diff options
Diffstat (limited to 'pretyping/constr_matching.ml')
| -rw-r--r-- | pretyping/constr_matching.ml | 76 |
1 files changed, 60 insertions, 16 deletions
diff --git a/pretyping/constr_matching.ml b/pretyping/constr_matching.ml index 888c76e3d..2bc603a90 100644 --- a/pretyping/constr_matching.ml +++ b/pretyping/constr_matching.ml @@ -13,6 +13,7 @@ open Pp open CErrors open Util open Names +open Constr open Globnames open Termops open Term @@ -20,7 +21,6 @@ open EConstr open Vars open Pattern open Patternops -open Misctypes open Context.Rel.Declaration open Ltac_pretype (*i*) @@ -59,7 +59,7 @@ let warn_meta_collision = strbrk " and a metavariable of same name.") -let constrain sigma n (ids, m) (names, terms as subst) = +let constrain sigma n (ids, m) ((names,seen as names_seen), terms as subst) = let open EConstr in try let (ids', m') = Id.Map.find n terms in @@ -67,19 +67,21 @@ let constrain sigma n (ids, m) (names, terms as subst) = else raise PatternMatchingFailure with Not_found -> let () = if Id.Map.mem n names then warn_meta_collision n in - (names, Id.Map.add n (ids, m) terms) + (names_seen, Id.Map.add n (ids, m) terms) -let add_binders na1 na2 binding_vars (names, terms as subst) = +let add_binders na1 na2 binding_vars ((names,seen), terms as subst) = match na1, na2 with | Name id1, Name id2 when Id.Set.mem id1 binding_vars -> if Id.Map.mem id1 names then let () = Glob_ops.warn_variable_collision id1 in - (names, terms) + subst else + let id2 = Namegen.next_ident_away id2 seen in let names = Id.Map.add id1 id2 names in + let seen = Id.Set.add id2 seen in let () = if Id.Map.mem id1 terms then warn_meta_collision id1 in - (names, terms) + ((names,seen), terms) | _ -> subst let rec build_lambda sigma vars ctx m = match vars with @@ -183,9 +185,36 @@ let push_binder na1 na2 t ctx = Namegen.next_ident_away Namegen.default_non_dependent_ident avoid in (na1, id2, t) :: ctx -let to_fix (idx, (nas, cs, ts)) = - let inj = EConstr.of_constr in - (idx, (nas, Array.map inj cs, Array.map inj ts)) +(* This is an optimization of the main pattern-matching which shares + the longest common prefix of the body and type of a fixpoint. The + only practical effect at the time of writing is in binding variable + names: these variable names must be bound only once since the user + view at a fix displays only a (maximal) shared common prefix *) + +let rec match_under_common_fix_binders sorec sigma binding_vars ctx ctx' env env' subst t1 t2 b1 b2 = + match t1, EConstr.kind sigma t2, b1, EConstr.kind sigma b2 with + | PProd(na1,c1,t1'), Prod(na2,c2,t2'), PLambda (_,c1',b1'), Lambda (na2',c2',b2') -> + let ctx = push_binder na1 na2 c2 ctx in + let ctx' = push_binder na1 na2' c2' ctx' in + let env = EConstr.push_rel (LocalAssum (na2,c2)) env in + let subst = sorec ctx env subst c1 c2 in + let subst = sorec ctx env subst c1' c2' in + let subst = add_binders na1 na2 binding_vars subst in + match_under_common_fix_binders sorec sigma binding_vars + ctx ctx' env env' subst t1' t2' b1' b2' + | PLetIn(na1,c1,u1,t1), LetIn(na2,c2,u2,t2), PLetIn(_,c1',u1',b1), LetIn(na2',c2',u2',b2) -> + let ctx = push_binder na1 na2 u2 ctx in + let ctx' = push_binder na1 na2' u2' ctx' in + let env = EConstr.push_rel (LocalDef (na2,c2,t2)) env in + let subst = sorec ctx env subst c1 c2 in + let subst = sorec ctx env subst c1' c2' in + let subst = Option.fold_left (fun subst u1 -> sorec ctx env subst u1 u2) subst u1 in + let subst = Option.fold_left (fun subst u1' -> sorec ctx env subst u1' u2') subst u1' in + let subst = add_binders na1 na2 binding_vars subst in + match_under_common_fix_binders sorec sigma binding_vars + ctx ctx' env env' subst t1 t2 b1 b2 + | _ -> + sorec ctx' env' (sorec ctx env subst t1 t2) b1 b2 let merge_binding sigma allow_bound_rels ctx n cT subst = let c = match ctx with @@ -250,6 +279,7 @@ let matches_core env sigma allow_bound_rels | PSort ps, Sort s -> + let open Glob_term in begin match ps, ESorts.kind sigma s with | GProp, Prop Null -> subst | GSet, Prop Pos -> subst @@ -364,8 +394,20 @@ let matches_core env sigma allow_bound_rels let chk_head = sorec ctx env (sorec ctx env subst a1 a2) p1 p2 in List.fold_left chk_branch chk_head br1 - | PFix c1, Fix _ when eq_constr sigma (mkFix (to_fix c1)) cT -> subst - | PCoFix c1, CoFix _ when eq_constr sigma (mkCoFix (to_fix c1)) cT -> subst + | PFix ((ln1,i1),(lna1,tl1,bl1)), Fix ((ln2,i2),(lna2,tl2,bl2)) + when Array.equal Int.equal ln1 ln2 && i1 = i2 -> + let ctx' = Array.fold_left3 (fun ctx na1 na2 t2 -> push_binder na1 na2 t2 ctx) ctx lna1 lna2 tl2 in + let env' = Array.fold_left2 (fun env na2 c2 -> EConstr.push_rel (LocalAssum (na2,c2)) env) env lna2 tl2 in + let subst = Array.fold_left4 (match_under_common_fix_binders sorec sigma binding_vars ctx ctx' env env') subst tl1 tl2 bl1 bl2 in + Array.fold_left2 (fun subst na1 na2 -> add_binders na1 na2 binding_vars subst) subst lna1 lna2 + + | PCoFix (i1,(lna1,tl1,bl1)), CoFix (i2,(lna2,tl2,bl2)) + when i1 = i2 -> + let ctx' = Array.fold_left3 (fun ctx na1 na2 t2 -> push_binder na1 na2 t2 ctx) ctx lna1 lna2 tl2 in + let env' = Array.fold_left2 (fun env na2 c2 -> EConstr.push_rel (LocalAssum (na2,c2)) env) env lna2 tl2 in + let subst = Array.fold_left4 (match_under_common_fix_binders sorec sigma binding_vars ctx ctx' env env') subst tl1 tl2 bl1 bl2 in + Array.fold_left2 (fun subst na1 na2 -> add_binders na1 na2 binding_vars subst) subst lna1 lna2 + | PEvar (c1,args1), Evar (c2,args2) when Evar.equal c1 c2 -> Array.fold_left2 (sorec ctx env) subst args1 args2 | (PRef _ | PVar _ | PRel _ | PApp _ | PProj _ | PLambda _ @@ -373,13 +415,15 @@ let matches_core env sigma allow_bound_rels | PFix _ | PCoFix _| PEvar _), _ -> raise PatternMatchingFailure in - sorec [] env (Id.Map.empty, Id.Map.empty) pat c + sorec [] env ((Id.Map.empty,Id.Set.empty), Id.Map.empty) pat c let matches_core_closed env sigma pat c = let names, subst = matches_core env sigma false pat c in - (names, Id.Map.map snd subst) + (fst names, Id.Map.map snd subst) -let extended_matches env sigma = matches_core env sigma true +let extended_matches env sigma pat c = + let (names,_), subst = matches_core env sigma true pat c in + names, subst let matches env sigma pat c = snd (matches_core_closed env sigma (Id.Set.empty,pat) c) @@ -388,7 +432,7 @@ let special_meta = (-1) type matching_result = { m_sub : bound_ident_map * patvar_map; - m_ctx : constr; } + m_ctx : constr Lazy.t; } let mkresult s c n = IStream.Cons ( { m_sub=s; m_ctx=c; } , (IStream.thunk n) ) @@ -412,7 +456,7 @@ let authorized_occ env sigma closed pat c mk_ctx = let subst = matches_core_closed env sigma pat c in if closed && Id.Map.exists (fun _ c -> not (closed0 sigma c)) (snd subst) then (fun next -> next ()) - else (fun next -> mkresult subst (mk_ctx (mkMeta special_meta)) next) + else (fun next -> mkresult subst (lazy (mk_ctx (mkMeta special_meta))) next) with PatternMatchingFailure -> (fun next -> next ()) let subargs env v = Array.map_to_list (fun c -> (env, c)) v |