1 (* Copyright (C) 2003-2005, HELM Team.
3 * This file is part of HELM, an Hypertextual, Electronic
4 * Library of Mathematics, developed at the Computer Science
5 * Department, University of Bologna, Italy.
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15 * GNU General Public License for more details.
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23 * http://cs.unibo.it/helm/.
28 module S = CicSubstitution
29 module R = CicReduction
30 module TC = CicTypeChecker
31 module DTI = DoubleTypeInference
34 (* helper functions *********************************************************)
38 let comp f g x = f (g x)
41 let ty, _ = TC.type_of_aux' [] c t Un.empty_ugraph in ty
44 match (get_type c (get_type c t)) with
45 | C.Sort C.Prop -> true
48 let is_not_atomic = function
54 | C.MutConstruct _ -> false
58 let add s v c = Some (s, C.Decl v) :: c in
59 let rec aux whd a n c = function
60 | C.Prod (s, v, t) -> aux false (v :: a) (succ n) (add s v c) t
61 | v when whd -> v :: a, n
62 | v -> aux true a n c (R.whd ~delta:true c v)
66 let add g htbl t proof decurry =
67 if proof then C.CicHash.add htbl t decurry;
72 let decurry = C.CicHash.find htbl t in g t true decurry
73 with Not_found -> g t false 0
75 (* term preprocessing *******************************************************)
77 let expanded_premise = "EXPANDED"
79 let defined_premise = "DEFINED"
82 let ty = C.Implicit None in
83 let name i = Printf.sprintf "%s%u" expanded_premise i in
84 let lambda i t = C.Lambda (C.Name (name i), ty, t) in
85 let arg i n = C.Rel (n - i) in
87 if i >= n then f, a else aux (succ i) (comp f (lambda i)) (arg i n :: a)
89 let absts, args = aux 0 identity [] in
90 absts (C.Appl (S.lift n t :: args))
92 let eta_fix t proof decurry =
93 if proof && decurry > 0 then eta_expand decurry t else t
95 let rec pp_cast g ht es c t v =
96 if es then pp_proof g ht es c t else find g ht t
98 and pp_lambda g ht es c name v t =
99 let name = if DTI.does_not_occur 1 t then C.Anonymous else name in
100 let entry = Some (name, C.Decl v) in
102 let t = eta_fix t true decurry in
103 g (C.Lambda (name, v, t)) true 0 in
104 if es then pp_proof g ht es (entry :: c) t else find g ht t
106 and pp_letin g ht es c name v t =
107 let entry = Some (name, C.Def (v, None)) in
109 if DTI.does_not_occur 1 t then g (S.lift (-1) t) true decurry else
110 let g v proof d = match v with
111 | C.LetIn (mame, w, u) when proof ->
112 let x = C.LetIn (mame, w, C.LetIn (name, u, S.lift_from 2 1 t)) in
113 pp_proof g ht false c x
115 let v = eta_fix v proof d in
116 g (C.LetIn (name, v, t)) true decurry
118 if es then pp_term g ht es c v else find g ht v
120 if es then pp_proof g ht es (entry :: c) t else find g ht t
122 and pp_appl_one g ht es c t v =
126 | t, C.LetIn (mame, w, u) when proof ->
127 let x = C.LetIn (mame, w, C.Appl [S.lift 1 t; u]) in
128 pp_proof g ht false c x
129 | C.LetIn (mame, w, u), v ->
130 let x = C.LetIn (mame, w, C.Appl [u; S.lift 1 v]) in
131 pp_proof g ht false c x
132 | C.Appl ts, v when decurry > 0 ->
133 let v = eta_fix v proof d in
134 g (C.Appl (List.append ts [v])) true (pred decurry)
135 | t, v when is_not_atomic t ->
136 let mame = C.Name defined_premise in
137 let x = C.LetIn (mame, t, C.Appl [C.Rel 1; S.lift 1 v]) in
138 pp_proof g ht false c x
140 let _, premsno = split c (get_type c t) in
141 let v = eta_fix v proof d in
142 g (C.Appl [t; v]) true (pred premsno)
144 if es then pp_term g ht es c v else find g ht v
146 if es then pp_proof g ht es c t else find g ht t
148 and pp_appl g ht es c t = function
149 | [] -> pp_proof g ht es c t
150 | [v] -> pp_appl_one g ht es c t v
152 let x = C.Appl (C.Appl [t; v1] :: v2 :: vs) in
155 and pp_proof g ht es c t =
156 let g t proof decurry = add g ht t proof decurry in
158 | C.Cast (t, v) -> pp_cast g ht es c t v
159 | C.Lambda (name, v, t) -> pp_lambda g ht es c name v t
160 | C.LetIn (name, v, t) -> pp_letin g ht es c name v t
161 | C.Appl (t :: vs) -> pp_appl g ht es c t vs
164 and pp_term g ht es c t =
165 if is_proof c t then pp_proof g ht es c t else g t false 0
167 (* object preprocessing *****************************************************)
169 let pp_obj = function
170 | C.Constant (name, Some bo, ty, pars, attrs) ->
171 let g bo proof decurry =
172 let bo = eta_fix bo proof decurry in
173 C.Constant (name, Some bo, ty, pars, attrs)
175 let ht = C.CicHash.create 1 in
176 pp_term g ht true [] bo