2 ||M|| This file is part of HELM, an Hypertextual, Electronic
3 ||A|| Library of Mathematics, developed at the Computer Science
4 ||T|| Department, University of Bologna, Italy.
6 ||T|| HELM is free software; you can redistribute it and/or
7 ||A|| modify it under the terms of the GNU General Public License
8 \ / version 2 or (at your option) any later version.
9 \ / This software is distributed as is, NO WARRANTY.
10 V_______________________________________________________________ *)
12 (* $Id: terms.ml 9836 2009-06-05 15:33:35Z denes $ *)
14 let rec lexicograph f l1 l2 =
19 if c <> 0 then c else lexicograph f xs ys
24 module Utils (B : Orderings.Blob) = struct
25 module Subst = FoSubst;;
28 let rec eq_foterm x y =
31 | Terms.Leaf t1, Terms.Leaf t2 -> B.eq t1 t2
32 | Terms.Var i, Terms.Var j -> i = j
33 | Terms.Node l1, Terms.Node l2 -> List.for_all2 eq_foterm l1 l2
38 let rec compare_foterm x y =
40 | Terms.Leaf t1, Terms.Leaf t2 -> B.compare t1 t2
41 | Terms.Var i, Terms.Var j -> i - j
42 | Terms.Node l1, Terms.Node l2 -> lexicograph compare_foterm l1 l2
43 | Terms.Leaf _, ( Terms.Node _ | Terms.Var _ ) -> ~-1
44 | Terms.Node _, Terms.Leaf _ -> 1
45 | Terms.Node _, Terms.Var _ -> ~-1
49 let eq_literal l1 l2 =
51 | Terms.Predicate p1, Terms.Predicate p2 -> eq_foterm p1 p2
52 | Terms.Equation (l1,r1,ty1,o1), Terms.Equation (l2,r2,ty2,o2) ->
53 o1 = o2 && eq_foterm l1 l2 && eq_foterm r1 r2 && eq_foterm ty1 ty2
57 let compare_literal l1 l2 =
59 | Terms.Predicate p1, Terms.Predicate p2 -> compare_foterm p1 p2
60 | Terms.Equation (l1,r1,ty1,o1), Terms.Equation (l2,r2,ty2,o2) ->
61 let c = Pervasives.compare o1 o2 in
63 let c = compare_foterm l1 l2 in
65 let c = compare_foterm r1 r2 in
67 compare_foterm ty1 ty2
68 | Terms.Predicate _, Terms.Equation _ -> ~-1
69 | Terms.Equation _, Terms.Predicate _ -> 1
72 let eq_clause (id1,_,_,_,_) (id2,_,_,_,_) = id1 = id2
73 let compare_clause (id1,_,_,_,_) (id2,_,_,_,_) = Pervasives.compare id1 id2
75 let relocate maxvar varlist subst =
77 (fun i (maxvar, varlist, s) ->
78 maxvar+1, maxvar::varlist, Subst.build_subst i (Terms.Var maxvar) s)
79 varlist (maxvar+1, [], subst)
82 let fresh_clause maxvar (id, nlit, plit, varlist, proof) =
83 let maxvar, varlist, subst = relocate maxvar varlist Subst.id_subst in
84 let apply_subst_on_lit = function
85 | Terms.Equation (l,r,ty,o) ->
86 let l = Subst.apply_subst subst l in
87 let r = Subst.apply_subst subst r in
88 let ty = Subst.apply_subst subst ty in
89 Terms.Equation (l,r,ty,o)
90 | Terms.Predicate p ->
91 let p = Subst.apply_subst subst p in
94 let nlit = List.map (fun (l,s) -> (apply_subst_on_lit l,s)) nlit in
95 let plit = List.map (fun (l,s) -> (apply_subst_on_lit l,s)) plit in
98 | Terms.Exact t -> Terms.Exact (Subst.apply_subst subst t)
99 | Terms.Step (rule,c1,c2,dir,pos,s) ->
100 Terms.Step(rule,c1,c2,dir,pos,Subst.concat subst s)
102 (id, nlit, plit, varlist, proof), maxvar
105 (* may be moved inside the bag *)
106 let mk_clause maxvar nlit plit proofterm =
107 let foterm_to_lit (acc,literals) ty =
108 let vars = Terms.vars_of_term ~start_acc:acc ty in
110 | Terms.Node [ Terms.Leaf eq ; ty; l; r ] when B.eq B.eqP eq ->
111 let o = Order.compare_terms l r in
112 (vars,(Terms.Equation (l, r, ty, o),false)::literals)
113 | _ -> (vars,(Terms.Predicate ty,false)::literals)
115 let varlist = Terms.vars_of_term proofterm in
116 let (varlist,nlit) = List.fold_left foterm_to_lit (varlist,[]) nlit in
117 let (varlist,plit) = List.fold_left foterm_to_lit (varlist,[]) plit in
118 let proof = Terms.Exact proofterm in
119 fresh_clause maxvar (0, nlit, plit, varlist, proof)
122 let mk_passive_clause cl =
123 (Order.compute_clause_weight cl, cl)
126 let mk_passive_goal g =
127 (Order.compute_clause_weight g, g)
130 let compare_passive_clauses_weight (w1,(id1,_,_,_,_)) (w2,(id2,_,_,_,_)) =
131 if w1 = w2 then id1 - id2
135 let compare_passive_clauses_age (_,(id1,_,_,_,_)) (_,(id2,_,_,_,_)) =