONE => rew_once ruls asm ct apno thms wneuper@59381: | SOME (ct', asm') => walther@59870: (trace1 i (" rewrites to: \"" ^ UnparseC.term_in_thy thy ct' ^ "\""); wneuper@59399: rew_once ruls (union (op =) asm asm') ct' Appl (rul :: thms))) wneuper@59399: (* once again try the same rule, e.g. associativity against "()"*) walther@59878: | Rule.Eval (cc as (op_, _)) => walther@59841: let val _= trace1 i (" try calc: \"" ^ op_ ^ "\"") wneuper@59521: val ct = TermC.uminus_to_string ct (*WN190312: superfluous?*) walther@59878: in case Eval.adhoc_thm thy cc ct of neuper@52101: NONE => rew_once ruls asm ct apno thms wneuper@59381: | SOME (_, thm') => neuper@52101: let walther@59852: val pairopt = rewrite__ thy (i + 1) bdv ((snd o #rew_ord o Rule_Set.rep) rls) walther@59852: ((#erls o Rule_Set.rep) rls) put_asm thm' ct; neuper@52101: val _ = if pairopt <> NONE then () else error ("rewrite_set_, rewrite_ \"" ^ walther@59875: ThmC.string_of_thm thm' ^ "\" " ^ UnparseC.term_in_thy thy ct ^ " = NONE") walther@59870: val _ = trace1 i (" calc. to: " ^ UnparseC.term_in_thy thy ((fst o the) pairopt)) neuper@52101: in rew_once ruls asm ((fst o the) pairopt) Appl (rul :: thms) end neuper@52101: end wneuper@59416: | Rule.Cal1 (cc as (op_, _)) => neuper@52101: let val _= trace1 i (" try cal1: " ^ op_ ^ "'"); wneuper@59389: val ct = TermC.uminus_to_string ct walther@59878: in case Eval.adhoc_thm1_ thy cc ct of neuper@52101: NONE => (ct, asm) wneuper@59381: | SOME (_, thm') => neuper@52101: let walther@59852: val pairopt = rewrite__ thy (i + 1) bdv ((snd o #rew_ord o Rule_Set.rep) rls) walther@59852: ((#erls o Rule_Set.rep) rls) put_asm thm' ct; neuper@52101: val _ = if pairopt <> NONE then () else error ("rewrite_set_, rewrite_ \"" ^ walther@59875: ThmC.string_of_thm thm' ^ "\" " ^ UnparseC.term_in_thy thy ct ^ " = NONE") walther@59870: val _ = trace1 i (" cal1. to: " ^ UnparseC.term_in_thy thy ((fst o the) pairopt)) neuper@52101: in the pairopt end neuper@52101: end wneuper@59416: | Rule.Rls_ rls' => neuper@52101: (case rewrite__set_ thy (i + 1) put_asm bdv rls' ct of neuper@52101: SOME (t', asm') => rew_once ruls (union (op =) asm asm') t' Appl thms wneuper@59381: | NONE => rew_once ruls asm ct apno thms) walther@59867: | r => raise ERROR ("rew_once not appl. to \"" ^ Rule.to_string r ^ "\""); walther@59852: val ruls = (#rules o Rule_Set.rep) rls; walther@59870: val _ = trace i (" rls: " ^ Rule_Set.id rls ^ " on: " ^ UnparseC.term_in_thy thy ct) neuper@52101: val (ct', asm') = rew_once ruls [] ct Noap ruls; neuper@52101: in if ct = ct' then NONE else SOME (ct', distinct asm') end walther@59865: (*-------------------------------------------------------------*) wneuper@59381: and app_rev thy i rrls t = (* apply an Rrls; if not applicable proceed with subterms *) neuper@52085: let (* check a (precond, pattern) of a rev-set; stops with 1st true *) wneuper@59381: fun chk_prepat _ _ [] _ = true neuper@52085: | chk_prepat thy erls prepat t = neuper@52085: let neuper@52085: fun chk (pres, pat) = neuper@52085: (let neuper@52085: val subst: Type.tyenv * Envir.tenv = neuper@52085: Pattern.match thy (pat, t) (Vartab.empty, Vartab.empty) neuper@52085: in neuper@52085: snd (eval__true thy (i + 1) (map (Envir.subst_term subst) pres) [] erls) wneuper@59381: end) handle _ (*TODO Pattern.MATCH*) => false wneuper@59381: fun scan_ _ [] = false wneuper@59398: | scan_ f (pp :: pps) = neuper@52085: if f pp then true else scan_ f pps; neuper@52085: in scan_ chk prepat end; neuper@52085: (* apply the normal_form of a rev-set *) walther@59850: fun app_rev' thy (Rule_Set.Rrls {erls, prepat, scr = Rule.Rfuns {normal_form, ...}, ...}) t = wneuper@59381: if chk_prepat thy erls prepat t then normal_form t else NONE walther@59867: | app_rev' _ r _ = raise ERROR ("app_rev' not appl. to \"" ^ Rule_Set.id r ^ "\""); neuper@52085: val opt = app_rev' thy rrls t neuper@52085: in neuper@52085: case opt of neuper@52085: SOME (t', asm) => (t', asm, true) neuper@52085: | NONE => app_sub thy i rrls t neuper@52085: end wneuper@59381: and app_sub thy i rrls t = (* apply an Rrls to subterms *) neuper@52085: case t of neuper@52085: Const (s, T) => (Const(s, T), [], false) neuper@52085: | Free (s, T) => (Free(s, T), [], false) neuper@52085: | Var (n, T) => (Var(n, T), [], false) neuper@52085: | Bound i => (Bound i, [], false) neuper@52085: | Abs (s, T, body) => neuper@37906: let val (t', asm, rew) = app_rev thy i rrls body neuper@37906: in (Abs(s, T, t'), asm, rew) end neuper@52085: | t1 $ t2 => neuper@52085: let val (t2', asm2, rew2) = app_rev thy i rrls t2 neuper@52085: in neuper@52085: if rew2 then (t1 $ t2', asm2, true) neuper@52085: else neuper@52085: let val (t1', asm1, rew1) = app_rev thy i rrls t1 neuper@52085: in if rew1 then (t1' $ t2, asm1, true) neuper@52085: else (t1 $ t2, [], false) neuper@52085: end wneuper@59381: end; neuper@37906: wneuper@59381: (* rewriting without argument [] for rew_ord; WN110603: shouldnt asm<>[] lead to false? *) neuper@37906: fun eval_true thy terms rls = (snd o (eval__true thy 1 terms [])) rls; neuper@37906: neuper@52101: (* rewriting without internal argument [] *) neuper@52101: fun rewrite_ thy rew_ord erls bool thm term = rewrite__ thy 1 [] rew_ord erls bool thm term; neuper@52101: fun rewrite_set_ thy bool rls term = rewrite__set_ thy 1 bool [] rls term; neuper@37906: wneuper@59381: (* variants of rewrite; TODO del. put_asm *) wneuper@59381: fun rewrite_inst_ thy rew_ord rls put_asm subst thm ct = wneuper@59381: rewrite__ thy 1 subst rew_ord rls put_asm thm ct; wneuper@59381: fun rewrite_set_inst_ thy put_asm subst rls ct = rewrite__set_ thy 1 put_asm subst rls ct; neuper@37906: neuper@38025: (* given a list of equalities (lhs = rhs) and a term, neuper@38025: replace all occurrences of lhs in the term with rhs; neuper@38025: thus the order or equalities matters: put variables in lhs first. *) neuper@38025: fun rewrite_terms_ thy ord erls equs t = neuper@42359: let neuper@42359: fun rew_ (t', asm') [] _ = (t', asm') neuper@42359: | rew_ (t', asm') (rules as r::rs) t = neuper@42359: let wneuper@59390: val (t'', asm'', _(*lrd*), rew) = rew_sub thy 1 [] ord erls false [] (HOLogic.Trueprop $ r) t neuper@42359: in neuper@42359: if rew neuper@42359: then rew_ (t'', asm' @ asm'') rules t'' neuper@42359: else rew_ (t', asm') rs t' neuper@42359: end walther@59861: val (t'', asm'') = rew_ (TermC.empty, []) equs t walther@59861: in if t'' = TermC.empty then NONE else SOME (t'', asm'') neuper@42359: end; neuper@37906: wneuper@59381: (* search ct for adjacent numerals and calculate them by operator isa_fn *) neuper@37906: fun calculate_ thy isa_fn ct = wneuper@59389: let val ct = TermC.uminus_to_string ct walther@59878: in case Eval.adhoc_thm thy isa_fn ct of neuper@37906: NONE => NONE wneuper@59381: | SOME (thmID, thm) => walther@59857: (let val rew = case rewrite_ thy Rewrite_Ord.dummy_ord Rule_Set.empty false thm ct of wneuper@59381: SOME (rew, _) => rew wneuper@59381: | NONE => raise ERROR "" wneuper@59381: in SOME (rew, (thmID, thm)) end) wneuper@59381: handle _ (*TODO Pattern.MATCH ?del?*)=> error ("calculate_: " ^ thmID ^ " does not rewrite") neuper@37906: end; neuper@37906: walther@59718: fun eval_prog_expr thy srls t = neuper@52139: let val rew = rewrite_set_ thy false srls t; neuper@52139: in case rew of SOME (res,_) => res | NONE => t end; neuper@37906: neuper@41928: fun eval_true_ _ _ (Const ("HOL.True",_)) = true walther@59722: | eval_true_ thy rls t = walther@59722: case rewrite_set_ thy false rls t of neuper@41928: SOME (Const ("HOL.True",_),_) => true neuper@37906: | _ => false; neuper@37906: wneuper@59380: end