X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=helm%2FgTopLevel%2FproofEngine.ml;h=5f0ba8aaa97ee00f7c085f70386e17b5244e3484;hb=89262281b6e83bd2321150f81f1a0583645eb0c8;hp=f9250d3e3377c37723fcc4ae5744f422fdf0be4f;hpb=d1d5f6ee41209f05c072ba20e3cd50bc774ebff4;p=helm.git diff --git a/helm/gTopLevel/proofEngine.ml b/helm/gTopLevel/proofEngine.ml index f9250d3e3..5f0ba8aaa 100644 --- a/helm/gTopLevel/proofEngine.ml +++ b/helm/gTopLevel/proofEngine.ml @@ -1,96 +1,51 @@ -type binder_type = - Declaration - | Definition -;; +(* Copyright (C) 2000, HELM Team. + * + * This file is part of HELM, an Hypertextual, Electronic + * Library of Mathematics, developed at the Computer Science + * Department, University of Bologna, Italy. + * + * HELM is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * HELM is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with HELM; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, + * MA 02111-1307, USA. + * + * For details, see the HELM World-Wide-Web page, + * http://cs.unibo.it/helm/. + *) -type metas_context = (int * Cic.term) list;; +open ProofEngineHelpers +open ProofEngineTypes -type context = (binder_type * Cic.name * Cic.term) list;; + (* proof assistant status *) -type sequent = context * Cic.term;; +let proof = ref (None : proof option) +let goal = ref (None : goal option) -let proof = ref (None : (metas_context * Cic.term * Cic.term) option);; -(*CSC: Quando facciamo Clear di una ipotesi, cosa succede? *) -(* Note: the sequent is redundant: it can be computed from the type of the *) -(* metavariable and its context in the proof. We keep it just for efficiency *) -(* because computing the context of a term may be quite expensive. *) -let goal = ref (None : (int * sequent) option);; - -exception NotImplemented - -(*CSC: Funzione che deve sparire!!! *) -let cic_context_of_context = - List.map - (function - Declaration,_,t -> t - | Definition,_,_ -> raise NotImplemented - ) -;; - -let refine_meta meta term newmetasenv = - let (metasenv,bo,ty) = - match !proof with - None -> assert false - | Some (metasenv,bo,ty) -> metasenv,bo,ty - in - let metasenv' = newmetasenv @ (List.remove_assoc meta metasenv) in - let bo' = - let rec aux = - let module C = Cic in - function - C.Rel _ as t -> t - | C.Var _ as t -> t - | C.Meta meta' when meta=meta' -> term - | C.Meta _ as t -> t - | C.Sort _ as t -> t - | C.Implicit as t -> t - | C.Cast (te,ty) -> C.Cast (aux te, aux ty) - | C.Prod (n,s,t) -> C.Prod (n, aux s, aux t) - | C.Lambda (n,s,t) -> C.Lambda (n, aux s, aux t) - | C.LetIn (n,s,t) -> C.LetIn (n, aux s, aux t) - | C.Appl l -> C.Appl (List.map aux l) - | C.Const _ as t -> t - | C.Abst _ as t -> t - | C.MutInd _ as t -> t - | C.MutConstruct _ as t -> t - | C.MutCase (sp,cookingsno,i,outt,t,pl) -> - C.MutCase (sp,cookingsno,i,aux outt, aux t, - List.map aux pl) - | C.Fix (i,fl) -> - let substitutedfl = - List.map - (fun (name,i,ty,bo) -> (name, i, aux ty, aux bo)) - fl - in - C.Fix (i, substitutedfl) - | C.CoFix (i,fl) -> - let substitutedfl = - List.map - (fun (name,ty,bo) -> (name, aux ty, aux bo)) - fl - in - C.CoFix (i, substitutedfl) - in - aux bo - in - proof := Some (metasenv',bo',ty) -;; - -let new_meta () = - let metasenv = - match !proof with - None -> assert false - | Some (metasenv,_,_) -> metasenv - in - let rec aux = - function - None,[] -> 1 - | Some n,[] -> n - | None,(n,_)::tl -> aux (Some n,tl) - | Some m,(n,_)::tl -> if n > m then aux (Some n,tl) else aux (Some m,tl) - in - 1 + aux (None,metasenv) -;; +let apply_tactic ~tactic:tactic = + match !proof,!goal with + None,_ + | _,None -> assert false + | Some proof', Some goal' -> + let (newproof, newgoals) = tactic ~status:(proof', goal') in + proof := Some newproof; + goal := + (match newgoals, newproof with + goal::_, _ -> Some goal + | [], (_,(goal,_,_)::_,_,_) -> + (* the tactic left no open goal ; let's choose the first open goal *) +(*CSC: here we could implement and use a proof-tree like notion... *) + Some goal + | _, _ -> None) (* metas_in_term term *) (* Returns the ordered list of the metas that occur in [term]. *) @@ -101,7 +56,7 @@ let metas_in_term term = function C.Rel _ | C.Var _ -> [] - | C.Meta n -> [n] + | C.Meta (n,_) -> [n] | C.Sort _ | C.Implicit -> [] | C.Cast (te,ty) -> (aux te) @ (aux ty) @@ -110,7 +65,6 @@ let metas_in_term term = | C.LetIn (_,s,t) -> (aux s) @ (aux t) | C.Appl l -> List.fold_left (fun i t -> i @ (aux t)) [] l | C.Const _ - | C.Abst _ | C.MutInd _ | C.MutConstruct _ -> [] | C.MutCase (sp,cookingsno,i,outt,t,pl) -> @@ -129,7 +83,6 @@ let metas_in_term term = he::(elim_duplicates (List.filter (function el -> he <> el) tl)) in elim_duplicates metas -;; (* perforate context term ty *) (* replaces the term [term] in the proof with a new metavariable whose type *) @@ -138,121 +91,187 @@ let metas_in_term term = (* are efficiency reasons. *) let perforate context term ty = let module C = Cic in - let newmeta = new_meta () in - match !proof with - None -> assert false - | Some (metasenv,bo,gty) -> + match !proof with + None -> assert false + | Some (uri,metasenv,bo,gty as proof') -> + let newmeta = new_meta proof' in (* We push the new meta at the end of the list for pretty-printing *) (* purposes: in this way metas are ordered. *) - let metasenv' = metasenv@[newmeta,ty] in - let rec aux = - function - (* Is == strong enough? *) - t when t == term -> C.Meta newmeta - | C.Rel _ as t -> t - | C.Var _ as t -> t - | C.Meta _ as t -> t - | C.Sort _ as t -> t - | C.Implicit as t -> t - | C.Cast (te,ty) -> C.Cast (aux te, aux ty) - | C.Prod (n,s,t) -> C.Prod (n, aux s, aux t) - | C.Lambda (n,s,t) -> C.Lambda (n, aux s, aux t) - | C.LetIn (n,s,t) -> C.LetIn (n, aux s, aux t) - | C.Appl l -> C.Appl (List.map aux l) - | C.Const _ as t -> t - | C.Abst _ as t -> t - | C.MutInd _ as t -> t - | C.MutConstruct _ as t -> t - | C.MutCase (sp,cookingsno,i,outt,t,pl) -> - C.MutCase (sp,cookingsno,i,aux outt, aux t, - List.map aux pl) - | C.Fix (i,fl) -> - let substitutedfl = - List.map - (fun (name,i,ty,bo) -> (name, i, aux ty, aux bo)) - fl - in - C.Fix (i, substitutedfl) - | C.CoFix (i,fl) -> - let substitutedfl = - List.map - (fun (name,ty,bo) -> (name, aux ty, aux bo)) - fl - in - C.CoFix (i, substitutedfl) - in - let bo' = aux bo in + let metasenv' = metasenv@[newmeta,context,ty] in + let irl = identity_relocation_list_for_metavariable context in +(*CSC: Bug: se ci sono due term uguali nella prova dovrei bucarne uno solo!!!*) + let bo' = + ProofEngineReduction.replace (==) term (C.Meta (newmeta,irl)) bo + in (* It may be possible that some metavariables occurred only in *) (* the term we are perforating and they now occurs no more. We *) (* get rid of them, collecting the really useful metavariables *) (* in metasenv''. *) +(*CSC: Bug: una meta potrebbe non comparire in bo', ma comparire nel tipo *) +(*CSC: di una metavariabile che compare in bo'!!!!!!! *) let newmetas = metas_in_term bo' in let metasenv'' = - List.filter (function (n,_) -> List.mem n newmetas) metasenv' + List.filter (function (n,_,_) -> List.mem n newmetas) metasenv' in - proof := Some (metasenv'',bo',gty) ; - goal := Some (newmeta,(context,ty)) ; - newmeta -;; + proof := Some (uri,metasenv'',bo',gty) ; + goal := Some newmeta + (************************************************************) (* Some easy tactics. *) (************************************************************) -exception Fail of string;; +(*CSC: generatore di nomi? Chiedere il nome? *) +let fresh_name = + let next_fresh_index = ref 0 +in + function () -> + incr next_fresh_index ; + "fresh_name" ^ string_of_int !next_fresh_index -let intros () = - let module C = Cic in - let module R = CicReduction in - let metasenv = - match !proof with - None -> assert false - | Some (metasenv,_,_) -> metasenv - in - let (metano,context,ty) = - match !goal with - None -> assert false - | Some (metano,(context,ty)) -> metano,context,ty - in - let newmeta = new_meta () in - let rec collect_context = - function - C.Cast (te,_) -> collect_context te - | C.Prod (n,s,t) -> - let (ctx,ty,bo) = collect_context t in - ((Declaration,n,s)::ctx,ty,C.Lambda(n,s,bo)) - | C.LetIn (n,s,t) -> - let (ctx,ty,bo) = collect_context t in - ((Definition,n,s)::ctx,ty,C.LetIn(n,s,bo)) - | _ as t -> [], t, (C.Meta newmeta) +let reduction_tactic reduction_function term = + let curi,metasenv,pbo,pty = + match !proof with + None -> assert false + | Some (curi,metasenv,bo,ty) -> curi,metasenv,bo,ty + in + let metano,context,ty = + match !goal with + None -> assert false + | Some metano -> List.find (function (m,_,_) -> m=metano) metasenv + in + (* We don't know if [term] is a subterm of [ty] or a subterm of *) + (* the type of one metavariable. So we replace it everywhere. *) + (*CSC: Il vero problema e' che non sapendo dove sia il term non *) + (*CSC: sappiamo neppure quale sia il suo contesto!!!! Insomma, *) + (*CSC: e' meglio prima cercare il termine e scoprirne il *) + (*CSC: contesto, poi ridurre e infine rimpiazzare. *) + let replace context where= +(*CSC: Per il momento se la riduzione fallisce significa solamente che *) +(*CSC: siamo nel contesto errato. Metto il try, ma che schifo!!!! *) +(*CSC: Anche perche' cosi' catturo anche quelle del replace che non dovrei *) + try + let term' = reduction_function context term in + ProofEngineReduction.replace ~equality:(==) ~what:term ~with_what:term' + ~where:where + with + _ -> where + in + let ty' = replace context ty in + let context' = + List.fold_right + (fun entry context -> + match entry with + Some (name,Cic.Def t) -> + (Some (name,Cic.Def (replace context t)))::context + | Some (name,Cic.Decl t) -> + (Some (name,Cic.Decl (replace context t)))::context + | None -> None::context + ) context [] in - let revcontext',ty',bo' = collect_context ty in - let context'' = (List.rev revcontext') @ context in - refine_meta metano bo' [newmeta,ty'] ; - goal := Some (newmeta,(context'',ty')) -;; + let metasenv' = + List.map + (function + (n,_,_) when n = metano -> (metano,context',ty') + | _ as t -> t + ) metasenv + in + proof := Some (curi,metasenv',pbo,pty) ; + goal := Some metano -(* The term bo must be closed in the current context *) -let exact bo = - let module T = CicTypeChecker in - let module R = CicReduction in - let metasenv = - match !proof with - None -> assert false - | Some (metasenv,_,_) -> metasenv - in - let (metano,context,ty) = - match !goal with - None -> assert false - | Some (metano,(context,ty)) -> - assert (ty = List.assoc metano metasenv) ; - (* Invariant: context is the actual context of the meta in the proof *) - metano,context,ty - in - (*CSC: deve sparire! *) - let context = cic_context_of_context context in - if R.are_convertible (T.type_of_aux' metasenv context bo) ty then - refine_meta metano bo [] - else - raise (Fail "The type of the provided term is not the one expected.") -;; +(* Reduces [term] using [reduction_function] in the current scratch goal [ty] *) +let reduction_tactic_in_scratch reduction_function term ty = + let metasenv = + match !proof with + None -> [] + | Some (_,metasenv,_,_) -> metasenv + in + let metano,context,_ = + match !goal with + None -> assert false + | Some metano -> List.find (function (m,_,_) -> m=metano) metasenv + in + let term' = reduction_function context term in + ProofEngineReduction.replace + ~equality:(==) ~what:term ~with_what:term' ~where:ty + +let whd = reduction_tactic CicReduction.whd +let reduce = reduction_tactic ProofEngineReduction.reduce +let simpl = reduction_tactic ProofEngineReduction.simpl + +let whd_in_scratch = reduction_tactic_in_scratch CicReduction.whd +let reduce_in_scratch = + reduction_tactic_in_scratch ProofEngineReduction.reduce +let simpl_in_scratch = + reduction_tactic_in_scratch ProofEngineReduction.simpl + +(* It is just the opposite of whd. The code should probably be merged. *) +let fold term = + let curi,metasenv,pbo,pty = + match !proof with + None -> assert false + | Some (curi,metasenv,bo,ty) -> curi,metasenv,bo,ty + in + let metano,context,ty = + match !goal with + None -> assert false + | Some metano -> List.find (function (m,_,_) -> m=metano) metasenv + in + let term' = CicReduction.whd context term in + (* We don't know if [term] is a subterm of [ty] or a subterm of *) + (* the type of one metavariable. So we replace it everywhere. *) + (*CSC: ma si potrebbe ovviare al problema. Ma non credo *) + (*CSC: che si guadagni nulla in fatto di efficienza. *) + let replace = + ProofEngineReduction.replace + ~equality: + (ProofEngineReduction.syntactic_equality ~alpha_equivalence:false) + ~what:term' ~with_what:term + in + let ty' = replace ty in + let context' = + List.map + (function + Some (n,Cic.Decl t) -> Some (n,Cic.Decl (replace t)) + | Some (n,Cic.Def t) -> Some (n,Cic.Def (replace t)) + | None -> None + ) context + in + let metasenv' = + List.map + (function + (n,_,_) when n = metano -> (metano,context',ty') + | _ as t -> t + ) metasenv + in + proof := Some (curi,metasenv',pbo,pty) ; + goal := Some metano + +(************************************************************) +(* Tactics defined elsewhere *) +(************************************************************) + + (* primitive tactics *) + +let apply term = apply_tactic (PrimitiveTactics.apply_tac ~term) +let intros () = + apply_tactic (PrimitiveTactics.intros_tac ~name:(fresh_name ())) +let cut term = apply_tactic (PrimitiveTactics.cut_tac ~term) +let letin term = apply_tactic (PrimitiveTactics.letin_tac ~term) +let exact term = apply_tactic (PrimitiveTactics.exact_tac ~term) +let elim_intros_simpl term = + apply_tactic (PrimitiveTactics.elim_intros_simpl_tac ~term) +let change ~goal_input:what ~input:with_what = + apply_tactic (PrimitiveTactics.change_tac ~what ~with_what) + + (* structural tactics *) + +let clearbody hyp = apply_tactic (ProofEngineStructuralRules.clearbody ~hyp) +let clear hyp = apply_tactic (ProofEngineStructuralRules.clear ~hyp) + + (* other tactics *) + +let elim_type term = apply_tactic (Ring.elim_type_tac ~term) +let ring () = apply_tactic Ring.ring_tac +let fourier () = apply_tactic FourierR.fourier_tac +let rewrite_simpl term = apply_tactic (FourierR.rewrite_simpl_tac ~term)