aboutsummaryrefslogtreecommitdiffhomepage
path: root/parsing/esyntax.ml
blob: 2c0541f4ce8e3cef80b80f2abdb1953c471901ac (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
(***********************************************************************)
(*  v      *   The Coq Proof Assistant  /  The Coq Development Team    *)
(* <O___,, *        INRIA-Rocquencourt  &  LRI-CNRS-Orsay              *)
(*   \VV/  *************************************************************)
(*    //   *      This file is distributed under the terms of the      *)
(*         *       GNU Lesser General Public License Version 2.1       *)
(***********************************************************************)

(* $Id$ *)

open Pp
open Util
open Names
open Libnames
open Coqast
open Ast
open Extend
open Ppextend
open Vernacexpr
open Names
open Nametab
open Topconstr
open Symbols
 
(*** Syntax keys ***)

(* We define keys for ast and astpats. This is a kind of hash
 * function.  An ast may have several keys, but astpat only one. The
 * idea is that if an ast A matches a pattern P, then the key of P
 * is in the set of keys of A. Thus, we can split the syntax entries
 * according to the key of the pattern. *)

type key =
  | Cst of Names.constant (* keys for global constants rules *)
  | SecVar of Names.variable
  | Ind of Names.inductive
  | Cstr of Names.constructor
  | Nod of string      (* keys for other constructed asts rules *)
  | Oth                (* key for other syntax rules *)
  | All     (* key for catch-all rules (i.e. with a pattern such as $x .. *)

let warning_verbose = ref true

let ast_keys = function
  | Node(_,"APPLIST", Node(_,"CONST", [Path (_,sl)]) ::_) ->
      [Cst sl; Nod "APPLIST"; All]
  | Node(_,"APPLIST", Node(_,"SECVAR", [Nvar (_,s)]) ::_) ->
      [SecVar s; Nod "APPLIST"; All]
  | Node(_,"APPLIST", Node(_,"MUTIND", [Path (_,sl); Num (_,tyi)]) ::_) ->
      [Ind (sl,tyi); Nod "APPLIST"; All]
  | Node(_,"APPLIST", Node(_,"MUTCONSTRUCT",
			   [Path (_,sl); Num (_,tyi); Num (_,i)]) ::_) ->
      [Cstr ((sl,tyi),i); Nod "APPLIST"; All]
  | Node(_,s,_) -> [Nod s; All]
  | _ -> [Oth; All]

let spat_key astp =
  match astp with
    | Pnode("APPLIST",
            Pcons(Pnode("CONST",
                        Pcons(Pquote(Path (_,sl)),_)), _))
      -> Cst sl
    | Pnode("APPLIST",
            Pcons(Pnode("SECVAR",
                        Pcons(Pquote(Nvar (_,s)),_)), _))
      -> SecVar s
    | Pnode("APPLIST",
            Pcons(Pnode("MUTIND",
                        Pcons(Pquote(Path (_,sl)),
			      Pcons(Pquote(Num (_,tyi)),_))), _))
      -> Ind (sl,tyi)
    | Pnode("APPLIST",
            Pcons(Pnode("MUTCONSTRUCT",
                        Pcons(Pquote(Path (_,sl)),
			      Pcons(Pquote(Num (_,tyi)),
				    Pcons(Pquote(Num (_,i)),_)))), _))
      -> Cstr ((sl,tyi),i)
    | Pnode(na,_) -> Nod na
    | Pquote ast -> List.hd (ast_keys ast)
    | Pmeta _ -> All
    | _ -> Oth

let se_key se = spat_key se.syn_astpat

(** Syntax entry tables (state of the pretty_printer) **)
let from_name_table = ref Gmap.empty
let from_key_table = ref Gmapl.empty

(* Summary operations *)
type frozen_t = (string * string, astpat syntax_entry) Gmap.t * 
                (string * key, astpat syntax_entry) Gmapl.t

let freeze () =
  (!from_name_table, !from_key_table)

let unfreeze (fnm,fkm) =
  from_name_table := fnm;
  from_key_table := fkm

let init () =
  from_name_table := Gmap.empty;
  from_key_table := Gmapl.empty

let find_syntax_entry whatfor gt =
  let gt_keys = ast_keys gt in
  let entries =
    List.flatten
      (List.map (fun k -> Gmapl.find (whatfor,k) !from_key_table) gt_keys)
  in 
  find_all_matches (fun se -> se.syn_astpat) [] gt entries

let remove_with_warning name =
  if Gmap.mem name !from_name_table then begin
    let se = Gmap.find name !from_name_table in
    let key = (fst name, se_key se) in
    if !warning_verbose then
      (Options.if_verbose
    	warning ("overriding syntax rule "^(fst name)^":"^(snd name)^"."));
    from_name_table := Gmap.remove name !from_name_table;
    from_key_table := Gmapl.remove key se !from_key_table
  end

let add_rule whatfor se =
  let name = (whatfor,se.syn_id) in
  let key = (whatfor, se_key se) in
  remove_with_warning name;
  from_name_table := Gmap.add name se !from_name_table;
  from_key_table := Gmapl.add key se !from_key_table

let add_ppobject {sc_univ=wf;sc_entries=sel} = List.iter (add_rule wf) sel


(* Pretty-printing machinery *)

type std_printer = Coqast.t -> std_ppcmds
type unparsing_subfunction = string -> tolerability option -> std_printer
type primitive_printer = Coqast.t -> std_ppcmds option

(* Module of primitive printers *)
module Ppprim =
  struct
    type t = std_printer -> std_printer
    let tab = ref ([] : (string * t) list)
    let map a = List.assoc a !tab
    let add (a,ppr) = tab := (a,ppr)::!tab
  end

(**********************************************************************)
(* Primitive printers (e.g. for numerals)                             *)

(* This is the map associating to a printer the scope it belongs to   *)
(* and its ML code                                                    *)

let primitive_printer_tab = 
  ref (Stringmap.empty : (scope_name * primitive_printer) Stringmap.t)
let declare_primitive_printer s sc pp =
  primitive_printer_tab := Stringmap.add s (sc,pp) !primitive_printer_tab
let lookup_primitive_printer s =
  Stringmap.find s !primitive_printer_tab

(* Register the primitive printer for "token". It is not used in syntax/PP*.v,
 * but any ast matching no PP rule is printed with it. *)
(*
let _ = declare_primitive_printer "token" token_printer
*)

(* A printer for the tokens. *)
let token_printer stdpr = function
  | (Id _ | Num _ | Str _ | Path _ as ast) -> print_ast ast
  | a -> stdpr a

(* A primitive printer to do "print as" (to specify a length for a string) *)
let print_as_printer = function
  | Node (_, "AS", [Num(_,n); Str(_,s)]) -> Some (stras (n,s))
  | ast                                  -> None

let _ = declare_primitive_printer "print_as" default_scope print_as_printer

(* Handle infix symbols *)

let pr_parenthesis inherited se strm =
  if tolerable_prec inherited se.syn_prec then
    strm
  else 
    (str"(" ++ strm ++ str")")
    
let print_delimiters inh se strm = function
  | None -> pr_parenthesis inh se strm
  | Some key ->
      let left = "'"^key^":" and right = "'" in
      let lspace =
	if is_letter (left.[String.length left -1]) then str " " else mt () in
      let rspace =
        let c = right.[0] in
	if is_ident_tail c then str " " else mt () in
      hov 0 (str left ++ lspace ++ strm ++ rspace ++ str right)

(* Print the syntax entry. In the unparsing hunks, the tokens are
 * printed using the token_printer, unless another primitive printer
 * is specified. *)

let print_syntax_entry sub_pr scopes env se = 
  let rec print_hunk rule_prec scopes = function
    | PH(e,externpr,reln) ->
	let node = Ast.pat_sub dummy_loc env e in
	let printer =
	  match externpr with (* May branch to an other printer *)
	    | Some c ->
                (try (* Test for a primitive printer *) Ppprim.map c
                with Not_found -> token_printer)
	    | _ -> token_printer in
	printer (sub_pr scopes (Some(rule_prec,reln))) node
    | RO s -> str s
    | UNP_TAB -> tab ()
    | UNP_FNL -> fnl ()
    | UNP_BRK(n1,n2) -> brk(n1,n2)
    | UNP_TBRK(n1,n2) -> tbrk(n1,n2)
    | UNP_BOX (b,sub) -> ppcmd_of_box b (prlist (print_hunk rule_prec scopes) sub)
    | UNP_SYMBOLIC _ -> anomaly "handled by call_primitive_parser"
  in 
  prlist (print_hunk se.syn_prec scopes) se.syn_hunks

let call_primitive_parser rec_pr otherwise inherited scopes (se,env) =
  try (
  match se.syn_hunks with
    | [PH(e,Some c,reln)] ->
	  (* Test for a primitive printer; may raise Not_found *)
	  let sc,pr = lookup_primitive_printer c in
	  (* Look if scope [sc] associated to this printer is OK *)
	  (match Symbols.availability_of_numeral sc scopes with
	    | None -> otherwise ()
	    | Some key ->
	        (* We can use this printer *)
	        let node = Ast.pat_sub dummy_loc env e in
	        match pr node with
		  | Some strm -> print_delimiters inherited se strm key
		  | None -> otherwise ())
    | [UNP_SYMBOLIC (sc,pat,sub)] ->
	(match Symbols.availability_of_notation (sc,pat) scopes with
	  | None -> otherwise ()
	  | Some (scopt,key) ->
	      print_delimiters inherited se
		(print_syntax_entry rec_pr (option_cons scopt scopes) env 
		  {se with syn_hunks = [sub]}) key)
    | _ ->
	pr_parenthesis inherited se (print_syntax_entry rec_pr scopes env se)
  )
  with Not_found -> (* To handle old style printer *)
	pr_parenthesis inherited se (print_syntax_entry rec_pr scopes env se)

(* [genprint whatfor dflt inhprec ast] prints out the ast of
 * 'universe' whatfor. If the term is not matched by any
 * pretty-printing rule, then it will call dflt on it, which is
 * responsible for printing out the term (usually #GENTERM...).
 * In the case of tactics and commands, dflt also prints 
 * global constants basenames. *)

let genprint dflt whatfor inhprec ast =
  let rec rec_pr scopes inherited gt =
    let entries = find_syntax_entry whatfor gt in
    let rec test_rule = function
      | se_env::rules ->
	  call_primitive_parser
	    rec_pr 
	    (fun () -> test_rule rules) 
	    inherited scopes se_env
      | [] -> dflt gt (* No rule found *)
    in test_rule entries
  in
  try 
    rec_pr (Symbols.current_scopes ()) inhprec ast
  with
    | Failure _ -> (str"<PP failure: " ++ dflt ast ++ str">")
    | Not_found -> (str"<PP search failure: " ++ dflt ast ++ str">")