This file is indexed.

/usr/lib/ruby/vendor_ruby/treetop/compiler/metagrammar.treetop is in ruby-treetop 1.4.10-5.

This file is owned by root:root, with mode 0o644.

The actual contents of the file can be viewed below.

  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
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
module Treetop
  module Compiler
    grammar Metagrammar
      rule treetop_file
        requires:(space? require_statement)* prefix:space? module_or_grammar suffix:space? {
          def compile
            requires.text_value + prefix.text_value + module_or_grammar.compile + suffix.text_value
          end
        }
      end

      rule require_statement
        prefix:space? "require" [ \t]+ [^\n\r]+ [\n\r]
      end

      rule module_or_grammar
	module_declaration / grammar
      end

      rule module_declaration
        prefix:('module' space name:([A-Z] alphanumeric_char* ('::' [A-Z] alphanumeric_char*)*) space) module_contents:(module_declaration / grammar) suffix:(space 'end') {
          def compile
            prefix.text_value + module_contents.compile + suffix.text_value
          end

	  def parser_name
	    prefix.name.text_value+'::'+module_contents.parser_name
	  end
        }
      end

      rule grammar
        'grammar' space grammar_name space ('do' space)? declaration_sequence space? 'end' <Grammar>
      end

      rule grammar_name
        ([A-Z] alphanumeric_char*)
      end

      rule declaration_sequence
        head:declaration tail:(space declaration)* <DeclarationSequence> {
          def declarations
            [head] + tail
          end

          def tail
            super.elements.map { |elt| elt.declaration }
          end
        }
        /
        '' {
          def compile(builder)
          end
        }
      end

      rule declaration
        parsing_rule / include_declaration
      end

      rule include_declaration
        'include' space [A-Z] (alphanumeric_char / '::')* {
          def compile(builder)
            builder << text_value
          end
        }
      end

      rule parsing_rule
        'rule' space nonterminal space ('do' space)? parsing_expression space 'end' <ParsingRule>
      end

      rule parsing_expression
        choice / sequence / primary
      end

      rule choice
        head:alternative tail:(space? '/' space? alternative)+ <Choice> {
          def alternatives
            [head] + tail
          end

          def tail
            super.elements.map {|elt| elt.alternative}
          end

          def inline_modules
            (alternatives.map {|alt| alt.inline_modules }).flatten
          end
        }
      end

      rule sequence
        head:labeled_sequence_primary tail:(space labeled_sequence_primary)+ node_class_declarations <Sequence> {
          def sequence_elements
            [head] + tail
          end

          def tail
            super.elements.map {|elt| elt.labeled_sequence_primary }
          end

          def inline_modules
            (sequence_elements.map {|elt| elt.inline_modules}).flatten +
            [sequence_element_accessor_module] +
            node_class_declarations.inline_modules
          end

          def inline_module_name
            node_class_declarations.inline_module_name
          end
        }
      end

      rule alternative
        sequence / primary
      end

      rule primary
        prefix atomic {
          def compile(address, builder, parent_expression=nil)
            prefix.compile(address, builder, self)
          end

          def prefixed_expression
            atomic
          end

          def inline_modules
            atomic.inline_modules
          end

          def inline_module_name
            nil
          end
        }
        /
	prefix space? predicate_block {
          def compile(address, builder, parent_expression=nil)
            prefix.compile(address, builder, self)
          end
          def prefixed_expression
            predicate_block
          end
          def inline_modules
            []
          end
        }
        /
        atomic suffix node_class_declarations {
          def compile(address, builder, parent_expression=nil)
            suffix.compile(address, builder, self)
          end

          def optional_expression
            atomic
          end

          def node_class_name
            node_class_declarations.node_class_name
          end

          def inline_modules
            atomic.inline_modules + node_class_declarations.inline_modules
          end

          def inline_module_name
            node_class_declarations.inline_module_name
          end
        }
        /
        atomic node_class_declarations {
          def compile(address, builder, parent_expression=nil)
            atomic.compile(address, builder, self)
          end

          def node_class_name
            node_class_declarations.node_class_name
          end

          def inline_modules
            atomic.inline_modules + node_class_declarations.inline_modules
          end

          def inline_module_name
            node_class_declarations.inline_module_name
          end
        }
      end

      rule labeled_sequence_primary
        label sequence_primary {
          def compile(lexical_address, builder)
            sequence_primary.compile(lexical_address, builder)
          end

          def inline_modules
            sequence_primary.inline_modules
          end

          def label_name
            if label.name
              label.name
            elsif sequence_primary.instance_of?(Nonterminal)
              sequence_primary.text_value
            else
              nil
            end
          end
        }
      end

      rule label
        (alpha_char alphanumeric_char*) ':' {
          def name
            elements[0].text_value
          end
        }
        /
        '' {
          def name
            nil
          end
        }
      end

      rule sequence_primary
        prefix atomic {
          def compile(lexical_address, builder)
            prefix.compile(lexical_address, builder, self)
          end

          def prefixed_expression
            elements[1]
          end

          def inline_modules
            atomic.inline_modules
          end

          def inline_module_name
            nil
          end
        }
        /
        prefix space? predicate_block {
          def compile(address, builder, parent_expression=nil)
            prefix.compile(address, builder, self)
          end
          def prefixed_expression
            predicate_block
          end
          def inline_modules
            []
          end
        }
        /
        atomic suffix {
          def compile(lexical_address, builder)
            suffix.compile(lexical_address, builder, self)
          end

          def node_class_name
            nil
          end

          def inline_modules
            atomic.inline_modules
          end

          def inline_module_name
            nil
          end
        }
        /
        atomic
      end

      rule suffix
        repetition_suffix / optional_suffix
      end

      rule optional_suffix
        '?' <Optional>
      end

      rule node_class_declarations
        node_class_expression trailing_inline_module {
          def node_class_name
            node_class_expression.node_class_name
          end

          def inline_modules
            trailing_inline_module.inline_modules
          end

          def inline_module
            trailing_inline_module.inline_module
          end

          def inline_module_name
            inline_module.module_name if inline_module
          end
        }
      end

      rule repetition_suffix
        '+' <OneOrMore> / '*' <ZeroOrMore> / occurrence_range
      end

      rule occurrence_range
	space? min:([0-9])* '..' max:([0-9])* <OccurrenceRange>
      end

      rule prefix
        '&' <AndPredicate> / '!' <NotPredicate> / '~' <TransientPrefix>
      end

      rule atomic
        terminal
        /
        nonterminal
        /
        parenthesized_expression
      end

      rule parenthesized_expression
        '(' space? parsing_expression space? ')' <ParenthesizedExpression> {
          def inline_modules
            parsing_expression.inline_modules
          end
        }
      end

      rule nonterminal
        !keyword_inside_grammar (alpha_char alphanumeric_char*) <Nonterminal>
      end

      rule terminal
        quoted_string / character_class / anything_symbol
      end

      rule quoted_string
        (single_quoted_string / double_quoted_string) {
          def string
            super.text_value
          end
        }
      end

      rule double_quoted_string
        '"' string:(!'"' ("\\\\" / '\"' / .))* '"' <Terminal>
      end

      rule single_quoted_string
        "'" string:(!"'" ("\\\\" / "\\'" / .))* "'" <Terminal>
      end

      rule character_class
        '[' characters:(!']' ('\\' . /!'\\' .))+ ']' <CharacterClass> {
          def characters
            super.text_value
          end
        }
      end

      rule anything_symbol
        '.' <AnythingSymbol>
      end

      rule node_class_expression
        space '<' (!'>' .)+ '>' {
          def node_class_name
            elements[2].text_value
          end
        }
        /
        '' {
          def node_class_name
            nil
          end
        }
      end

      rule trailing_inline_module
        space inline_module {
          def inline_modules
            [inline_module]
          end

          def inline_module_name
            inline_module.module_name
          end
        }
        /
        '' {
          def inline_modules
            []
          end

          def inline_module
            nil
          end

          def inline_module_name
            nil
          end
        }
      end

      rule predicate_block
        '' inline_module <PredicateBlock>
      end

      rule inline_module
        '{' (inline_module / ![{}] .)* '}' <InlineModule>
      end

      rule keyword_inside_grammar
        ('rule' / 'end') !non_space_char
      end

      rule non_space_char
        !space .
      end

      rule alpha_char
        [A-Za-z_]
      end

      rule alphanumeric_char
        alpha_char / [0-9]
      end

      rule space
        (white / comment_to_eol)+
      end

      rule comment_to_eol
        '#' (!"\n" .)*
      end

      rule white
        [ \t\n\r]
      end
    end
  end
end