1 //===-- lib/Parser/Fortran-parsers.cpp ------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8
9 // Top-level grammar specification for Fortran. These parsers drive
10 // the tokenization parsers in cooked-tokens.h to consume characters,
11 // recognize the productions of Fortran, and to construct a parse tree.
12 // See ParserCombinators.md for documentation on the parser combinator
13 // library used here to implement an LL recursive descent recognizer.
14
15 // The productions that follow are derived from the draft Fortran 2018
16 // standard, with some necessary modifications to remove left recursion
17 // and some generalization in order to defer cases where parses depend
18 // on the definitions of symbols. The "Rxxx" numbers that appear in
19 // comments refer to these numbered requirements in the Fortran standard.
20
21 // The whole Fortran grammar originally constituted one header file,
22 // but that turned out to require more memory to compile with current
23 // C++ compilers than some people were willing to accept, so now the
24 // various per-type parsers are partitioned into several C++ source
25 // files. This file contains parsers for constants, types, declarations,
26 // and misfits (mostly clauses 7, 8, & 9 of Fortran 2018). The others:
27 // executable-parsers.cpp Executable statements
28 // expr-parsers.cpp Expressions
29 // io-parsers.cpp I/O statements and FORMAT
30 // openmp-parsers.cpp OpenMP directives
31 // program-parsers.cpp Program units
32
33 #include "basic-parsers.h"
34 #include "expr-parsers.h"
35 #include "misc-parsers.h"
36 #include "stmt-parser.h"
37 #include "token-parsers.h"
38 #include "type-parser-implementation.h"
39 #include "flang/Parser/parse-tree.h"
40 #include "flang/Parser/user-state.h"
41
42 namespace Fortran::parser {
43
44 // R601 alphanumeric-character -> letter | digit | underscore
45 // R603 name -> letter [alphanumeric-character]...
46 constexpr auto nonDigitIdChar{letter || otherIdChar};
47 constexpr auto rawName{nonDigitIdChar >> many(nonDigitIdChar || digit)};
48 TYPE_PARSER(space >> sourced(rawName >> construct<Name>()))
49
50 // R604 constant -> literal-constant | named-constant
51 // Used only via R607 int-constant and R845 data-stmt-constant.
52 // The look-ahead check prevents occlusion of constant-subobject in
53 // data-stmt-constant.
54 TYPE_PARSER(construct<ConstantValue>(literalConstant) ||
55 construct<ConstantValue>(namedConstant / !"%"_tok / !"("_tok))
56
57 // R608 intrinsic-operator ->
58 // power-op | mult-op | add-op | concat-op | rel-op |
59 // not-op | and-op | or-op | equiv-op
60 // R610 extended-intrinsic-op -> intrinsic-operator
61 // These parsers must be ordered carefully to avoid misrecognition.
62 constexpr auto namedIntrinsicOperator{
63 ".LT." >> pure(DefinedOperator::IntrinsicOperator::LT) ||
64 ".LE." >> pure(DefinedOperator::IntrinsicOperator::LE) ||
65 ".EQ." >> pure(DefinedOperator::IntrinsicOperator::EQ) ||
66 ".NE." >> pure(DefinedOperator::IntrinsicOperator::NE) ||
67 ".GE." >> pure(DefinedOperator::IntrinsicOperator::GE) ||
68 ".GT." >> pure(DefinedOperator::IntrinsicOperator::GT) ||
69 ".NOT." >> pure(DefinedOperator::IntrinsicOperator::NOT) ||
70 ".AND." >> pure(DefinedOperator::IntrinsicOperator::AND) ||
71 ".OR." >> pure(DefinedOperator::IntrinsicOperator::OR) ||
72 ".EQV." >> pure(DefinedOperator::IntrinsicOperator::EQV) ||
73 ".NEQV." >> pure(DefinedOperator::IntrinsicOperator::NEQV) ||
74 extension<LanguageFeature::XOROperator>(
75 ".XOR." >> pure(DefinedOperator::IntrinsicOperator::NEQV)) ||
76 extension<LanguageFeature::LogicalAbbreviations>(
77 ".N." >> pure(DefinedOperator::IntrinsicOperator::NOT) ||
78 ".A." >> pure(DefinedOperator::IntrinsicOperator::AND) ||
79 ".O." >> pure(DefinedOperator::IntrinsicOperator::OR) ||
80 extension<LanguageFeature::XOROperator>(
81 ".X." >> pure(DefinedOperator::IntrinsicOperator::NEQV)))};
82
83 constexpr auto intrinsicOperator{
84 "**" >> pure(DefinedOperator::IntrinsicOperator::Power) ||
85 "*" >> pure(DefinedOperator::IntrinsicOperator::Multiply) ||
86 "//" >> pure(DefinedOperator::IntrinsicOperator::Concat) ||
87 "/=" >> pure(DefinedOperator::IntrinsicOperator::NE) ||
88 "/" >> pure(DefinedOperator::IntrinsicOperator::Divide) ||
89 "+" >> pure(DefinedOperator::IntrinsicOperator::Add) ||
90 "-" >> pure(DefinedOperator::IntrinsicOperator::Subtract) ||
91 "<=" >> pure(DefinedOperator::IntrinsicOperator::LE) ||
92 extension<LanguageFeature::AlternativeNE>(
93 "<>" >> pure(DefinedOperator::IntrinsicOperator::NE)) ||
94 "<" >> pure(DefinedOperator::IntrinsicOperator::LT) ||
95 "==" >> pure(DefinedOperator::IntrinsicOperator::EQ) ||
96 ">=" >> pure(DefinedOperator::IntrinsicOperator::GE) ||
97 ">" >> pure(DefinedOperator::IntrinsicOperator::GT) ||
98 namedIntrinsicOperator};
99
100 // R609 defined-operator ->
101 // defined-unary-op | defined-binary-op | extended-intrinsic-op
102 TYPE_PARSER(construct<DefinedOperator>(intrinsicOperator) ||
103 construct<DefinedOperator>(definedOpName))
104
105 // R505 implicit-part -> [implicit-part-stmt]... implicit-stmt
106 // TODO: Can overshoot; any trailing PARAMETER, FORMAT, & ENTRY
107 // statements after the last IMPLICIT should be transferred to the
108 // list of declaration-constructs.
109 TYPE_CONTEXT_PARSER("implicit part"_en_US,
110 construct<ImplicitPart>(many(Parser<ImplicitPartStmt>{})))
111
112 // R506 implicit-part-stmt ->
113 // implicit-stmt | parameter-stmt | format-stmt | entry-stmt
TYPE_PARSER(first (construct<ImplicitPartStmt> (statement (indirect (Parser<ImplicitStmt>{}))),construct<ImplicitPartStmt> (statement (indirect (parameterStmt))),construct<ImplicitPartStmt> (statement (indirect (oldParameterStmt))),construct<ImplicitPartStmt> (statement (indirect (formatStmt))),construct<ImplicitPartStmt> (statement (indirect (entryStmt))),construct<ImplicitPartStmt> (indirect (compilerDirective))))114 TYPE_PARSER(first(
115 construct<ImplicitPartStmt>(statement(indirect(Parser<ImplicitStmt>{}))),
116 construct<ImplicitPartStmt>(statement(indirect(parameterStmt))),
117 construct<ImplicitPartStmt>(statement(indirect(oldParameterStmt))),
118 construct<ImplicitPartStmt>(statement(indirect(formatStmt))),
119 construct<ImplicitPartStmt>(statement(indirect(entryStmt))),
120 construct<ImplicitPartStmt>(indirect(compilerDirective))))
121
122 // R512 internal-subprogram -> function-subprogram | subroutine-subprogram
123 // Internal subprograms are not program units, so their END statements
124 // can be followed by ';' and another statement on the same line.
125 TYPE_CONTEXT_PARSER("internal subprogram"_en_US,
126 (construct<InternalSubprogram>(indirect(functionSubprogram)) ||
127 construct<InternalSubprogram>(indirect(subroutineSubprogram))) /
128 forceEndOfStmt)
129
130 // R511 internal-subprogram-part -> contains-stmt [internal-subprogram]...
131 TYPE_CONTEXT_PARSER("internal subprogram part"_en_US,
132 construct<InternalSubprogramPart>(statement(containsStmt),
133 many(StartNewSubprogram{} >> Parser<InternalSubprogram>{})))
134
135 // R605 literal-constant ->
136 // int-literal-constant | real-literal-constant |
137 // complex-literal-constant | logical-literal-constant |
138 // char-literal-constant | boz-literal-constant
139 TYPE_PARSER(
140 first(construct<LiteralConstant>(Parser<HollerithLiteralConstant>{}),
141 construct<LiteralConstant>(realLiteralConstant),
142 construct<LiteralConstant>(intLiteralConstant),
143 construct<LiteralConstant>(Parser<ComplexLiteralConstant>{}),
144 construct<LiteralConstant>(Parser<BOZLiteralConstant>{}),
145 construct<LiteralConstant>(charLiteralConstant),
146 construct<LiteralConstant>(Parser<LogicalLiteralConstant>{})))
147
148 // R606 named-constant -> name
149 TYPE_PARSER(construct<NamedConstant>(name))
150
151 // R701 type-param-value -> scalar-int-expr | * | :
152 TYPE_PARSER(construct<TypeParamValue>(scalarIntExpr) ||
153 construct<TypeParamValue>(star) ||
154 construct<TypeParamValue>(construct<TypeParamValue::Deferred>(":"_tok)))
155
156 // R702 type-spec -> intrinsic-type-spec | derived-type-spec
157 // N.B. This type-spec production is one of two instances in the Fortran
158 // grammar where intrinsic types and bare derived type names can clash;
159 // the other is below in R703 declaration-type-spec. Look-ahead is required
160 // to disambiguate the cases where a derived type name begins with the name
161 // of an intrinsic type, e.g., REALITY.
162 TYPE_CONTEXT_PARSER("type spec"_en_US,
163 construct<TypeSpec>(intrinsicTypeSpec / lookAhead("::"_tok || ")"_tok)) ||
164 construct<TypeSpec>(derivedTypeSpec))
165
166 // R703 declaration-type-spec ->
167 // intrinsic-type-spec | TYPE ( intrinsic-type-spec ) |
168 // TYPE ( derived-type-spec ) | CLASS ( derived-type-spec ) |
169 // CLASS ( * ) | TYPE ( * )
170 // N.B. It is critical to distribute "parenthesized()" over the alternatives
171 // for TYPE (...), rather than putting the alternatives within it, which
172 // would fail on "TYPE(real_derived)" with a misrecognition of "real" as an
173 // intrinsic-type-spec.
174 TYPE_CONTEXT_PARSER("declaration type spec"_en_US,
175 construct<DeclarationTypeSpec>(intrinsicTypeSpec) ||
176 "TYPE" >>
177 (parenthesized(construct<DeclarationTypeSpec>(intrinsicTypeSpec)) ||
178 parenthesized(construct<DeclarationTypeSpec>(
179 construct<DeclarationTypeSpec::Type>(derivedTypeSpec))) ||
180 construct<DeclarationTypeSpec>(
181 "( * )" >> construct<DeclarationTypeSpec::TypeStar>())) ||
182 "CLASS" >> parenthesized(construct<DeclarationTypeSpec>(
183 construct<DeclarationTypeSpec::Class>(
184 derivedTypeSpec)) ||
185 construct<DeclarationTypeSpec>("*" >>
186 construct<DeclarationTypeSpec::ClassStar>())) ||
187 extension<LanguageFeature::DECStructures>(
188 construct<DeclarationTypeSpec>(
189 construct<DeclarationTypeSpec::Record>(
190 "RECORD /" >> name / "/"))))
191
192 // R704 intrinsic-type-spec ->
193 // integer-type-spec | REAL [kind-selector] | DOUBLE PRECISION |
194 // COMPLEX [kind-selector] | CHARACTER [char-selector] |
195 // LOGICAL [kind-selector]
196 // Extensions: DOUBLE COMPLEX, BYTE
197 TYPE_CONTEXT_PARSER("intrinsic type spec"_en_US,
198 first(construct<IntrinsicTypeSpec>(integerTypeSpec),
199 construct<IntrinsicTypeSpec>(
200 construct<IntrinsicTypeSpec::Real>("REAL" >> maybe(kindSelector))),
201 construct<IntrinsicTypeSpec>("DOUBLE PRECISION" >>
202 construct<IntrinsicTypeSpec::DoublePrecision>()),
203 construct<IntrinsicTypeSpec>(construct<IntrinsicTypeSpec::Complex>(
204 "COMPLEX" >> maybe(kindSelector))),
205 construct<IntrinsicTypeSpec>(construct<IntrinsicTypeSpec::Character>(
206 "CHARACTER" >> maybe(Parser<CharSelector>{}))),
207 construct<IntrinsicTypeSpec>(construct<IntrinsicTypeSpec::Logical>(
208 "LOGICAL" >> maybe(kindSelector))),
209 construct<IntrinsicTypeSpec>("DOUBLE COMPLEX" >>
210 extension<LanguageFeature::DoubleComplex>(
211 construct<IntrinsicTypeSpec::DoubleComplex>())),
212 extension<LanguageFeature::Byte>(
213 construct<IntrinsicTypeSpec>(construct<IntegerTypeSpec>(
214 "BYTE" >> construct<std::optional<KindSelector>>(pure(1)))))))
215
216 // R705 integer-type-spec -> INTEGER [kind-selector]
217 TYPE_PARSER(construct<IntegerTypeSpec>("INTEGER" >> maybe(kindSelector)))
218
219 // R706 kind-selector -> ( [KIND =] scalar-int-constant-expr )
220 // Legacy extension: kind-selector -> * digit-string
221 TYPE_PARSER(construct<KindSelector>(
222 parenthesized(maybe("KIND ="_tok) >> scalarIntConstantExpr)) ||
223 extension<LanguageFeature::StarKind>(construct<KindSelector>(
224 construct<KindSelector::StarSize>("*" >> digitString64 / spaceCheck))))
225
226 // R707 signed-int-literal-constant -> [sign] int-literal-constant
227 TYPE_PARSER(sourced(construct<SignedIntLiteralConstant>(
228 SignedIntLiteralConstantWithoutKind{}, maybe(underscore >> kindParam))))
229
230 // R708 int-literal-constant -> digit-string [_ kind-param]
231 // The negated look-ahead for a trailing underscore prevents misrecognition
232 // when the digit string is a numeric kind parameter of a character literal.
233 TYPE_PARSER(construct<IntLiteralConstant>(
234 space >> digitString, maybe(underscore >> kindParam) / !underscore))
235
236 // R709 kind-param -> digit-string | scalar-int-constant-name
237 TYPE_PARSER(construct<KindParam>(digitString64) ||
238 construct<KindParam>(scalar(integer(constant(name)))))
239
240 // R712 sign -> + | -
241 // N.B. A sign constitutes a whole token, so a space is allowed in free form
242 // after the sign and before a real-literal-constant or
243 // complex-literal-constant. A sign is not a unary operator in these contexts.
244 constexpr auto sign{
245 "+"_tok >> pure(Sign::Positive) || "-"_tok >> pure(Sign::Negative)};
246
247 // R713 signed-real-literal-constant -> [sign] real-literal-constant
248 constexpr auto signedRealLiteralConstant{
249 construct<SignedRealLiteralConstant>(maybe(sign), realLiteralConstant)};
250
251 // R714 real-literal-constant ->
252 // significand [exponent-letter exponent] [_ kind-param] |
253 // digit-string exponent-letter exponent [_ kind-param]
254 // R715 significand -> digit-string . [digit-string] | . digit-string
255 // R716 exponent-letter -> E | D
256 // Extension: Q
257 // R717 exponent -> signed-digit-string
258 constexpr auto exponentPart{
259 ("ed"_ch || extension<LanguageFeature::QuadPrecision>("q"_ch)) >>
260 SignedDigitString{}};
261
262 TYPE_CONTEXT_PARSER("REAL literal constant"_en_US,
263 space >>
264 construct<RealLiteralConstant>(
265 sourced((digitString >> "."_ch >>
266 !(some(letter) >>
267 "."_ch /* don't misinterpret 1.AND. */) >>
268 maybe(digitString) >> maybe(exponentPart) >> ok ||
269 "."_ch >> digitString >> maybe(exponentPart) >> ok ||
270 digitString >> exponentPart >> ok) >>
271 construct<RealLiteralConstant::Real>()),
272 maybe(underscore >> kindParam)))
273
274 // R718 complex-literal-constant -> ( real-part , imag-part )
275 TYPE_CONTEXT_PARSER("COMPLEX literal constant"_en_US,
276 parenthesized(construct<ComplexLiteralConstant>(
277 Parser<ComplexPart>{} / ",", Parser<ComplexPart>{})))
278
279 // PGI/Intel extension: signed complex literal constant
TYPE_PARSER(construct<SignedComplexLiteralConstant> (sign,Parser<ComplexLiteralConstant>{}))280 TYPE_PARSER(construct<SignedComplexLiteralConstant>(
281 sign, Parser<ComplexLiteralConstant>{}))
282
283 // R719 real-part ->
284 // signed-int-literal-constant | signed-real-literal-constant |
285 // named-constant
286 // R720 imag-part ->
287 // signed-int-literal-constant | signed-real-literal-constant |
288 // named-constant
289 TYPE_PARSER(construct<ComplexPart>(signedRealLiteralConstant) ||
290 construct<ComplexPart>(signedIntLiteralConstant) ||
291 construct<ComplexPart>(namedConstant))
292
293 // R721 char-selector ->
294 // length-selector |
295 // ( LEN = type-param-value , KIND = scalar-int-constant-expr ) |
296 // ( type-param-value , [KIND =] scalar-int-constant-expr ) |
297 // ( KIND = scalar-int-constant-expr [, LEN = type-param-value] )
298 TYPE_PARSER(construct<CharSelector>(Parser<LengthSelector>{}) ||
299 parenthesized(construct<CharSelector>(
300 "LEN =" >> typeParamValue, ", KIND =" >> scalarIntConstantExpr)) ||
301 parenthesized(construct<CharSelector>(
302 typeParamValue / ",", maybe("KIND ="_tok) >> scalarIntConstantExpr)) ||
303 parenthesized(construct<CharSelector>(
304 "KIND =" >> scalarIntConstantExpr, maybe(", LEN =" >> typeParamValue))))
305
306 // R722 length-selector -> ( [LEN =] type-param-value ) | * char-length [,]
307 // N.B. The trailing [,] in the production is permitted by the Standard
308 // only in the context of a type-declaration-stmt, but even with that
309 // limitation, it would seem to be unnecessary and buggy to consume the comma
310 // here.
311 TYPE_PARSER(construct<LengthSelector>(
312 parenthesized(maybe("LEN ="_tok) >> typeParamValue)) ||
313 construct<LengthSelector>("*" >> charLength /* / maybe(","_tok) */))
314
315 // R723 char-length -> ( type-param-value ) | digit-string
316 TYPE_PARSER(construct<CharLength>(parenthesized(typeParamValue)) ||
317 construct<CharLength>(space >> digitString64 / spaceCheck))
318
319 // R724 char-literal-constant ->
320 // [kind-param _] ' [rep-char]... ' |
321 // [kind-param _] " [rep-char]... "
322 // "rep-char" is any non-control character. Doubled interior quotes are
323 // combined. Backslash escapes can be enabled.
324 // N.B. the parsing of "kind-param" takes care to not consume the '_'.
325 TYPE_CONTEXT_PARSER("CHARACTER literal constant"_en_US,
326 construct<CharLiteralConstant>(
327 kindParam / underscore, charLiteralConstantWithoutKind) ||
328 construct<CharLiteralConstant>(construct<std::optional<KindParam>>(),
329 space >> charLiteralConstantWithoutKind))
330
331 TYPE_CONTEXT_PARSER(
332 "Hollerith"_en_US, construct<HollerithLiteralConstant>(rawHollerithLiteral))
333
334 // R725 logical-literal-constant ->
335 // .TRUE. [_ kind-param] | .FALSE. [_ kind-param]
336 // Also accept .T. and .F. as extensions.
337 TYPE_PARSER(construct<LogicalLiteralConstant>(
338 logicalTRUE, maybe(underscore >> kindParam)) ||
339 construct<LogicalLiteralConstant>(
340 logicalFALSE, maybe(underscore >> kindParam)))
341
342 // R726 derived-type-def ->
343 // derived-type-stmt [type-param-def-stmt]...
344 // [private-or-sequence]... [component-part]
345 // [type-bound-procedure-part] end-type-stmt
346 // R735 component-part -> [component-def-stmt]...
347 TYPE_CONTEXT_PARSER("derived type definition"_en_US,
348 construct<DerivedTypeDef>(statement(Parser<DerivedTypeStmt>{}),
349 many(unambiguousStatement(Parser<TypeParamDefStmt>{})),
350 many(statement(Parser<PrivateOrSequence>{})),
351 many(inContext("component"_en_US,
352 unambiguousStatement(Parser<ComponentDefStmt>{}))),
353 maybe(Parser<TypeBoundProcedurePart>{}),
354 statement(Parser<EndTypeStmt>{})))
355
356 // R727 derived-type-stmt ->
357 // TYPE [[, type-attr-spec-list] ::] type-name [(
358 // type-param-name-list )]
359 TYPE_CONTEXT_PARSER("TYPE statement"_en_US,
360 construct<DerivedTypeStmt>(
361 "TYPE" >> optionalListBeforeColons(Parser<TypeAttrSpec>{}), name,
362 defaulted(parenthesized(nonemptyList(name)))))
363
364 // R728 type-attr-spec ->
365 // ABSTRACT | access-spec | BIND(C) | EXTENDS ( parent-type-name )
366 TYPE_PARSER(construct<TypeAttrSpec>(construct<Abstract>("ABSTRACT"_tok)) ||
367 construct<TypeAttrSpec>(construct<TypeAttrSpec::BindC>("BIND ( C )"_tok)) ||
368 construct<TypeAttrSpec>(
369 construct<TypeAttrSpec::Extends>("EXTENDS" >> parenthesized(name))) ||
370 construct<TypeAttrSpec>(accessSpec))
371
372 // R729 private-or-sequence -> private-components-stmt | sequence-stmt
373 TYPE_PARSER(construct<PrivateOrSequence>(Parser<PrivateStmt>{}) ||
374 construct<PrivateOrSequence>(Parser<SequenceStmt>{}))
375
376 // R730 end-type-stmt -> END TYPE [type-name]
377 TYPE_PARSER(construct<EndTypeStmt>(
378 recovery("END TYPE" >> maybe(name), endStmtErrorRecovery)))
379
380 // R731 sequence-stmt -> SEQUENCE
381 TYPE_PARSER(construct<SequenceStmt>("SEQUENCE"_tok))
382
383 // R732 type-param-def-stmt ->
384 // integer-type-spec , type-param-attr-spec :: type-param-decl-list
385 // R734 type-param-attr-spec -> KIND | LEN
386 constexpr auto kindOrLen{"KIND" >> pure(common::TypeParamAttr::Kind) ||
387 "LEN" >> pure(common::TypeParamAttr::Len)};
388 TYPE_PARSER(construct<TypeParamDefStmt>(integerTypeSpec / ",", kindOrLen,
389 "::" >> nonemptyList("expected type parameter declarations"_err_en_US,
390 Parser<TypeParamDecl>{})))
391
392 // R733 type-param-decl -> type-param-name [= scalar-int-constant-expr]
393 TYPE_PARSER(construct<TypeParamDecl>(name, maybe("=" >> scalarIntConstantExpr)))
394
395 // R736 component-def-stmt -> data-component-def-stmt |
396 // proc-component-def-stmt
397 // Accidental extension not enabled here: PGI accepts type-param-def-stmt in
398 // component-part of derived-type-def.
399 TYPE_PARSER(recovery(
400 withMessage("expected component definition"_err_en_US,
401 first(construct<ComponentDefStmt>(Parser<DataComponentDefStmt>{}),
402 construct<ComponentDefStmt>(Parser<ProcComponentDefStmt>{}))),
403 construct<ComponentDefStmt>(inStmtErrorRecovery)))
404
405 // R737 data-component-def-stmt ->
406 // declaration-type-spec [[, component-attr-spec-list] ::]
407 // component-decl-list
408 // N.B. The standard requires double colons if there's an initializer.
409 TYPE_PARSER(construct<DataComponentDefStmt>(declarationTypeSpec,
410 optionalListBeforeColons(Parser<ComponentAttrSpec>{}),
411 nonemptyList(
412 "expected component declarations"_err_en_US, Parser<ComponentDecl>{})))
413
414 // R738 component-attr-spec ->
415 // access-spec | ALLOCATABLE |
416 // CODIMENSION lbracket coarray-spec rbracket |
417 // CONTIGUOUS | DIMENSION ( component-array-spec ) | POINTER
418 TYPE_PARSER(construct<ComponentAttrSpec>(accessSpec) ||
419 construct<ComponentAttrSpec>(allocatable) ||
420 construct<ComponentAttrSpec>("CODIMENSION" >> coarraySpec) ||
421 construct<ComponentAttrSpec>(contiguous) ||
422 construct<ComponentAttrSpec>("DIMENSION" >> Parser<ComponentArraySpec>{}) ||
423 construct<ComponentAttrSpec>(pointer) ||
424 construct<ComponentAttrSpec>(recovery(
425 fail<ErrorRecovery>(
426 "type parameter definitions must appear before component declarations"_err_en_US),
427 kindOrLen >> construct<ErrorRecovery>())))
428
429 // R739 component-decl ->
430 // component-name [( component-array-spec )]
431 // [lbracket coarray-spec rbracket] [* char-length]
432 // [component-initialization]
433 TYPE_CONTEXT_PARSER("component declaration"_en_US,
434 construct<ComponentDecl>(name, maybe(Parser<ComponentArraySpec>{}),
435 maybe(coarraySpec), maybe("*" >> charLength), maybe(initialization)))
436
437 // R740 component-array-spec ->
438 // explicit-shape-spec-list | deferred-shape-spec-list
439 // N.B. Parenthesized here rather than around references to this production.
440 TYPE_PARSER(construct<ComponentArraySpec>(parenthesized(
441 nonemptyList("expected explicit shape specifications"_err_en_US,
442 explicitShapeSpec))) ||
443 construct<ComponentArraySpec>(parenthesized(deferredShapeSpecList)))
444
445 // R741 proc-component-def-stmt ->
446 // PROCEDURE ( [proc-interface] ) , proc-component-attr-spec-list
447 // :: proc-decl-list
448 TYPE_CONTEXT_PARSER("PROCEDURE component definition statement"_en_US,
449 construct<ProcComponentDefStmt>(
450 "PROCEDURE" >> parenthesized(maybe(procInterface)),
451 localRecovery("expected PROCEDURE component attributes"_err_en_US,
452 "," >> nonemptyList(Parser<ProcComponentAttrSpec>{}), ok),
453 localRecovery("expected PROCEDURE declarations"_err_en_US,
454 "::" >> nonemptyList(procDecl), SkipTo<'\n'>{})))
455
456 // R742 proc-component-attr-spec ->
457 // access-spec | NOPASS | PASS [(arg-name)] | POINTER
458 constexpr auto noPass{construct<NoPass>("NOPASS"_tok)};
459 constexpr auto pass{construct<Pass>("PASS" >> maybe(parenthesized(name)))};
460 TYPE_PARSER(construct<ProcComponentAttrSpec>(accessSpec) ||
461 construct<ProcComponentAttrSpec>(noPass) ||
462 construct<ProcComponentAttrSpec>(pass) ||
463 construct<ProcComponentAttrSpec>(pointer))
464
465 // R744 initial-data-target -> designator
466 constexpr auto initialDataTarget{indirect(designator)};
467
468 // R743 component-initialization ->
469 // = constant-expr | => null-init | => initial-data-target
470 // R805 initialization ->
471 // = constant-expr | => null-init | => initial-data-target
472 // Universal extension: initialization -> / data-stmt-value-list /
473 TYPE_PARSER(construct<Initialization>("=>" >> nullInit) ||
474 construct<Initialization>("=>" >> initialDataTarget) ||
475 construct<Initialization>("=" >> constantExpr) ||
476 extension<LanguageFeature::SlashInitialization>(construct<Initialization>(
477 "/" >> nonemptyList("expected values"_err_en_US,
478 indirect(Parser<DataStmtValue>{})) /
479 "/")))
480
481 // R745 private-components-stmt -> PRIVATE
482 // R747 binding-private-stmt -> PRIVATE
483 TYPE_PARSER(construct<PrivateStmt>("PRIVATE"_tok))
484
485 // R746 type-bound-procedure-part ->
486 // contains-stmt [binding-private-stmt] [type-bound-proc-binding]...
487 TYPE_CONTEXT_PARSER("type bound procedure part"_en_US,
488 construct<TypeBoundProcedurePart>(statement(containsStmt),
489 maybe(statement(Parser<PrivateStmt>{})),
490 many(statement(Parser<TypeBoundProcBinding>{}))))
491
492 // R748 type-bound-proc-binding ->
493 // type-bound-procedure-stmt | type-bound-generic-stmt |
494 // final-procedure-stmt
495 TYPE_CONTEXT_PARSER("type bound procedure binding"_en_US,
496 recovery(
497 first(construct<TypeBoundProcBinding>(Parser<TypeBoundProcedureStmt>{}),
498 construct<TypeBoundProcBinding>(Parser<TypeBoundGenericStmt>{}),
499 construct<TypeBoundProcBinding>(Parser<FinalProcedureStmt>{})),
500 construct<TypeBoundProcBinding>(
501 !"END"_tok >> SkipTo<'\n'>{} >> construct<ErrorRecovery>())))
502
503 // R749 type-bound-procedure-stmt ->
504 // PROCEDURE [[, bind-attr-list] ::] type-bound-proc-decl-list |
505 // PROCEDURE ( interface-name ) , bind-attr-list :: binding-name-list
506 TYPE_CONTEXT_PARSER("type bound PROCEDURE statement"_en_US,
507 "PROCEDURE" >>
508 (construct<TypeBoundProcedureStmt>(
509 construct<TypeBoundProcedureStmt::WithInterface>(
510 parenthesized(name),
511 localRecovery("expected list of binding attributes"_err_en_US,
512 "," >> nonemptyList(Parser<BindAttr>{}), ok),
513 localRecovery("expected list of binding names"_err_en_US,
514 "::" >> listOfNames, SkipTo<'\n'>{}))) ||
515 construct<TypeBoundProcedureStmt>(
516 construct<TypeBoundProcedureStmt::WithoutInterface>(
517 optionalListBeforeColons(Parser<BindAttr>{}),
518 nonemptyList(
519 "expected type bound procedure declarations"_err_en_US,
520 Parser<TypeBoundProcDecl>{})))))
521
522 // R750 type-bound-proc-decl -> binding-name [=> procedure-name]
523 TYPE_PARSER(construct<TypeBoundProcDecl>(name, maybe("=>" >> name)))
524
525 // R751 type-bound-generic-stmt ->
526 // GENERIC [, access-spec] :: generic-spec => binding-name-list
527 TYPE_CONTEXT_PARSER("type bound GENERIC statement"_en_US,
528 construct<TypeBoundGenericStmt>("GENERIC" >> maybe("," >> accessSpec),
529 "::" >> indirect(genericSpec), "=>" >> listOfNames))
530
531 // R752 bind-attr ->
532 // access-spec | DEFERRED | NON_OVERRIDABLE | NOPASS | PASS [(arg-name)]
533 TYPE_PARSER(construct<BindAttr>(accessSpec) ||
534 construct<BindAttr>(construct<BindAttr::Deferred>("DEFERRED"_tok)) ||
535 construct<BindAttr>(
536 construct<BindAttr::Non_Overridable>("NON_OVERRIDABLE"_tok)) ||
537 construct<BindAttr>(noPass) || construct<BindAttr>(pass))
538
539 // R753 final-procedure-stmt -> FINAL [::] final-subroutine-name-list
540 TYPE_CONTEXT_PARSER("FINAL statement"_en_US,
541 construct<FinalProcedureStmt>("FINAL" >> maybe("::"_tok) >> listOfNames))
542
543 // R754 derived-type-spec -> type-name [(type-param-spec-list)]
544 TYPE_PARSER(construct<DerivedTypeSpec>(name,
545 defaulted(parenthesized(nonemptyList(
546 "expected type parameters"_err_en_US, Parser<TypeParamSpec>{})))))
547
548 // R755 type-param-spec -> [keyword =] type-param-value
549 TYPE_PARSER(construct<TypeParamSpec>(maybe(keyword / "="), typeParamValue))
550
551 // R756 structure-constructor -> derived-type-spec ( [component-spec-list] )
552 TYPE_PARSER((construct<StructureConstructor>(derivedTypeSpec,
553 parenthesized(optionalList(Parser<ComponentSpec>{}))) ||
554 // This alternative corrects misrecognition of the
555 // component-spec-list as the type-param-spec-list in
556 // derived-type-spec.
557 construct<StructureConstructor>(
558 construct<DerivedTypeSpec>(
559 name, construct<std::list<TypeParamSpec>>()),
560 parenthesized(optionalList(Parser<ComponentSpec>{})))) /
561 !"("_tok)
562
563 // R757 component-spec -> [keyword =] component-data-source
564 TYPE_PARSER(construct<ComponentSpec>(
565 maybe(keyword / "="), Parser<ComponentDataSource>{}))
566
567 // R758 component-data-source -> expr | data-target | proc-target
TYPE_PARSER(construct<ComponentDataSource> (indirect (expr)))568 TYPE_PARSER(construct<ComponentDataSource>(indirect(expr)))
569
570 // R759 enum-def ->
571 // enum-def-stmt enumerator-def-stmt [enumerator-def-stmt]...
572 // end-enum-stmt
573 TYPE_CONTEXT_PARSER("enum definition"_en_US,
574 construct<EnumDef>(statement(Parser<EnumDefStmt>{}),
575 some(unambiguousStatement(Parser<EnumeratorDefStmt>{})),
576 statement(Parser<EndEnumStmt>{})))
577
578 // R760 enum-def-stmt -> ENUM, BIND(C)
579 TYPE_PARSER(construct<EnumDefStmt>("ENUM , BIND ( C )"_tok))
580
581 // R761 enumerator-def-stmt -> ENUMERATOR [::] enumerator-list
582 TYPE_CONTEXT_PARSER("ENUMERATOR statement"_en_US,
583 construct<EnumeratorDefStmt>("ENUMERATOR" >> maybe("::"_tok) >>
584 nonemptyList("expected enumerators"_err_en_US, Parser<Enumerator>{})))
585
586 // R762 enumerator -> named-constant [= scalar-int-constant-expr]
587 TYPE_PARSER(
588 construct<Enumerator>(namedConstant, maybe("=" >> scalarIntConstantExpr)))
589
590 // R763 end-enum-stmt -> END ENUM
591 TYPE_PARSER(recovery("END ENUM"_tok, "END" >> SkipPast<'\n'>{}) >>
592 construct<EndEnumStmt>())
593
594 // R801 type-declaration-stmt ->
595 // declaration-type-spec [[, attr-spec]... ::] entity-decl-list
596 constexpr auto entityDeclWithoutEqInit{construct<EntityDecl>(name,
597 maybe(arraySpec), maybe(coarraySpec), maybe("*" >> charLength),
598 !"="_tok >> maybe(initialization))}; // old-style REAL A/0/ still works
599 TYPE_PARSER(
600 construct<TypeDeclarationStmt>(declarationTypeSpec,
601 defaulted("," >> nonemptyList(Parser<AttrSpec>{})) / "::",
602 nonemptyList("expected entity declarations"_err_en_US, entityDecl)) ||
603 // C806: no initializers allowed without colons ("REALA=1" is ambiguous)
604 construct<TypeDeclarationStmt>(declarationTypeSpec,
605 construct<std::list<AttrSpec>>(),
606 nonemptyList("expected entity declarations"_err_en_US,
607 entityDeclWithoutEqInit)) ||
608 // PGI-only extension: comma in place of doubled colons
609 extension<LanguageFeature::MissingColons>(construct<TypeDeclarationStmt>(
610 declarationTypeSpec, defaulted("," >> nonemptyList(Parser<AttrSpec>{})),
611 withMessage("expected entity declarations"_err_en_US,
612 "," >> nonemptyList(entityDecl)))))
613
614 // R802 attr-spec ->
615 // access-spec | ALLOCATABLE | ASYNCHRONOUS |
616 // CODIMENSION lbracket coarray-spec rbracket | CONTIGUOUS |
617 // DIMENSION ( array-spec ) | EXTERNAL | INTENT ( intent-spec ) |
618 // INTRINSIC | language-binding-spec | OPTIONAL | PARAMETER | POINTER |
619 // PROTECTED | SAVE | TARGET | VALUE | VOLATILE
620 TYPE_PARSER(construct<AttrSpec>(accessSpec) ||
621 construct<AttrSpec>(allocatable) ||
622 construct<AttrSpec>(construct<Asynchronous>("ASYNCHRONOUS"_tok)) ||
623 construct<AttrSpec>("CODIMENSION" >> coarraySpec) ||
624 construct<AttrSpec>(contiguous) ||
625 construct<AttrSpec>("DIMENSION" >> arraySpec) ||
626 construct<AttrSpec>(construct<External>("EXTERNAL"_tok)) ||
627 construct<AttrSpec>("INTENT" >> parenthesized(intentSpec)) ||
628 construct<AttrSpec>(construct<Intrinsic>("INTRINSIC"_tok)) ||
629 construct<AttrSpec>(languageBindingSpec) || construct<AttrSpec>(optional) ||
630 construct<AttrSpec>(construct<Parameter>("PARAMETER"_tok)) ||
631 construct<AttrSpec>(pointer) || construct<AttrSpec>(protectedAttr) ||
632 construct<AttrSpec>(save) ||
633 construct<AttrSpec>(construct<Target>("TARGET"_tok)) ||
634 construct<AttrSpec>(construct<Value>("VALUE"_tok)) ||
635 construct<AttrSpec>(construct<Volatile>("VOLATILE"_tok)))
636
637 // R804 object-name -> name
638 constexpr auto objectName{name};
639
640 // R803 entity-decl ->
641 // object-name [( array-spec )] [lbracket coarray-spec rbracket]
642 // [* char-length] [initialization] |
643 // function-name [* char-length]
644 TYPE_PARSER(construct<EntityDecl>(objectName, maybe(arraySpec),
645 maybe(coarraySpec), maybe("*" >> charLength), maybe(initialization)))
646
647 // R806 null-init -> function-reference ... which must resolve to NULL()
648 TYPE_PARSER(lookAhead(name / "( )") >> construct<NullInit>(expr))
649
650 // R807 access-spec -> PUBLIC | PRIVATE
651 TYPE_PARSER(construct<AccessSpec>("PUBLIC" >> pure(AccessSpec::Kind::Public)) ||
652 construct<AccessSpec>("PRIVATE" >> pure(AccessSpec::Kind::Private)))
653
654 // R808 language-binding-spec ->
655 // BIND ( C [, NAME = scalar-default-char-constant-expr] )
656 // R1528 proc-language-binding-spec -> language-binding-spec
657 TYPE_PARSER(construct<LanguageBindingSpec>(
658 "BIND ( C" >> maybe(", NAME =" >> scalarDefaultCharConstantExpr) / ")"))
659
660 // R809 coarray-spec -> deferred-coshape-spec-list | explicit-coshape-spec
661 // N.B. Bracketed here rather than around references, for consistency with
662 // array-spec.
663 TYPE_PARSER(
664 construct<CoarraySpec>(bracketed(Parser<DeferredCoshapeSpecList>{})) ||
665 construct<CoarraySpec>(bracketed(Parser<ExplicitCoshapeSpec>{})))
666
667 // R810 deferred-coshape-spec -> :
668 // deferred-coshape-spec-list - just a list of colons
listLength(std::list<Success> && xs)669 inline int listLength(std::list<Success> &&xs) { return xs.size(); }
670
671 TYPE_PARSER(construct<DeferredCoshapeSpecList>(
672 applyFunction(listLength, nonemptyList(":"_tok))))
673
674 // R811 explicit-coshape-spec ->
675 // [[lower-cobound :] upper-cobound ,]... [lower-cobound :] *
676 // R812 lower-cobound -> specification-expr
677 // R813 upper-cobound -> specification-expr
678 TYPE_PARSER(construct<ExplicitCoshapeSpec>(
679 many(explicitShapeSpec / ","), maybe(specificationExpr / ":") / "*"))
680
681 // R815 array-spec ->
682 // explicit-shape-spec-list | assumed-shape-spec-list |
683 // deferred-shape-spec-list | assumed-size-spec | implied-shape-spec |
684 // implied-shape-or-assumed-size-spec | assumed-rank-spec
685 // N.B. Parenthesized here rather than around references to avoid
686 // a need for forced look-ahead.
687 // Shape specs that could be deferred-shape-spec or assumed-shape-spec
688 // (e.g. '(:,:)') are parsed as the former.
689 TYPE_PARSER(
690 construct<ArraySpec>(parenthesized(nonemptyList(explicitShapeSpec))) ||
691 construct<ArraySpec>(parenthesized(deferredShapeSpecList)) ||
692 construct<ArraySpec>(
693 parenthesized(nonemptyList(Parser<AssumedShapeSpec>{}))) ||
694 construct<ArraySpec>(parenthesized(Parser<AssumedSizeSpec>{})) ||
695 construct<ArraySpec>(parenthesized(Parser<ImpliedShapeSpec>{})) ||
696 construct<ArraySpec>(parenthesized(Parser<AssumedRankSpec>{})))
697
698 // R816 explicit-shape-spec -> [lower-bound :] upper-bound
699 // R817 lower-bound -> specification-expr
700 // R818 upper-bound -> specification-expr
701 TYPE_PARSER(construct<ExplicitShapeSpec>(
702 maybe(specificationExpr / ":"), specificationExpr))
703
704 // R819 assumed-shape-spec -> [lower-bound] :
705 TYPE_PARSER(construct<AssumedShapeSpec>(maybe(specificationExpr) / ":"))
706
707 // R820 deferred-shape-spec -> :
708 // deferred-shape-spec-list - just a list of colons
709 TYPE_PARSER(construct<DeferredShapeSpecList>(
710 applyFunction(listLength, nonemptyList(":"_tok))))
711
712 // R821 assumed-implied-spec -> [lower-bound :] *
713 TYPE_PARSER(construct<AssumedImpliedSpec>(maybe(specificationExpr / ":") / "*"))
714
715 // R822 assumed-size-spec -> explicit-shape-spec-list , assumed-implied-spec
716 TYPE_PARSER(construct<AssumedSizeSpec>(
717 nonemptyList(explicitShapeSpec) / ",", assumedImpliedSpec))
718
719 // R823 implied-shape-or-assumed-size-spec -> assumed-implied-spec
720 // R824 implied-shape-spec -> assumed-implied-spec , assumed-implied-spec-list
721 // I.e., when the assumed-implied-spec-list has a single item, it constitutes an
722 // implied-shape-or-assumed-size-spec; otherwise, an implied-shape-spec.
TYPE_PARSER(construct<ImpliedShapeSpec> (nonemptyList (assumedImpliedSpec)))723 TYPE_PARSER(construct<ImpliedShapeSpec>(nonemptyList(assumedImpliedSpec)))
724
725 // R825 assumed-rank-spec -> ..
726 TYPE_PARSER(construct<AssumedRankSpec>(".."_tok))
727
728 // R826 intent-spec -> IN | OUT | INOUT
729 TYPE_PARSER(construct<IntentSpec>("IN OUT" >> pure(IntentSpec::Intent::InOut) ||
730 "IN" >> pure(IntentSpec::Intent::In) ||
731 "OUT" >> pure(IntentSpec::Intent::Out)))
732
733 // R827 access-stmt -> access-spec [[::] access-id-list]
734 TYPE_PARSER(construct<AccessStmt>(accessSpec,
735 defaulted(maybe("::"_tok) >>
736 nonemptyList("expected names and generic specifications"_err_en_US,
737 Parser<AccessId>{}))))
738
739 // R828 access-id -> access-name | generic-spec
740 TYPE_PARSER(construct<AccessId>(indirect(genericSpec)) ||
741 construct<AccessId>(name)) // initially ambiguous with genericSpec
742
743 // R829 allocatable-stmt -> ALLOCATABLE [::] allocatable-decl-list
744 TYPE_PARSER(construct<AllocatableStmt>("ALLOCATABLE" >> maybe("::"_tok) >>
745 nonemptyList(
746 "expected object declarations"_err_en_US, Parser<ObjectDecl>{})))
747
748 // R830 allocatable-decl ->
749 // object-name [( array-spec )] [lbracket coarray-spec rbracket]
750 // R860 target-decl ->
751 // object-name [( array-spec )] [lbracket coarray-spec rbracket]
752 TYPE_PARSER(
753 construct<ObjectDecl>(objectName, maybe(arraySpec), maybe(coarraySpec)))
754
755 // R831 asynchronous-stmt -> ASYNCHRONOUS [::] object-name-list
756 TYPE_PARSER(construct<AsynchronousStmt>("ASYNCHRONOUS" >> maybe("::"_tok) >>
757 nonemptyList("expected object names"_err_en_US, objectName)))
758
759 // R832 bind-stmt -> language-binding-spec [::] bind-entity-list
760 TYPE_PARSER(construct<BindStmt>(languageBindingSpec / maybe("::"_tok),
761 nonemptyList("expected bind entities"_err_en_US, Parser<BindEntity>{})))
762
763 // R833 bind-entity -> entity-name | / common-block-name /
764 TYPE_PARSER(construct<BindEntity>(pure(BindEntity::Kind::Object), name) ||
765 construct<BindEntity>("/" >> pure(BindEntity::Kind::Common), name / "/"))
766
767 // R834 codimension-stmt -> CODIMENSION [::] codimension-decl-list
768 TYPE_PARSER(construct<CodimensionStmt>("CODIMENSION" >> maybe("::"_tok) >>
769 nonemptyList("expected codimension declarations"_err_en_US,
770 Parser<CodimensionDecl>{})))
771
772 // R835 codimension-decl -> coarray-name lbracket coarray-spec rbracket
773 TYPE_PARSER(construct<CodimensionDecl>(name, coarraySpec))
774
775 // R836 contiguous-stmt -> CONTIGUOUS [::] object-name-list
776 TYPE_PARSER(construct<ContiguousStmt>("CONTIGUOUS" >> maybe("::"_tok) >>
777 nonemptyList("expected object names"_err_en_US, objectName)))
778
779 // R837 data-stmt -> DATA data-stmt-set [[,] data-stmt-set]...
780 TYPE_CONTEXT_PARSER("DATA statement"_en_US,
781 construct<DataStmt>(
782 "DATA" >> nonemptySeparated(Parser<DataStmtSet>{}, maybe(","_tok))))
783
784 // R838 data-stmt-set -> data-stmt-object-list / data-stmt-value-list /
785 TYPE_PARSER(construct<DataStmtSet>(
786 nonemptyList(
787 "expected DATA statement objects"_err_en_US, Parser<DataStmtObject>{}),
788 withMessage("expected DATA statement value list"_err_en_US,
789 "/"_tok >> nonemptyList("expected DATA statement values"_err_en_US,
790 Parser<DataStmtValue>{})) /
791 "/"))
792
793 // R839 data-stmt-object -> variable | data-implied-do
794 TYPE_PARSER(construct<DataStmtObject>(indirect(variable)) ||
795 construct<DataStmtObject>(dataImpliedDo))
796
797 // R840 data-implied-do ->
798 // ( data-i-do-object-list , [integer-type-spec ::] data-i-do-variable
799 // = scalar-int-constant-expr , scalar-int-constant-expr
800 // [, scalar-int-constant-expr] )
801 // R842 data-i-do-variable -> do-variable
802 TYPE_PARSER(parenthesized(construct<DataImpliedDo>(
803 nonemptyList(Parser<DataIDoObject>{} / lookAhead(","_tok)) / ",",
804 maybe(integerTypeSpec / "::"), loopBounds(scalarIntConstantExpr))))
805
806 // R841 data-i-do-object ->
807 // array-element | scalar-structure-component | data-implied-do
808 TYPE_PARSER(construct<DataIDoObject>(scalar(indirect(designator))) ||
809 construct<DataIDoObject>(indirect(dataImpliedDo)))
810
811 // R843 data-stmt-value -> [data-stmt-repeat *] data-stmt-constant
812 TYPE_PARSER(construct<DataStmtValue>(
813 maybe(Parser<DataStmtRepeat>{} / "*"), Parser<DataStmtConstant>{}))
814
815 // R847 constant-subobject -> designator
816 // R846 int-constant-subobject -> constant-subobject
817 constexpr auto constantSubobject{constant(indirect(designator))};
818
819 // R844 data-stmt-repeat -> scalar-int-constant | scalar-int-constant-subobject
820 // R607 int-constant -> constant
821 // Factored into: constant -> literal-constant -> int-literal-constant
822 // The named-constant alternative of constant is subsumed by constant-subobject
823 TYPE_PARSER(construct<DataStmtRepeat>(intLiteralConstant) ||
824 construct<DataStmtRepeat>(scalar(integer(constantSubobject))))
825
826 // R845 data-stmt-constant ->
827 // scalar-constant | scalar-constant-subobject |
828 // signed-int-literal-constant | signed-real-literal-constant |
829 // null-init | initial-data-target |
830 // constant-structure-constructor
831 // null-init and a structure-constructor without parameters or components
832 // are syntactically ambiguous in DATA, so "x()" is misparsed into a
833 // null-init then fixed up later in expression semantics.
834 // TODO: Some structure constructors can be misrecognized as array
835 // references into constant subobjects.
836 TYPE_PARSER(sourced(first(
837 construct<DataStmtConstant>(scalar(Parser<ConstantValue>{})),
838 construct<DataStmtConstant>(nullInit),
839 construct<DataStmtConstant>(scalar(constantSubobject)) / !"("_tok,
840 construct<DataStmtConstant>(Parser<StructureConstructor>{}),
841 construct<DataStmtConstant>(signedRealLiteralConstant),
842 construct<DataStmtConstant>(signedIntLiteralConstant),
843 extension<LanguageFeature::SignedComplexLiteral>(
844 construct<DataStmtConstant>(Parser<SignedComplexLiteralConstant>{})),
845 construct<DataStmtConstant>(initialDataTarget))))
846
847 // R848 dimension-stmt ->
848 // DIMENSION [::] array-name ( array-spec )
849 // [, array-name ( array-spec )]...
850 TYPE_CONTEXT_PARSER("DIMENSION statement"_en_US,
851 construct<DimensionStmt>("DIMENSION" >> maybe("::"_tok) >>
852 nonemptyList("expected array specifications"_err_en_US,
853 construct<DimensionStmt::Declaration>(name, arraySpec))))
854
855 // R849 intent-stmt -> INTENT ( intent-spec ) [::] dummy-arg-name-list
856 TYPE_CONTEXT_PARSER("INTENT statement"_en_US,
857 construct<IntentStmt>(
858 "INTENT" >> parenthesized(intentSpec) / maybe("::"_tok), listOfNames))
859
860 // R850 optional-stmt -> OPTIONAL [::] dummy-arg-name-list
861 TYPE_PARSER(
862 construct<OptionalStmt>("OPTIONAL" >> maybe("::"_tok) >> listOfNames))
863
864 // R851 parameter-stmt -> PARAMETER ( named-constant-def-list )
865 // Legacy extension: omitted parentheses, no implicit typing from names
866 TYPE_CONTEXT_PARSER("PARAMETER statement"_en_US,
867 construct<ParameterStmt>(
868 "PARAMETER" >> parenthesized(nonemptyList(Parser<NamedConstantDef>{}))))
869 TYPE_CONTEXT_PARSER("old style PARAMETER statement"_en_US,
870 extension<LanguageFeature::OldStyleParameter>(construct<OldParameterStmt>(
871 "PARAMETER" >> nonemptyList(Parser<NamedConstantDef>{}))))
872
873 // R852 named-constant-def -> named-constant = constant-expr
874 TYPE_PARSER(construct<NamedConstantDef>(namedConstant, "=" >> constantExpr))
875
876 // R853 pointer-stmt -> POINTER [::] pointer-decl-list
877 TYPE_PARSER(construct<PointerStmt>("POINTER" >> maybe("::"_tok) >>
878 nonemptyList(
879 "expected pointer declarations"_err_en_US, Parser<PointerDecl>{})))
880
881 // R854 pointer-decl ->
882 // object-name [( deferred-shape-spec-list )] | proc-entity-name
TYPE_PARSER(construct<PointerDecl> (name,maybe (parenthesized (deferredShapeSpecList))))883 TYPE_PARSER(
884 construct<PointerDecl>(name, maybe(parenthesized(deferredShapeSpecList))))
885
886 // R855 protected-stmt -> PROTECTED [::] entity-name-list
887 TYPE_PARSER(
888 construct<ProtectedStmt>("PROTECTED" >> maybe("::"_tok) >> listOfNames))
889
890 // R856 save-stmt -> SAVE [[::] saved-entity-list]
891 TYPE_PARSER(construct<SaveStmt>(
892 "SAVE" >> defaulted(maybe("::"_tok) >>
893 nonemptyList("expected SAVE entities"_err_en_US,
894 Parser<SavedEntity>{}))))
895
896 // R857 saved-entity -> object-name | proc-pointer-name | / common-block-name /
897 // R858 proc-pointer-name -> name
898 TYPE_PARSER(construct<SavedEntity>(pure(SavedEntity::Kind::Entity), name) ||
899 construct<SavedEntity>("/" >> pure(SavedEntity::Kind::Common), name / "/"))
900
901 // R859 target-stmt -> TARGET [::] target-decl-list
902 TYPE_PARSER(construct<TargetStmt>("TARGET" >> maybe("::"_tok) >>
903 nonemptyList("expected objects"_err_en_US, Parser<ObjectDecl>{})))
904
905 // R861 value-stmt -> VALUE [::] dummy-arg-name-list
906 TYPE_PARSER(construct<ValueStmt>("VALUE" >> maybe("::"_tok) >> listOfNames))
907
908 // R862 volatile-stmt -> VOLATILE [::] object-name-list
909 TYPE_PARSER(construct<VolatileStmt>("VOLATILE" >> maybe("::"_tok) >>
910 nonemptyList("expected object names"_err_en_US, objectName)))
911
912 // R866 implicit-name-spec -> EXTERNAL | TYPE
913 constexpr auto implicitNameSpec{
914 "EXTERNAL" >> pure(ImplicitStmt::ImplicitNoneNameSpec::External) ||
915 "TYPE" >> pure(ImplicitStmt::ImplicitNoneNameSpec::Type)};
916
917 // R863 implicit-stmt ->
918 // IMPLICIT implicit-spec-list |
919 // IMPLICIT NONE [( [implicit-name-spec-list] )]
920 TYPE_CONTEXT_PARSER("IMPLICIT statement"_en_US,
921 construct<ImplicitStmt>(
922 "IMPLICIT" >> nonemptyList("expected IMPLICIT specifications"_err_en_US,
923 Parser<ImplicitSpec>{})) ||
924 construct<ImplicitStmt>("IMPLICIT NONE"_sptok >>
925 defaulted(parenthesized(optionalList(implicitNameSpec)))))
926
927 // R864 implicit-spec -> declaration-type-spec ( letter-spec-list )
928 // The variant form of declarationTypeSpec is meant to avoid misrecognition
929 // of a letter-spec as a simple parenthesized expression for kind or character
930 // length, e.g., PARAMETER(I=5,N=1); IMPLICIT REAL(I-N)(O-Z) vs.
931 // IMPLICIT REAL(I-N). The variant form needs to attempt to reparse only
932 // types with optional parenthesized kind/length expressions, so derived
933 // type specs, DOUBLE PRECISION, and DOUBLE COMPLEX need not be considered.
934 constexpr auto noKindSelector{construct<std::optional<KindSelector>>()};
935 constexpr auto implicitSpecDeclarationTypeSpecRetry{
936 construct<DeclarationTypeSpec>(first(
937 construct<IntrinsicTypeSpec>(
938 construct<IntegerTypeSpec>("INTEGER" >> noKindSelector)),
939 construct<IntrinsicTypeSpec>(
940 construct<IntrinsicTypeSpec::Real>("REAL" >> noKindSelector)),
941 construct<IntrinsicTypeSpec>(
942 construct<IntrinsicTypeSpec::Complex>("COMPLEX" >> noKindSelector)),
943 construct<IntrinsicTypeSpec>(construct<IntrinsicTypeSpec::Character>(
944 "CHARACTER" >> construct<std::optional<CharSelector>>())),
945 construct<IntrinsicTypeSpec>(construct<IntrinsicTypeSpec::Logical>(
946 "LOGICAL" >> noKindSelector))))};
947
948 TYPE_PARSER(construct<ImplicitSpec>(declarationTypeSpec,
949 parenthesized(nonemptyList(Parser<LetterSpec>{}))) ||
950 construct<ImplicitSpec>(implicitSpecDeclarationTypeSpecRetry,
951 parenthesized(nonemptyList(Parser<LetterSpec>{}))))
952
953 // R865 letter-spec -> letter [- letter]
954 TYPE_PARSER(space >> (construct<LetterSpec>(letter, maybe("-" >> letter)) ||
955 construct<LetterSpec>(otherIdChar,
956 construct<std::optional<const char *>>())))
957
958 // R867 import-stmt ->
959 // IMPORT [[::] import-name-list] |
960 // IMPORT , ONLY : import-name-list | IMPORT , NONE | IMPORT , ALL
961 TYPE_CONTEXT_PARSER("IMPORT statement"_en_US,
962 construct<ImportStmt>(
963 "IMPORT , ONLY :" >> pure(common::ImportKind::Only), listOfNames) ||
964 construct<ImportStmt>(
965 "IMPORT , NONE" >> pure(common::ImportKind::None)) ||
966 construct<ImportStmt>(
967 "IMPORT , ALL" >> pure(common::ImportKind::All)) ||
968 construct<ImportStmt>(
969 "IMPORT" >> maybe("::"_tok) >> optionalList(name)))
970
971 // R868 namelist-stmt ->
972 // NAMELIST / namelist-group-name / namelist-group-object-list
973 // [[,] / namelist-group-name / namelist-group-object-list]...
974 // R869 namelist-group-object -> variable-name
975 TYPE_PARSER(construct<NamelistStmt>("NAMELIST" >>
976 nonemptySeparated(
977 construct<NamelistStmt::Group>("/" >> name / "/", listOfNames),
978 maybe(","_tok))))
979
980 // R870 equivalence-stmt -> EQUIVALENCE equivalence-set-list
981 // R871 equivalence-set -> ( equivalence-object , equivalence-object-list )
982 TYPE_PARSER(construct<EquivalenceStmt>("EQUIVALENCE" >>
983 nonemptyList(
984 parenthesized(nonemptyList("expected EQUIVALENCE objects"_err_en_US,
985 Parser<EquivalenceObject>{})))))
986
987 // R872 equivalence-object -> variable-name | array-element | substring
TYPE_PARSER(construct<EquivalenceObject> (indirect (designator)))988 TYPE_PARSER(construct<EquivalenceObject>(indirect(designator)))
989
990 // R873 common-stmt ->
991 // COMMON [/ [common-block-name] /] common-block-object-list
992 // [[,] / [common-block-name] / common-block-object-list]...
993 TYPE_PARSER(
994 construct<CommonStmt>("COMMON" >> defaulted("/" >> maybe(name) / "/"),
995 nonemptyList("expected COMMON block objects"_err_en_US,
996 Parser<CommonBlockObject>{}),
997 many(maybe(","_tok) >>
998 construct<CommonStmt::Block>("/" >> maybe(name) / "/",
999 nonemptyList("expected COMMON block objects"_err_en_US,
1000 Parser<CommonBlockObject>{})))))
1001
1002 // R874 common-block-object -> variable-name [( array-spec )]
1003 TYPE_PARSER(construct<CommonBlockObject>(name, maybe(arraySpec)))
1004
1005 // R901 designator -> object-name | array-element | array-section |
1006 // coindexed-named-object | complex-part-designator |
1007 // structure-component | substring
1008 // The Standard's productions for designator and its alternatives are
1009 // ambiguous without recourse to a symbol table. Many of the alternatives
1010 // for designator (viz., array-element, coindexed-named-object,
1011 // and structure-component) are all syntactically just data-ref.
1012 // What designator boils down to is this:
1013 // It starts with either a name or a character literal.
1014 // If it starts with a character literal, it must be a substring.
1015 // If it starts with a name, it's a sequence of %-separated parts;
1016 // each part is a name, maybe a (section-subscript-list), and
1017 // maybe an [image-selector].
1018 // If it's a substring, it ends with (substring-range).
1019 TYPE_CONTEXT_PARSER("designator"_en_US,
1020 sourced(construct<Designator>(substring) || construct<Designator>(dataRef)))
1021
1022 constexpr auto percentOrDot{"%"_tok ||
1023 // legacy VAX extension for RECORD field access
1024 extension<LanguageFeature::DECStructures>(
1025 "."_tok / lookAhead(OldStructureComponentName{}))};
1026
1027 // R902 variable -> designator | function-reference
1028 // This production appears to be left-recursive in the grammar via
1029 // function-reference -> procedure-designator -> proc-component-ref ->
1030 // scalar-variable
1031 // and would be so if we were to allow functions to be called via procedure
1032 // pointer components within derived type results of other function references
1033 // (a reasonable extension, esp. in the case of procedure pointer components
1034 // that are NOPASS). However, Fortran constrains the use of a variable in a
1035 // proc-component-ref to be a data-ref without coindices (C1027).
1036 // Some array element references will be misrecognized as function references.
1037 constexpr auto noMoreAddressing{!"("_tok >> !"["_tok >> !percentOrDot};
1038 TYPE_CONTEXT_PARSER("variable"_en_US,
1039 construct<Variable>(indirect(functionReference / noMoreAddressing)) ||
1040 construct<Variable>(indirect(designator)))
1041
1042 // R908 substring -> parent-string ( substring-range )
1043 // R909 parent-string ->
1044 // scalar-variable-name | array-element | coindexed-named-object |
1045 // scalar-structure-component | scalar-char-literal-constant |
1046 // scalar-named-constant
TYPE_PARSER(construct<Substring> (dataRef,parenthesized (Parser<SubstringRange>{})))1047 TYPE_PARSER(
1048 construct<Substring>(dataRef, parenthesized(Parser<SubstringRange>{})))
1049
1050 TYPE_PARSER(construct<CharLiteralConstantSubstring>(
1051 charLiteralConstant, parenthesized(Parser<SubstringRange>{})))
1052
1053 // R910 substring-range -> [scalar-int-expr] : [scalar-int-expr]
1054 TYPE_PARSER(construct<SubstringRange>(
1055 maybe(scalarIntExpr), ":" >> maybe(scalarIntExpr)))
1056
1057 // R911 data-ref -> part-ref [% part-ref]...
1058 // R914 coindexed-named-object -> data-ref
1059 // R917 array-element -> data-ref
1060 TYPE_PARSER(
1061 construct<DataRef>(nonemptySeparated(Parser<PartRef>{}, percentOrDot)))
1062
1063 // R912 part-ref -> part-name [( section-subscript-list )] [image-selector]
1064 TYPE_PARSER(construct<PartRef>(name,
1065 defaulted(
1066 parenthesized(nonemptyList(Parser<SectionSubscript>{})) / !"=>"_tok),
1067 maybe(Parser<ImageSelector>{})))
1068
1069 // R913 structure-component -> data-ref
1070 TYPE_PARSER(construct<StructureComponent>(
1071 construct<DataRef>(some(Parser<PartRef>{} / percentOrDot)), name))
1072
1073 // R919 subscript -> scalar-int-expr
1074 constexpr auto subscript{scalarIntExpr};
1075
1076 // R920 section-subscript -> subscript | subscript-triplet | vector-subscript
1077 // R923 vector-subscript -> int-expr
1078 // N.B. The distinction that needs to be made between "subscript" and
1079 // "vector-subscript" is deferred to semantic analysis.
1080 TYPE_PARSER(construct<SectionSubscript>(Parser<SubscriptTriplet>{}) ||
1081 construct<SectionSubscript>(intExpr))
1082
1083 // R921 subscript-triplet -> [subscript] : [subscript] [: stride]
1084 TYPE_PARSER(construct<SubscriptTriplet>(
1085 maybe(subscript), ":" >> maybe(subscript), maybe(":" >> subscript)))
1086
1087 // R925 cosubscript -> scalar-int-expr
1088 constexpr auto cosubscript{scalarIntExpr};
1089
1090 // R924 image-selector ->
1091 // lbracket cosubscript-list [, image-selector-spec-list] rbracket
1092 TYPE_CONTEXT_PARSER("image selector"_en_US,
1093 construct<ImageSelector>("[" >> nonemptyList(cosubscript / !"="_tok),
1094 defaulted("," >> nonemptyList(Parser<ImageSelectorSpec>{})) / "]"))
1095
1096 // R926 image-selector-spec ->
1097 // STAT = stat-variable | TEAM = team-value |
1098 // TEAM_NUMBER = scalar-int-expr
1099 TYPE_PARSER(construct<ImageSelectorSpec>(construct<ImageSelectorSpec::Stat>(
1100 "STAT =" >> scalar(integer(indirect(variable))))) ||
1101 construct<ImageSelectorSpec>(construct<TeamValue>("TEAM =" >> teamValue)) ||
1102 construct<ImageSelectorSpec>(construct<ImageSelectorSpec::Team_Number>(
1103 "TEAM_NUMBER =" >> scalarIntExpr)))
1104
1105 // R927 allocate-stmt ->
1106 // ALLOCATE ( [type-spec ::] allocation-list [, alloc-opt-list] )
1107 TYPE_CONTEXT_PARSER("ALLOCATE statement"_en_US,
1108 construct<AllocateStmt>("ALLOCATE (" >> maybe(typeSpec / "::"),
1109 nonemptyList(Parser<Allocation>{}),
1110 defaulted("," >> nonemptyList(Parser<AllocOpt>{})) / ")"))
1111
1112 // R928 alloc-opt ->
1113 // ERRMSG = errmsg-variable | MOLD = source-expr |
1114 // SOURCE = source-expr | STAT = stat-variable
1115 // R931 source-expr -> expr
1116 TYPE_PARSER(construct<AllocOpt>(
1117 construct<AllocOpt::Mold>("MOLD =" >> indirect(expr))) ||
1118 construct<AllocOpt>(
1119 construct<AllocOpt::Source>("SOURCE =" >> indirect(expr))) ||
1120 construct<AllocOpt>(statOrErrmsg))
1121
1122 // R929 stat-variable -> scalar-int-variable
TYPE_PARSER(construct<StatVariable> (scalar (integer (variable))))1123 TYPE_PARSER(construct<StatVariable>(scalar(integer(variable))))
1124
1125 // R932 allocation ->
1126 // allocate-object [( allocate-shape-spec-list )]
1127 // [lbracket allocate-coarray-spec rbracket]
1128 // TODO: allocate-shape-spec-list might be misrecognized as
1129 // the final list of subscripts in allocate-object.
1130 TYPE_PARSER(construct<Allocation>(Parser<AllocateObject>{},
1131 defaulted(parenthesized(nonemptyList(Parser<AllocateShapeSpec>{}))),
1132 maybe(bracketed(Parser<AllocateCoarraySpec>{}))))
1133
1134 // R933 allocate-object -> variable-name | structure-component
1135 TYPE_PARSER(construct<AllocateObject>(structureComponent) ||
1136 construct<AllocateObject>(name / !"="_tok))
1137
1138 // R934 allocate-shape-spec -> [lower-bound-expr :] upper-bound-expr
1139 // R938 allocate-coshape-spec -> [lower-bound-expr :] upper-bound-expr
1140 TYPE_PARSER(construct<AllocateShapeSpec>(maybe(boundExpr / ":"), boundExpr))
1141
1142 // R937 allocate-coarray-spec ->
1143 // [allocate-coshape-spec-list ,] [lower-bound-expr :] *
1144 TYPE_PARSER(construct<AllocateCoarraySpec>(
1145 defaulted(nonemptyList(Parser<AllocateShapeSpec>{}) / ","),
1146 maybe(boundExpr / ":") / "*"))
1147
1148 // R939 nullify-stmt -> NULLIFY ( pointer-object-list )
1149 TYPE_CONTEXT_PARSER("NULLIFY statement"_en_US,
1150 "NULLIFY" >> parenthesized(construct<NullifyStmt>(
1151 nonemptyList(Parser<PointerObject>{}))))
1152
1153 // R940 pointer-object ->
1154 // variable-name | structure-component | proc-pointer-name
1155 TYPE_PARSER(construct<PointerObject>(structureComponent) ||
1156 construct<PointerObject>(name))
1157
1158 // R941 deallocate-stmt ->
1159 // DEALLOCATE ( allocate-object-list [, dealloc-opt-list] )
1160 TYPE_CONTEXT_PARSER("DEALLOCATE statement"_en_US,
1161 construct<DeallocateStmt>(
1162 "DEALLOCATE (" >> nonemptyList(Parser<AllocateObject>{}),
1163 defaulted("," >> nonemptyList(statOrErrmsg)) / ")"))
1164
1165 // R942 dealloc-opt -> STAT = stat-variable | ERRMSG = errmsg-variable
1166 // R1165 sync-stat -> STAT = stat-variable | ERRMSG = errmsg-variable
1167 TYPE_PARSER(construct<StatOrErrmsg>("STAT =" >> statVariable) ||
1168 construct<StatOrErrmsg>("ERRMSG =" >> msgVariable))
1169
1170 // Directives, extensions, and deprecated statements
1171 // !DIR$ IGNORE_TKR [ [(tkr...)] name ]...
1172 // !DIR$ name...
1173 constexpr auto beginDirective{skipStuffBeforeStatement >> "!"_ch};
1174 constexpr auto endDirective{space >> endOfLine};
1175 constexpr auto ignore_tkr{
1176 "DIR$ IGNORE_TKR" >> optionalList(construct<CompilerDirective::IgnoreTKR>(
1177 defaulted(parenthesized(some("tkr"_ch))), name))};
1178 TYPE_PARSER(beginDirective >>
1179 sourced(construct<CompilerDirective>(ignore_tkr) ||
1180 construct<CompilerDirective>(
1181 "DIR$" >> many(construct<CompilerDirective::NameValue>(name,
1182 maybe(("="_tok || ":"_tok) >> digitString64))))) /
1183 endDirective)
1184
1185 TYPE_PARSER(extension<LanguageFeature::CrayPointer>(construct<BasedPointerStmt>(
1186 "POINTER" >> nonemptyList("expected POINTER associations"_err_en_US,
1187 construct<BasedPointer>("(" >> objectName / ",",
1188 objectName, maybe(Parser<ArraySpec>{}) / ")")))))
1189
1190 TYPE_PARSER(construct<StructureStmt>("STRUCTURE /" >> name / "/", pure(true),
1191 optionalList(entityDecl)) ||
1192 construct<StructureStmt>(
1193 "STRUCTURE" >> name, pure(false), pure<std::list<EntityDecl>>()))
1194
1195 TYPE_PARSER(construct<StructureField>(statement(StructureComponents{})) ||
1196 construct<StructureField>(indirect(Parser<Union>{})) ||
1197 construct<StructureField>(indirect(Parser<StructureDef>{})))
1198
1199 TYPE_CONTEXT_PARSER("STRUCTURE definition"_en_US,
1200 extension<LanguageFeature::DECStructures>(construct<StructureDef>(
1201 statement(Parser<StructureStmt>{}), many(Parser<StructureField>{}),
1202 statement(
1203 construct<StructureDef::EndStructureStmt>("END STRUCTURE"_tok)))))
1204
1205 TYPE_CONTEXT_PARSER("UNION definition"_en_US,
1206 construct<Union>(statement(construct<Union::UnionStmt>("UNION"_tok)),
1207 many(Parser<Map>{}),
1208 statement(construct<Union::EndUnionStmt>("END UNION"_tok))))
1209
1210 TYPE_CONTEXT_PARSER("MAP definition"_en_US,
1211 construct<Map>(statement(construct<Map::MapStmt>("MAP"_tok)),
1212 many(Parser<StructureField>{}),
1213 statement(construct<Map::EndMapStmt>("END MAP"_tok))))
1214
1215 TYPE_CONTEXT_PARSER("arithmetic IF statement"_en_US,
1216 deprecated<LanguageFeature::ArithmeticIF>(construct<ArithmeticIfStmt>(
1217 "IF" >> parenthesized(expr), label / ",", label / ",", label)))
1218
1219 TYPE_CONTEXT_PARSER("ASSIGN statement"_en_US,
1220 deprecated<LanguageFeature::Assign>(
1221 construct<AssignStmt>("ASSIGN" >> label, "TO" >> name)))
1222
1223 TYPE_CONTEXT_PARSER("assigned GOTO statement"_en_US,
1224 deprecated<LanguageFeature::AssignedGOTO>(construct<AssignedGotoStmt>(
1225 "GO TO" >> name,
1226 defaulted(maybe(","_tok) >>
1227 parenthesized(nonemptyList("expected labels"_err_en_US, label))))))
1228
1229 TYPE_CONTEXT_PARSER("PAUSE statement"_en_US,
1230 deprecated<LanguageFeature::Pause>(
1231 construct<PauseStmt>("PAUSE" >> maybe(Parser<StopCode>{}))))
1232
1233 // These requirement productions are defined by the Fortran standard but never
1234 // used directly by the grammar:
1235 // R620 delimiter -> ( | ) | / | [ | ] | (/ | /)
1236 // R1027 numeric-expr -> expr
1237 // R1031 int-constant-expr -> int-expr
1238 // R1221 dtv-type-spec -> TYPE ( derived-type-spec ) |
1239 // CLASS ( derived-type-spec )
1240 //
1241 // These requirement productions are defined and used, but need not be
1242 // defined independently here in this file:
1243 // R771 lbracket -> [
1244 // R772 rbracket -> ]
1245 //
1246 // Further note that:
1247 // R607 int-constant -> constant
1248 // is used only once via R844 scalar-int-constant
1249 // R904 logical-variable -> variable
1250 // is used only via scalar-logical-variable
1251 // R906 default-char-variable -> variable
1252 // is used only via scalar-default-char-variable
1253 // R907 int-variable -> variable
1254 // is used only via scalar-int-variable
1255 // R915 complex-part-designator -> designator % RE | designator % IM
1256 // %RE and %IM are initially recognized as structure components
1257 // R916 type-param-inquiry -> designator % type-param-name
1258 // is occulted by structure component designators
1259 // R918 array-section ->
1260 // data-ref [( substring-range )] | complex-part-designator
1261 // is not used because parsing is not sensitive to rank
1262 // R1030 default-char-constant-expr -> default-char-expr
1263 // is only used via scalar-default-char-constant-expr
1264 } // namespace Fortran::parser
1265