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 // R608 intrinsic-operator -> 51 // power-op | mult-op | add-op | concat-op | rel-op | 52 // not-op | and-op | or-op | equiv-op 53 // R610 extended-intrinsic-op -> intrinsic-operator 54 // These parsers must be ordered carefully to avoid misrecognition. 55 constexpr auto namedIntrinsicOperator{ 56 ".LT." >> pure(DefinedOperator::IntrinsicOperator::LT) || 57 ".LE." >> pure(DefinedOperator::IntrinsicOperator::LE) || 58 ".EQ." >> pure(DefinedOperator::IntrinsicOperator::EQ) || 59 ".NE." >> pure(DefinedOperator::IntrinsicOperator::NE) || 60 ".GE." >> pure(DefinedOperator::IntrinsicOperator::GE) || 61 ".GT." >> pure(DefinedOperator::IntrinsicOperator::GT) || 62 ".NOT." >> pure(DefinedOperator::IntrinsicOperator::NOT) || 63 ".AND." >> pure(DefinedOperator::IntrinsicOperator::AND) || 64 ".OR." >> pure(DefinedOperator::IntrinsicOperator::OR) || 65 ".EQV." >> pure(DefinedOperator::IntrinsicOperator::EQV) || 66 ".NEQV." >> pure(DefinedOperator::IntrinsicOperator::NEQV) || 67 extension<LanguageFeature::XOROperator>( 68 "nonstandard usage: .XOR. spelling of .NEQV."_port_en_US, 69 ".XOR." >> pure(DefinedOperator::IntrinsicOperator::NEQV)) || 70 extension<LanguageFeature::LogicalAbbreviations>( 71 "nonstandard usage: abbreviated logical operator"_port_en_US, 72 ".N." >> pure(DefinedOperator::IntrinsicOperator::NOT) || 73 ".A." >> pure(DefinedOperator::IntrinsicOperator::AND) || 74 ".O." >> pure(DefinedOperator::IntrinsicOperator::OR) || 75 extension<LanguageFeature::XOROperator>( 76 "nonstandard usage: .X. spelling of .NEQV."_port_en_US, 77 ".X." >> pure(DefinedOperator::IntrinsicOperator::NEQV)))}; 78 79 constexpr auto intrinsicOperator{ 80 "**" >> pure(DefinedOperator::IntrinsicOperator::Power) || 81 "*" >> pure(DefinedOperator::IntrinsicOperator::Multiply) || 82 "//" >> pure(DefinedOperator::IntrinsicOperator::Concat) || 83 "/=" >> pure(DefinedOperator::IntrinsicOperator::NE) || 84 "/" >> pure(DefinedOperator::IntrinsicOperator::Divide) || 85 "+" >> pure(DefinedOperator::IntrinsicOperator::Add) || 86 "-" >> pure(DefinedOperator::IntrinsicOperator::Subtract) || 87 "<=" >> pure(DefinedOperator::IntrinsicOperator::LE) || 88 extension<LanguageFeature::AlternativeNE>( 89 "nonstandard usage: <> spelling of /= or .NE."_port_en_US, 90 "<>" >> pure(DefinedOperator::IntrinsicOperator::NE)) || 91 "<" >> pure(DefinedOperator::IntrinsicOperator::LT) || 92 "==" >> pure(DefinedOperator::IntrinsicOperator::EQ) || 93 ">=" >> pure(DefinedOperator::IntrinsicOperator::GE) || 94 ">" >> pure(DefinedOperator::IntrinsicOperator::GT) || 95 namedIntrinsicOperator}; 96 97 // R609 defined-operator -> 98 // defined-unary-op | defined-binary-op | extended-intrinsic-op 99 TYPE_PARSER(construct<DefinedOperator>(intrinsicOperator) || 100 construct<DefinedOperator>(definedOpName)) 101 102 // R505 implicit-part -> [implicit-part-stmt]... implicit-stmt 103 // N.B. PARAMETER, FORMAT, & ENTRY statements that appear before any 104 // other kind of declaration-construct will be parsed into the 105 // implicit-part. 106 TYPE_CONTEXT_PARSER("implicit part"_en_US, 107 construct<ImplicitPart>(many(Parser<ImplicitPartStmt>{}))) 108 109 // R506 implicit-part-stmt -> 110 // implicit-stmt | parameter-stmt | format-stmt | entry-stmt 111 TYPE_PARSER(first( 112 construct<ImplicitPartStmt>(statement(indirect(Parser<ImplicitStmt>{}))), 113 construct<ImplicitPartStmt>(statement(indirect(parameterStmt))), 114 construct<ImplicitPartStmt>(statement(indirect(oldParameterStmt))), 115 construct<ImplicitPartStmt>(statement(indirect(formatStmt))), 116 construct<ImplicitPartStmt>(statement(indirect(entryStmt))), 117 construct<ImplicitPartStmt>(indirect(compilerDirective)))) 118 119 // R512 internal-subprogram -> function-subprogram | subroutine-subprogram 120 // Internal subprograms are not program units, so their END statements 121 // can be followed by ';' and another statement on the same line. 122 TYPE_CONTEXT_PARSER("internal subprogram"_en_US, 123 (construct<InternalSubprogram>(indirect(functionSubprogram)) || 124 construct<InternalSubprogram>(indirect(subroutineSubprogram))) / 125 forceEndOfStmt) 126 127 // R511 internal-subprogram-part -> contains-stmt [internal-subprogram]... 128 TYPE_CONTEXT_PARSER("internal subprogram part"_en_US, 129 construct<InternalSubprogramPart>(statement(containsStmt), 130 many(StartNewSubprogram{} >> Parser<InternalSubprogram>{}))) 131 132 // R605 literal-constant -> 133 // int-literal-constant | real-literal-constant | 134 // complex-literal-constant | logical-literal-constant | 135 // char-literal-constant | boz-literal-constant 136 TYPE_PARSER( 137 first(construct<LiteralConstant>(Parser<HollerithLiteralConstant>{}), 138 construct<LiteralConstant>(realLiteralConstant), 139 construct<LiteralConstant>(intLiteralConstant), 140 construct<LiteralConstant>(Parser<ComplexLiteralConstant>{}), 141 construct<LiteralConstant>(Parser<BOZLiteralConstant>{}), 142 construct<LiteralConstant>(charLiteralConstant), 143 construct<LiteralConstant>(Parser<LogicalLiteralConstant>{}))) 144 145 // R606 named-constant -> name 146 TYPE_PARSER(construct<NamedConstant>(name)) 147 148 // R701 type-param-value -> scalar-int-expr | * | : 149 TYPE_PARSER(construct<TypeParamValue>(scalarIntExpr) || 150 construct<TypeParamValue>(star) || 151 construct<TypeParamValue>(construct<TypeParamValue::Deferred>(":"_tok))) 152 153 // R702 type-spec -> intrinsic-type-spec | derived-type-spec 154 // N.B. This type-spec production is one of two instances in the Fortran 155 // grammar where intrinsic types and bare derived type names can clash; 156 // the other is below in R703 declaration-type-spec. Look-ahead is required 157 // to disambiguate the cases where a derived type name begins with the name 158 // of an intrinsic type, e.g., REALITY. 159 TYPE_CONTEXT_PARSER("type spec"_en_US, 160 construct<TypeSpec>(intrinsicTypeSpec / lookAhead("::"_tok || ")"_tok)) || 161 construct<TypeSpec>(derivedTypeSpec)) 162 163 // R703 declaration-type-spec -> 164 // intrinsic-type-spec | TYPE ( intrinsic-type-spec ) | 165 // TYPE ( derived-type-spec ) | CLASS ( derived-type-spec ) | 166 // CLASS ( * ) | TYPE ( * ) 167 // N.B. It is critical to distribute "parenthesized()" over the alternatives 168 // for TYPE (...), rather than putting the alternatives within it, which 169 // would fail on "TYPE(real_derived)" with a misrecognition of "real" as an 170 // intrinsic-type-spec. 171 // N.B. TYPE(x) is a derived type if x is a one-word extension intrinsic 172 // type (BYTE or DOUBLECOMPLEX), not the extension intrinsic type. 173 TYPE_CONTEXT_PARSER("declaration type spec"_en_US, 174 construct<DeclarationTypeSpec>(intrinsicTypeSpec) || 175 "TYPE" >> 176 (parenthesized(construct<DeclarationTypeSpec>( 177 !"DOUBLECOMPLEX"_tok >> !"BYTE"_tok >> 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 "nonstandard usage: STRUCTURE"_port_en_US, 189 construct<DeclarationTypeSpec>( 190 // As is also done for the STRUCTURE statement, the name of 191 // the structure includes the surrounding slashes to avoid 192 // name clashes. 193 construct<DeclarationTypeSpec::Record>( 194 "RECORD" >> sourced("/" >> name / "/"))))) 195 196 // R704 intrinsic-type-spec -> 197 // integer-type-spec | REAL [kind-selector] | DOUBLE PRECISION | 198 // COMPLEX [kind-selector] | CHARACTER [char-selector] | 199 // LOGICAL [kind-selector] 200 // Extensions: DOUBLE COMPLEX, BYTE 201 TYPE_CONTEXT_PARSER("intrinsic type spec"_en_US, 202 first(construct<IntrinsicTypeSpec>(integerTypeSpec), 203 construct<IntrinsicTypeSpec>( 204 construct<IntrinsicTypeSpec::Real>("REAL" >> maybe(kindSelector))), 205 construct<IntrinsicTypeSpec>("DOUBLE PRECISION" >> 206 construct<IntrinsicTypeSpec::DoublePrecision>()), 207 construct<IntrinsicTypeSpec>(construct<IntrinsicTypeSpec::Complex>( 208 "COMPLEX" >> maybe(kindSelector))), 209 construct<IntrinsicTypeSpec>(construct<IntrinsicTypeSpec::Character>( 210 "CHARACTER" >> maybe(Parser<CharSelector>{}))), 211 construct<IntrinsicTypeSpec>(construct<IntrinsicTypeSpec::Logical>( 212 "LOGICAL" >> maybe(kindSelector))), 213 extension<LanguageFeature::DoubleComplex>( 214 "nonstandard usage: DOUBLE COMPLEX"_port_en_US, 215 construct<IntrinsicTypeSpec>("DOUBLE COMPLEX"_sptok >> 216 construct<IntrinsicTypeSpec::DoubleComplex>())), 217 extension<LanguageFeature::Byte>("nonstandard usage: BYTE"_port_en_US, 218 construct<IntrinsicTypeSpec>(construct<IntegerTypeSpec>( 219 "BYTE" >> construct<std::optional<KindSelector>>(pure(1))))))) 220 221 // R705 integer-type-spec -> INTEGER [kind-selector] 222 TYPE_PARSER(construct<IntegerTypeSpec>("INTEGER" >> maybe(kindSelector))) 223 224 // R706 kind-selector -> ( [KIND =] scalar-int-constant-expr ) 225 // Legacy extension: kind-selector -> * digit-string 226 TYPE_PARSER(construct<KindSelector>( 227 parenthesized(maybe("KIND ="_tok) >> scalarIntConstantExpr)) || 228 extension<LanguageFeature::StarKind>( 229 "nonstandard usage: TYPE*KIND syntax"_port_en_US, 230 construct<KindSelector>(construct<KindSelector::StarSize>( 231 "*" >> digitString64 / spaceCheck)))) 232 233 // R707 signed-int-literal-constant -> [sign] int-literal-constant 234 TYPE_PARSER(sourced(construct<SignedIntLiteralConstant>( 235 SignedIntLiteralConstantWithoutKind{}, maybe(underscore >> kindParam)))) 236 237 // R708 int-literal-constant -> digit-string [_ kind-param] 238 // The negated look-ahead for a trailing underscore prevents misrecognition 239 // when the digit string is a numeric kind parameter of a character literal. 240 TYPE_PARSER(construct<IntLiteralConstant>( 241 space >> digitString, maybe(underscore >> kindParam) / !underscore)) 242 243 // R709 kind-param -> digit-string | scalar-int-constant-name 244 TYPE_PARSER(construct<KindParam>(digitString64) || 245 construct<KindParam>(scalar(integer(constant(name))))) 246 247 // R712 sign -> + | - 248 // N.B. A sign constitutes a whole token, so a space is allowed in free form 249 // after the sign and before a real-literal-constant or 250 // complex-literal-constant. A sign is not a unary operator in these contexts. 251 constexpr auto sign{ 252 "+"_tok >> pure(Sign::Positive) || "-"_tok >> pure(Sign::Negative)}; 253 254 // R713 signed-real-literal-constant -> [sign] real-literal-constant 255 constexpr auto signedRealLiteralConstant{ 256 construct<SignedRealLiteralConstant>(maybe(sign), realLiteralConstant)}; 257 258 // R714 real-literal-constant -> 259 // significand [exponent-letter exponent] [_ kind-param] | 260 // digit-string exponent-letter exponent [_ kind-param] 261 // R715 significand -> digit-string . [digit-string] | . digit-string 262 // R716 exponent-letter -> E | D 263 // Extension: Q 264 // R717 exponent -> signed-digit-string 265 constexpr auto exponentPart{ 266 ("ed"_ch || 267 extension<LanguageFeature::QuadPrecision>( 268 "nonstandard usage: Q exponent"_port_en_US, "q"_ch)) >> 269 SignedDigitString{}}; 270 271 TYPE_CONTEXT_PARSER("REAL literal constant"_en_US, 272 space >> 273 construct<RealLiteralConstant>( 274 sourced((digitString >> "."_ch >> 275 !(some(letter) >> 276 "."_ch /* don't misinterpret 1.AND. */) >> 277 maybe(digitString) >> maybe(exponentPart) >> ok || 278 "."_ch >> digitString >> maybe(exponentPart) >> ok || 279 digitString >> exponentPart >> ok) >> 280 construct<RealLiteralConstant::Real>()), 281 maybe(underscore >> kindParam))) 282 283 // R718 complex-literal-constant -> ( real-part , imag-part ) 284 TYPE_CONTEXT_PARSER("COMPLEX literal constant"_en_US, 285 parenthesized(construct<ComplexLiteralConstant>( 286 Parser<ComplexPart>{} / ",", Parser<ComplexPart>{}))) 287 288 // PGI/Intel extension: signed complex literal constant 289 TYPE_PARSER(construct<SignedComplexLiteralConstant>( 290 sign, Parser<ComplexLiteralConstant>{})) 291 292 // R719 real-part -> 293 // signed-int-literal-constant | signed-real-literal-constant | 294 // named-constant 295 // R720 imag-part -> 296 // signed-int-literal-constant | signed-real-literal-constant | 297 // named-constant 298 TYPE_PARSER(construct<ComplexPart>(signedRealLiteralConstant) || 299 construct<ComplexPart>(signedIntLiteralConstant) || 300 construct<ComplexPart>(namedConstant)) 301 302 // R721 char-selector -> 303 // length-selector | 304 // ( LEN = type-param-value , KIND = scalar-int-constant-expr ) | 305 // ( type-param-value , [KIND =] scalar-int-constant-expr ) | 306 // ( KIND = scalar-int-constant-expr [, LEN = type-param-value] ) 307 TYPE_PARSER(construct<CharSelector>(Parser<LengthSelector>{}) || 308 parenthesized(construct<CharSelector>( 309 "LEN =" >> typeParamValue, ", KIND =" >> scalarIntConstantExpr)) || 310 parenthesized(construct<CharSelector>( 311 typeParamValue / ",", maybe("KIND ="_tok) >> scalarIntConstantExpr)) || 312 parenthesized(construct<CharSelector>( 313 "KIND =" >> scalarIntConstantExpr, maybe(", LEN =" >> typeParamValue)))) 314 315 // R722 length-selector -> ( [LEN =] type-param-value ) | * char-length [,] 316 // N.B. The trailing [,] in the production is permitted by the Standard 317 // only in the context of a type-declaration-stmt, but even with that 318 // limitation, it would seem to be unnecessary and buggy to consume the comma 319 // here. 320 TYPE_PARSER(construct<LengthSelector>( 321 parenthesized(maybe("LEN ="_tok) >> typeParamValue)) || 322 construct<LengthSelector>("*" >> charLength /* / maybe(","_tok) */)) 323 324 // R723 char-length -> ( type-param-value ) | digit-string 325 TYPE_PARSER(construct<CharLength>(parenthesized(typeParamValue)) || 326 construct<CharLength>(space >> digitString64 / spaceCheck)) 327 328 // R724 char-literal-constant -> 329 // [kind-param _] ' [rep-char]... ' | 330 // [kind-param _] " [rep-char]... " 331 // "rep-char" is any non-control character. Doubled interior quotes are 332 // combined. Backslash escapes can be enabled. 333 // N.B. the parsing of "kind-param" takes care to not consume the '_'. 334 TYPE_CONTEXT_PARSER("CHARACTER literal constant"_en_US, 335 construct<CharLiteralConstant>( 336 kindParam / underscore, charLiteralConstantWithoutKind) || 337 construct<CharLiteralConstant>(construct<std::optional<KindParam>>(), 338 space >> charLiteralConstantWithoutKind)) 339 340 TYPE_CONTEXT_PARSER( 341 "Hollerith"_en_US, construct<HollerithLiteralConstant>(rawHollerithLiteral)) 342 343 // R725 logical-literal-constant -> 344 // .TRUE. [_ kind-param] | .FALSE. [_ kind-param] 345 // Also accept .T. and .F. as extensions. 346 TYPE_PARSER(construct<LogicalLiteralConstant>( 347 logicalTRUE, maybe(underscore >> kindParam)) || 348 construct<LogicalLiteralConstant>( 349 logicalFALSE, maybe(underscore >> kindParam))) 350 351 // R726 derived-type-def -> 352 // derived-type-stmt [type-param-def-stmt]... 353 // [private-or-sequence]... [component-part] 354 // [type-bound-procedure-part] end-type-stmt 355 // R735 component-part -> [component-def-stmt]... 356 TYPE_CONTEXT_PARSER("derived type definition"_en_US, 357 construct<DerivedTypeDef>(statement(Parser<DerivedTypeStmt>{}), 358 many(unambiguousStatement(Parser<TypeParamDefStmt>{})), 359 many(statement(Parser<PrivateOrSequence>{})), 360 many(inContext("component"_en_US, 361 unambiguousStatement(Parser<ComponentDefStmt>{}))), 362 maybe(Parser<TypeBoundProcedurePart>{}), 363 statement(Parser<EndTypeStmt>{}))) 364 365 // R727 derived-type-stmt -> 366 // TYPE [[, type-attr-spec-list] ::] type-name [( 367 // type-param-name-list )] 368 TYPE_CONTEXT_PARSER("TYPE statement"_en_US, 369 construct<DerivedTypeStmt>( 370 "TYPE" >> optionalListBeforeColons(Parser<TypeAttrSpec>{}), name, 371 defaulted(parenthesized(nonemptyList(name))))) 372 373 // R728 type-attr-spec -> 374 // ABSTRACT | access-spec | BIND(C) | EXTENDS ( parent-type-name ) 375 TYPE_PARSER(construct<TypeAttrSpec>(construct<Abstract>("ABSTRACT"_tok)) || 376 construct<TypeAttrSpec>(construct<TypeAttrSpec::BindC>("BIND ( C )"_tok)) || 377 construct<TypeAttrSpec>( 378 construct<TypeAttrSpec::Extends>("EXTENDS" >> parenthesized(name))) || 379 construct<TypeAttrSpec>(accessSpec)) 380 381 // R729 private-or-sequence -> private-components-stmt | sequence-stmt 382 TYPE_PARSER(construct<PrivateOrSequence>(Parser<PrivateStmt>{}) || 383 construct<PrivateOrSequence>(Parser<SequenceStmt>{})) 384 385 // R730 end-type-stmt -> END TYPE [type-name] 386 TYPE_PARSER(construct<EndTypeStmt>( 387 recovery("END TYPE" >> maybe(name), endStmtErrorRecovery))) 388 389 // R731 sequence-stmt -> SEQUENCE 390 TYPE_PARSER(construct<SequenceStmt>("SEQUENCE"_tok)) 391 392 // R732 type-param-def-stmt -> 393 // integer-type-spec , type-param-attr-spec :: type-param-decl-list 394 // R734 type-param-attr-spec -> KIND | LEN 395 constexpr auto kindOrLen{"KIND" >> pure(common::TypeParamAttr::Kind) || 396 "LEN" >> pure(common::TypeParamAttr::Len)}; 397 TYPE_PARSER(construct<TypeParamDefStmt>(integerTypeSpec / ",", kindOrLen, 398 "::" >> nonemptyList("expected type parameter declarations"_err_en_US, 399 Parser<TypeParamDecl>{}))) 400 401 // R733 type-param-decl -> type-param-name [= scalar-int-constant-expr] 402 TYPE_PARSER(construct<TypeParamDecl>(name, maybe("=" >> scalarIntConstantExpr))) 403 404 // R736 component-def-stmt -> data-component-def-stmt | 405 // proc-component-def-stmt 406 // Accidental extension not enabled here: PGI accepts type-param-def-stmt in 407 // component-part of derived-type-def. 408 TYPE_PARSER(recovery( 409 withMessage("expected component definition"_err_en_US, 410 first(construct<ComponentDefStmt>(Parser<DataComponentDefStmt>{}), 411 construct<ComponentDefStmt>(Parser<ProcComponentDefStmt>{}))), 412 construct<ComponentDefStmt>(inStmtErrorRecovery))) 413 414 // R737 data-component-def-stmt -> 415 // declaration-type-spec [[, component-attr-spec-list] ::] 416 // component-decl-list 417 // N.B. The standard requires double colons if there's an initializer. 418 TYPE_PARSER(construct<DataComponentDefStmt>(declarationTypeSpec, 419 optionalListBeforeColons(Parser<ComponentAttrSpec>{}), 420 nonemptyList("expected component declarations"_err_en_US, 421 Parser<ComponentOrFill>{}))) 422 423 // R738 component-attr-spec -> 424 // access-spec | ALLOCATABLE | 425 // CODIMENSION lbracket coarray-spec rbracket | 426 // CONTIGUOUS | DIMENSION ( component-array-spec ) | POINTER 427 TYPE_PARSER(construct<ComponentAttrSpec>(accessSpec) || 428 construct<ComponentAttrSpec>(allocatable) || 429 construct<ComponentAttrSpec>("CODIMENSION" >> coarraySpec) || 430 construct<ComponentAttrSpec>(contiguous) || 431 construct<ComponentAttrSpec>("DIMENSION" >> Parser<ComponentArraySpec>{}) || 432 construct<ComponentAttrSpec>(pointer) || 433 construct<ComponentAttrSpec>(recovery( 434 fail<ErrorRecovery>( 435 "type parameter definitions must appear before component declarations"_err_en_US), 436 kindOrLen >> construct<ErrorRecovery>()))) 437 438 // R739 component-decl -> 439 // component-name [( component-array-spec )] 440 // [lbracket coarray-spec rbracket] [* char-length] 441 // [component-initialization] 442 TYPE_CONTEXT_PARSER("component declaration"_en_US, 443 construct<ComponentDecl>(name, maybe(Parser<ComponentArraySpec>{}), 444 maybe(coarraySpec), maybe("*" >> charLength), maybe(initialization))) 445 // The source field of the Name will be replaced with a distinct generated name. 446 TYPE_CONTEXT_PARSER("%FILL item"_en_US, 447 extension<LanguageFeature::DECStructures>( 448 "nonstandard usage: %FILL"_port_en_US, 449 construct<FillDecl>(space >> sourced("%FILL" >> construct<Name>()), 450 maybe(Parser<ComponentArraySpec>{}), maybe("*" >> charLength)))) 451 TYPE_PARSER(construct<ComponentOrFill>(Parser<ComponentDecl>{}) || 452 construct<ComponentOrFill>(Parser<FillDecl>{})) 453 454 // R740 component-array-spec -> 455 // explicit-shape-spec-list | deferred-shape-spec-list 456 // N.B. Parenthesized here rather than around references to this production. 457 TYPE_PARSER(construct<ComponentArraySpec>(parenthesized( 458 nonemptyList("expected explicit shape specifications"_err_en_US, 459 explicitShapeSpec))) || 460 construct<ComponentArraySpec>(parenthesized(deferredShapeSpecList))) 461 462 // R741 proc-component-def-stmt -> 463 // PROCEDURE ( [proc-interface] ) , proc-component-attr-spec-list 464 // :: proc-decl-list 465 TYPE_CONTEXT_PARSER("PROCEDURE component definition statement"_en_US, 466 construct<ProcComponentDefStmt>( 467 "PROCEDURE" >> parenthesized(maybe(procInterface)), 468 localRecovery("expected PROCEDURE component attributes"_err_en_US, 469 "," >> nonemptyList(Parser<ProcComponentAttrSpec>{}), ok), 470 localRecovery("expected PROCEDURE declarations"_err_en_US, 471 "::" >> nonemptyList(procDecl), SkipTo<'\n'>{}))) 472 473 // R742 proc-component-attr-spec -> 474 // access-spec | NOPASS | PASS [(arg-name)] | POINTER 475 constexpr auto noPass{construct<NoPass>("NOPASS"_tok)}; 476 constexpr auto pass{construct<Pass>("PASS" >> maybe(parenthesized(name)))}; 477 TYPE_PARSER(construct<ProcComponentAttrSpec>(accessSpec) || 478 construct<ProcComponentAttrSpec>(noPass) || 479 construct<ProcComponentAttrSpec>(pass) || 480 construct<ProcComponentAttrSpec>(pointer)) 481 482 // R744 initial-data-target -> designator 483 constexpr auto initialDataTarget{indirect(designator)}; 484 485 // R743 component-initialization -> 486 // = constant-expr | => null-init | => initial-data-target 487 // R805 initialization -> 488 // = constant-expr | => null-init | => initial-data-target 489 // Universal extension: initialization -> / data-stmt-value-list / 490 TYPE_PARSER(construct<Initialization>("=>" >> nullInit) || 491 construct<Initialization>("=>" >> initialDataTarget) || 492 construct<Initialization>("=" >> constantExpr) || 493 extension<LanguageFeature::SlashInitialization>( 494 "nonstandard usage: /initialization/"_port_en_US, 495 construct<Initialization>( 496 "/" >> nonemptyList("expected values"_err_en_US, 497 indirect(Parser<DataStmtValue>{})) / 498 "/"))) 499 500 // R745 private-components-stmt -> PRIVATE 501 // R747 binding-private-stmt -> PRIVATE 502 TYPE_PARSER(construct<PrivateStmt>("PRIVATE"_tok)) 503 504 // R746 type-bound-procedure-part -> 505 // contains-stmt [binding-private-stmt] [type-bound-proc-binding]... 506 TYPE_CONTEXT_PARSER("type bound procedure part"_en_US, 507 construct<TypeBoundProcedurePart>(statement(containsStmt), 508 maybe(statement(Parser<PrivateStmt>{})), 509 many(statement(Parser<TypeBoundProcBinding>{})))) 510 511 // R748 type-bound-proc-binding -> 512 // type-bound-procedure-stmt | type-bound-generic-stmt | 513 // final-procedure-stmt 514 TYPE_CONTEXT_PARSER("type bound procedure binding"_en_US, 515 recovery( 516 first(construct<TypeBoundProcBinding>(Parser<TypeBoundProcedureStmt>{}), 517 construct<TypeBoundProcBinding>(Parser<TypeBoundGenericStmt>{}), 518 construct<TypeBoundProcBinding>(Parser<FinalProcedureStmt>{})), 519 construct<TypeBoundProcBinding>( 520 !"END"_tok >> SkipTo<'\n'>{} >> construct<ErrorRecovery>()))) 521 522 // R749 type-bound-procedure-stmt -> 523 // PROCEDURE [[, bind-attr-list] ::] type-bound-proc-decl-list | 524 // PROCEDURE ( interface-name ) , bind-attr-list :: binding-name-list 525 TYPE_CONTEXT_PARSER("type bound PROCEDURE statement"_en_US, 526 "PROCEDURE" >> 527 (construct<TypeBoundProcedureStmt>( 528 construct<TypeBoundProcedureStmt::WithInterface>( 529 parenthesized(name), 530 localRecovery("expected list of binding attributes"_err_en_US, 531 "," >> nonemptyList(Parser<BindAttr>{}), ok), 532 localRecovery("expected list of binding names"_err_en_US, 533 "::" >> listOfNames, SkipTo<'\n'>{}))) || 534 construct<TypeBoundProcedureStmt>( 535 construct<TypeBoundProcedureStmt::WithoutInterface>( 536 optionalListBeforeColons(Parser<BindAttr>{}), 537 nonemptyList( 538 "expected type bound procedure declarations"_err_en_US, 539 Parser<TypeBoundProcDecl>{}))))) 540 541 // R750 type-bound-proc-decl -> binding-name [=> procedure-name] 542 TYPE_PARSER(construct<TypeBoundProcDecl>(name, maybe("=>" >> name))) 543 544 // R751 type-bound-generic-stmt -> 545 // GENERIC [, access-spec] :: generic-spec => binding-name-list 546 TYPE_CONTEXT_PARSER("type bound GENERIC statement"_en_US, 547 construct<TypeBoundGenericStmt>("GENERIC" >> maybe("," >> accessSpec), 548 "::" >> indirect(genericSpec), "=>" >> listOfNames)) 549 550 // R752 bind-attr -> 551 // access-spec | DEFERRED | NON_OVERRIDABLE | NOPASS | PASS [(arg-name)] 552 TYPE_PARSER(construct<BindAttr>(accessSpec) || 553 construct<BindAttr>(construct<BindAttr::Deferred>("DEFERRED"_tok)) || 554 construct<BindAttr>( 555 construct<BindAttr::Non_Overridable>("NON_OVERRIDABLE"_tok)) || 556 construct<BindAttr>(noPass) || construct<BindAttr>(pass)) 557 558 // R753 final-procedure-stmt -> FINAL [::] final-subroutine-name-list 559 TYPE_CONTEXT_PARSER("FINAL statement"_en_US, 560 construct<FinalProcedureStmt>("FINAL" >> maybe("::"_tok) >> listOfNames)) 561 562 // R754 derived-type-spec -> type-name [(type-param-spec-list)] 563 TYPE_PARSER(construct<DerivedTypeSpec>(name, 564 defaulted(parenthesized(nonemptyList( 565 "expected type parameters"_err_en_US, Parser<TypeParamSpec>{}))))) 566 567 // R755 type-param-spec -> [keyword =] type-param-value 568 TYPE_PARSER(construct<TypeParamSpec>(maybe(keyword / "="), typeParamValue)) 569 570 // R756 structure-constructor -> derived-type-spec ( [component-spec-list] ) 571 TYPE_PARSER((construct<StructureConstructor>(derivedTypeSpec, 572 parenthesized(optionalList(Parser<ComponentSpec>{}))) || 573 // This alternative corrects misrecognition of the 574 // component-spec-list as the type-param-spec-list in 575 // derived-type-spec. 576 construct<StructureConstructor>( 577 construct<DerivedTypeSpec>( 578 name, construct<std::list<TypeParamSpec>>()), 579 parenthesized(optionalList(Parser<ComponentSpec>{})))) / 580 !"("_tok) 581 582 // R757 component-spec -> [keyword =] component-data-source 583 TYPE_PARSER(construct<ComponentSpec>( 584 maybe(keyword / "="), Parser<ComponentDataSource>{})) 585 586 // R758 component-data-source -> expr | data-target | proc-target 587 TYPE_PARSER(construct<ComponentDataSource>(indirect(expr))) 588 589 // R759 enum-def -> 590 // enum-def-stmt enumerator-def-stmt [enumerator-def-stmt]... 591 // end-enum-stmt 592 TYPE_CONTEXT_PARSER("enum definition"_en_US, 593 construct<EnumDef>(statement(Parser<EnumDefStmt>{}), 594 some(unambiguousStatement(Parser<EnumeratorDefStmt>{})), 595 statement(Parser<EndEnumStmt>{}))) 596 597 // R760 enum-def-stmt -> ENUM, BIND(C) 598 TYPE_PARSER(construct<EnumDefStmt>("ENUM , BIND ( C )"_tok)) 599 600 // R761 enumerator-def-stmt -> ENUMERATOR [::] enumerator-list 601 TYPE_CONTEXT_PARSER("ENUMERATOR statement"_en_US, 602 construct<EnumeratorDefStmt>("ENUMERATOR" >> maybe("::"_tok) >> 603 nonemptyList("expected enumerators"_err_en_US, Parser<Enumerator>{}))) 604 605 // R762 enumerator -> named-constant [= scalar-int-constant-expr] 606 TYPE_PARSER( 607 construct<Enumerator>(namedConstant, maybe("=" >> scalarIntConstantExpr))) 608 609 // R763 end-enum-stmt -> END ENUM 610 TYPE_PARSER(recovery("END ENUM"_tok, "END" >> SkipPast<'\n'>{}) >> 611 construct<EndEnumStmt>()) 612 613 // R801 type-declaration-stmt -> 614 // declaration-type-spec [[, attr-spec]... ::] entity-decl-list 615 constexpr auto entityDeclWithoutEqInit{construct<EntityDecl>(name, 616 maybe(arraySpec), maybe(coarraySpec), maybe("*" >> charLength), 617 !"="_tok >> maybe(initialization))}; // old-style REAL A/0/ still works 618 TYPE_PARSER( 619 construct<TypeDeclarationStmt>(declarationTypeSpec, 620 defaulted("," >> nonemptyList(Parser<AttrSpec>{})) / "::", 621 nonemptyList("expected entity declarations"_err_en_US, entityDecl)) || 622 // C806: no initializers allowed without colons ("REALA=1" is ambiguous) 623 construct<TypeDeclarationStmt>(declarationTypeSpec, 624 construct<std::list<AttrSpec>>(), 625 nonemptyList("expected entity declarations"_err_en_US, 626 entityDeclWithoutEqInit)) || 627 // PGI-only extension: comma in place of doubled colons 628 extension<LanguageFeature::MissingColons>( 629 "nonstandard usage: ',' in place of '::'"_port_en_US, 630 construct<TypeDeclarationStmt>(declarationTypeSpec, 631 defaulted("," >> nonemptyList(Parser<AttrSpec>{})), 632 withMessage("expected entity declarations"_err_en_US, 633 "," >> nonemptyList(entityDecl))))) 634 635 // R802 attr-spec -> 636 // access-spec | ALLOCATABLE | ASYNCHRONOUS | 637 // CODIMENSION lbracket coarray-spec rbracket | CONTIGUOUS | 638 // DIMENSION ( array-spec ) | EXTERNAL | INTENT ( intent-spec ) | 639 // INTRINSIC | language-binding-spec | OPTIONAL | PARAMETER | POINTER | 640 // PROTECTED | SAVE | TARGET | VALUE | VOLATILE 641 TYPE_PARSER(construct<AttrSpec>(accessSpec) || 642 construct<AttrSpec>(allocatable) || 643 construct<AttrSpec>(construct<Asynchronous>("ASYNCHRONOUS"_tok)) || 644 construct<AttrSpec>("CODIMENSION" >> coarraySpec) || 645 construct<AttrSpec>(contiguous) || 646 construct<AttrSpec>("DIMENSION" >> arraySpec) || 647 construct<AttrSpec>(construct<External>("EXTERNAL"_tok)) || 648 construct<AttrSpec>("INTENT" >> parenthesized(intentSpec)) || 649 construct<AttrSpec>(construct<Intrinsic>("INTRINSIC"_tok)) || 650 construct<AttrSpec>(languageBindingSpec) || construct<AttrSpec>(optional) || 651 construct<AttrSpec>(construct<Parameter>("PARAMETER"_tok)) || 652 construct<AttrSpec>(pointer) || construct<AttrSpec>(protectedAttr) || 653 construct<AttrSpec>(save) || 654 construct<AttrSpec>(construct<Target>("TARGET"_tok)) || 655 construct<AttrSpec>(construct<Value>("VALUE"_tok)) || 656 construct<AttrSpec>(construct<Volatile>("VOLATILE"_tok))) 657 658 // R804 object-name -> name 659 constexpr auto objectName{name}; 660 661 // R803 entity-decl -> 662 // object-name [( array-spec )] [lbracket coarray-spec rbracket] 663 // [* char-length] [initialization] | 664 // function-name [* char-length] 665 TYPE_PARSER(construct<EntityDecl>(objectName, maybe(arraySpec), 666 maybe(coarraySpec), maybe("*" >> charLength), maybe(initialization))) 667 668 // R806 null-init -> function-reference ... which must resolve to NULL() 669 TYPE_PARSER(lookAhead(name / "( )") >> construct<NullInit>(expr)) 670 671 // R807 access-spec -> PUBLIC | PRIVATE 672 TYPE_PARSER(construct<AccessSpec>("PUBLIC" >> pure(AccessSpec::Kind::Public)) || 673 construct<AccessSpec>("PRIVATE" >> pure(AccessSpec::Kind::Private))) 674 675 // R808 language-binding-spec -> 676 // BIND ( C [, NAME = scalar-default-char-constant-expr] ) 677 // R1528 proc-language-binding-spec -> language-binding-spec 678 TYPE_PARSER(construct<LanguageBindingSpec>( 679 "BIND ( C" >> maybe(", NAME =" >> scalarDefaultCharConstantExpr) / ")")) 680 681 // R809 coarray-spec -> deferred-coshape-spec-list | explicit-coshape-spec 682 // N.B. Bracketed here rather than around references, for consistency with 683 // array-spec. 684 TYPE_PARSER( 685 construct<CoarraySpec>(bracketed(Parser<DeferredCoshapeSpecList>{})) || 686 construct<CoarraySpec>(bracketed(Parser<ExplicitCoshapeSpec>{}))) 687 688 // R810 deferred-coshape-spec -> : 689 // deferred-coshape-spec-list - just a list of colons 690 inline int listLength(std::list<Success> &&xs) { return xs.size(); } 691 692 TYPE_PARSER(construct<DeferredCoshapeSpecList>( 693 applyFunction(listLength, nonemptyList(":"_tok)))) 694 695 // R811 explicit-coshape-spec -> 696 // [[lower-cobound :] upper-cobound ,]... [lower-cobound :] * 697 // R812 lower-cobound -> specification-expr 698 // R813 upper-cobound -> specification-expr 699 TYPE_PARSER(construct<ExplicitCoshapeSpec>( 700 many(explicitShapeSpec / ","), maybe(specificationExpr / ":") / "*")) 701 702 // R815 array-spec -> 703 // explicit-shape-spec-list | assumed-shape-spec-list | 704 // deferred-shape-spec-list | assumed-size-spec | implied-shape-spec | 705 // implied-shape-or-assumed-size-spec | assumed-rank-spec 706 // N.B. Parenthesized here rather than around references to avoid 707 // a need for forced look-ahead. 708 // Shape specs that could be deferred-shape-spec or assumed-shape-spec 709 // (e.g. '(:,:)') are parsed as the former. 710 TYPE_PARSER( 711 construct<ArraySpec>(parenthesized(nonemptyList(explicitShapeSpec))) || 712 construct<ArraySpec>(parenthesized(deferredShapeSpecList)) || 713 construct<ArraySpec>( 714 parenthesized(nonemptyList(Parser<AssumedShapeSpec>{}))) || 715 construct<ArraySpec>(parenthesized(Parser<AssumedSizeSpec>{})) || 716 construct<ArraySpec>(parenthesized(Parser<ImpliedShapeSpec>{})) || 717 construct<ArraySpec>(parenthesized(Parser<AssumedRankSpec>{}))) 718 719 // R816 explicit-shape-spec -> [lower-bound :] upper-bound 720 // R817 lower-bound -> specification-expr 721 // R818 upper-bound -> specification-expr 722 TYPE_PARSER(construct<ExplicitShapeSpec>( 723 maybe(specificationExpr / ":"), specificationExpr)) 724 725 // R819 assumed-shape-spec -> [lower-bound] : 726 TYPE_PARSER(construct<AssumedShapeSpec>(maybe(specificationExpr) / ":")) 727 728 // R820 deferred-shape-spec -> : 729 // deferred-shape-spec-list - just a list of colons 730 TYPE_PARSER(construct<DeferredShapeSpecList>( 731 applyFunction(listLength, nonemptyList(":"_tok)))) 732 733 // R821 assumed-implied-spec -> [lower-bound :] * 734 TYPE_PARSER(construct<AssumedImpliedSpec>(maybe(specificationExpr / ":") / "*")) 735 736 // R822 assumed-size-spec -> explicit-shape-spec-list , assumed-implied-spec 737 TYPE_PARSER(construct<AssumedSizeSpec>( 738 nonemptyList(explicitShapeSpec) / ",", assumedImpliedSpec)) 739 740 // R823 implied-shape-or-assumed-size-spec -> assumed-implied-spec 741 // R824 implied-shape-spec -> assumed-implied-spec , assumed-implied-spec-list 742 // I.e., when the assumed-implied-spec-list has a single item, it constitutes an 743 // implied-shape-or-assumed-size-spec; otherwise, an implied-shape-spec. 744 TYPE_PARSER(construct<ImpliedShapeSpec>(nonemptyList(assumedImpliedSpec))) 745 746 // R825 assumed-rank-spec -> .. 747 TYPE_PARSER(construct<AssumedRankSpec>(".."_tok)) 748 749 // R826 intent-spec -> IN | OUT | INOUT 750 TYPE_PARSER(construct<IntentSpec>("IN OUT" >> pure(IntentSpec::Intent::InOut) || 751 "IN" >> pure(IntentSpec::Intent::In) || 752 "OUT" >> pure(IntentSpec::Intent::Out))) 753 754 // R827 access-stmt -> access-spec [[::] access-id-list] 755 TYPE_PARSER(construct<AccessStmt>(accessSpec, 756 defaulted(maybe("::"_tok) >> 757 nonemptyList("expected names and generic specifications"_err_en_US, 758 Parser<AccessId>{})))) 759 760 // R828 access-id -> access-name | generic-spec 761 TYPE_PARSER(construct<AccessId>(indirect(genericSpec)) || 762 construct<AccessId>(name)) // initially ambiguous with genericSpec 763 764 // R829 allocatable-stmt -> ALLOCATABLE [::] allocatable-decl-list 765 TYPE_PARSER(construct<AllocatableStmt>("ALLOCATABLE" >> maybe("::"_tok) >> 766 nonemptyList( 767 "expected object declarations"_err_en_US, Parser<ObjectDecl>{}))) 768 769 // R830 allocatable-decl -> 770 // object-name [( array-spec )] [lbracket coarray-spec rbracket] 771 // R860 target-decl -> 772 // object-name [( array-spec )] [lbracket coarray-spec rbracket] 773 TYPE_PARSER( 774 construct<ObjectDecl>(objectName, maybe(arraySpec), maybe(coarraySpec))) 775 776 // R831 asynchronous-stmt -> ASYNCHRONOUS [::] object-name-list 777 TYPE_PARSER(construct<AsynchronousStmt>("ASYNCHRONOUS" >> maybe("::"_tok) >> 778 nonemptyList("expected object names"_err_en_US, objectName))) 779 780 // R832 bind-stmt -> language-binding-spec [::] bind-entity-list 781 TYPE_PARSER(construct<BindStmt>(languageBindingSpec / maybe("::"_tok), 782 nonemptyList("expected bind entities"_err_en_US, Parser<BindEntity>{}))) 783 784 // R833 bind-entity -> entity-name | / common-block-name / 785 TYPE_PARSER(construct<BindEntity>(pure(BindEntity::Kind::Object), name) || 786 construct<BindEntity>("/" >> pure(BindEntity::Kind::Common), name / "/")) 787 788 // R834 codimension-stmt -> CODIMENSION [::] codimension-decl-list 789 TYPE_PARSER(construct<CodimensionStmt>("CODIMENSION" >> maybe("::"_tok) >> 790 nonemptyList("expected codimension declarations"_err_en_US, 791 Parser<CodimensionDecl>{}))) 792 793 // R835 codimension-decl -> coarray-name lbracket coarray-spec rbracket 794 TYPE_PARSER(construct<CodimensionDecl>(name, coarraySpec)) 795 796 // R836 contiguous-stmt -> CONTIGUOUS [::] object-name-list 797 TYPE_PARSER(construct<ContiguousStmt>("CONTIGUOUS" >> maybe("::"_tok) >> 798 nonemptyList("expected object names"_err_en_US, objectName))) 799 800 // R837 data-stmt -> DATA data-stmt-set [[,] data-stmt-set]... 801 TYPE_CONTEXT_PARSER("DATA statement"_en_US, 802 construct<DataStmt>( 803 "DATA" >> nonemptySeparated(Parser<DataStmtSet>{}, maybe(","_tok)))) 804 805 // R838 data-stmt-set -> data-stmt-object-list / data-stmt-value-list / 806 TYPE_PARSER(construct<DataStmtSet>( 807 nonemptyList( 808 "expected DATA statement objects"_err_en_US, Parser<DataStmtObject>{}), 809 withMessage("expected DATA statement value list"_err_en_US, 810 "/"_tok >> nonemptyList("expected DATA statement values"_err_en_US, 811 Parser<DataStmtValue>{})) / 812 "/")) 813 814 // R839 data-stmt-object -> variable | data-implied-do 815 TYPE_PARSER(construct<DataStmtObject>(indirect(variable)) || 816 construct<DataStmtObject>(dataImpliedDo)) 817 818 // R840 data-implied-do -> 819 // ( data-i-do-object-list , [integer-type-spec ::] data-i-do-variable 820 // = scalar-int-constant-expr , scalar-int-constant-expr 821 // [, scalar-int-constant-expr] ) 822 // R842 data-i-do-variable -> do-variable 823 TYPE_PARSER(parenthesized(construct<DataImpliedDo>( 824 nonemptyList(Parser<DataIDoObject>{} / lookAhead(","_tok)) / ",", 825 maybe(integerTypeSpec / "::"), loopBounds(scalarIntConstantExpr)))) 826 827 // R841 data-i-do-object -> 828 // array-element | scalar-structure-component | data-implied-do 829 TYPE_PARSER(construct<DataIDoObject>(scalar(indirect(designator))) || 830 construct<DataIDoObject>(indirect(dataImpliedDo))) 831 832 // R843 data-stmt-value -> [data-stmt-repeat *] data-stmt-constant 833 TYPE_PARSER(construct<DataStmtValue>( 834 maybe(Parser<DataStmtRepeat>{} / "*"), Parser<DataStmtConstant>{})) 835 836 // R847 constant-subobject -> designator 837 // R846 int-constant-subobject -> constant-subobject 838 constexpr auto constantSubobject{constant(indirect(designator))}; 839 840 // R844 data-stmt-repeat -> scalar-int-constant | scalar-int-constant-subobject 841 // R607 int-constant -> constant 842 // Factored into: constant -> literal-constant -> int-literal-constant 843 // The named-constant alternative of constant is subsumed by constant-subobject 844 TYPE_PARSER(construct<DataStmtRepeat>(intLiteralConstant) || 845 construct<DataStmtRepeat>(scalar(integer(constantSubobject)))) 846 847 // R845 data-stmt-constant -> 848 // scalar-constant | scalar-constant-subobject | 849 // signed-int-literal-constant | signed-real-literal-constant | 850 // null-init | initial-data-target | 851 // constant-structure-constructor 852 // N.B. scalar-constant and scalar-constant-subobject are ambiguous with 853 // initial-data-target; null-init and structure-constructor are ambiguous 854 // in the absence of parameters and components; structure-constructor with 855 // components can be ambiguous with a scalar-constant-subobject. 856 // So we parse literal constants, designator, null-init, and 857 // structure-constructor, so that semantics can figure things out later 858 // with the symbol table. 859 TYPE_PARSER(sourced(first(construct<DataStmtConstant>(literalConstant), 860 construct<DataStmtConstant>(signedRealLiteralConstant), 861 construct<DataStmtConstant>(signedIntLiteralConstant), 862 extension<LanguageFeature::SignedComplexLiteral>( 863 "nonstandard usage: signed COMPLEX literal"_port_en_US, 864 construct<DataStmtConstant>(Parser<SignedComplexLiteralConstant>{})), 865 construct<DataStmtConstant>(nullInit), 866 construct<DataStmtConstant>(indirect(designator) / !"("_tok), 867 construct<DataStmtConstant>(Parser<StructureConstructor>{})))) 868 869 // R848 dimension-stmt -> 870 // DIMENSION [::] array-name ( array-spec ) 871 // [, array-name ( array-spec )]... 872 TYPE_CONTEXT_PARSER("DIMENSION statement"_en_US, 873 construct<DimensionStmt>("DIMENSION" >> maybe("::"_tok) >> 874 nonemptyList("expected array specifications"_err_en_US, 875 construct<DimensionStmt::Declaration>(name, arraySpec)))) 876 877 // R849 intent-stmt -> INTENT ( intent-spec ) [::] dummy-arg-name-list 878 TYPE_CONTEXT_PARSER("INTENT statement"_en_US, 879 construct<IntentStmt>( 880 "INTENT" >> parenthesized(intentSpec) / maybe("::"_tok), listOfNames)) 881 882 // R850 optional-stmt -> OPTIONAL [::] dummy-arg-name-list 883 TYPE_PARSER( 884 construct<OptionalStmt>("OPTIONAL" >> maybe("::"_tok) >> listOfNames)) 885 886 // R851 parameter-stmt -> PARAMETER ( named-constant-def-list ) 887 // Legacy extension: omitted parentheses, no implicit typing from names 888 TYPE_CONTEXT_PARSER("PARAMETER statement"_en_US, 889 construct<ParameterStmt>( 890 "PARAMETER" >> parenthesized(nonemptyList(Parser<NamedConstantDef>{})))) 891 TYPE_CONTEXT_PARSER("old style PARAMETER statement"_en_US, 892 extension<LanguageFeature::OldStyleParameter>( 893 "nonstandard usage: PARAMETER without parentheses"_port_en_US, 894 construct<OldParameterStmt>( 895 "PARAMETER" >> nonemptyList(Parser<NamedConstantDef>{})))) 896 897 // R852 named-constant-def -> named-constant = constant-expr 898 TYPE_PARSER(construct<NamedConstantDef>(namedConstant, "=" >> constantExpr)) 899 900 // R853 pointer-stmt -> POINTER [::] pointer-decl-list 901 TYPE_PARSER(construct<PointerStmt>("POINTER" >> maybe("::"_tok) >> 902 nonemptyList( 903 "expected pointer declarations"_err_en_US, Parser<PointerDecl>{}))) 904 905 // R854 pointer-decl -> 906 // object-name [( deferred-shape-spec-list )] | proc-entity-name 907 TYPE_PARSER( 908 construct<PointerDecl>(name, maybe(parenthesized(deferredShapeSpecList)))) 909 910 // R855 protected-stmt -> PROTECTED [::] entity-name-list 911 TYPE_PARSER( 912 construct<ProtectedStmt>("PROTECTED" >> maybe("::"_tok) >> listOfNames)) 913 914 // R856 save-stmt -> SAVE [[::] saved-entity-list] 915 TYPE_PARSER(construct<SaveStmt>( 916 "SAVE" >> defaulted(maybe("::"_tok) >> 917 nonemptyList("expected SAVE entities"_err_en_US, 918 Parser<SavedEntity>{})))) 919 920 // R857 saved-entity -> object-name | proc-pointer-name | / common-block-name / 921 // R858 proc-pointer-name -> name 922 TYPE_PARSER(construct<SavedEntity>(pure(SavedEntity::Kind::Entity), name) || 923 construct<SavedEntity>("/" >> pure(SavedEntity::Kind::Common), name / "/")) 924 925 // R859 target-stmt -> TARGET [::] target-decl-list 926 TYPE_PARSER(construct<TargetStmt>("TARGET" >> maybe("::"_tok) >> 927 nonemptyList("expected objects"_err_en_US, Parser<ObjectDecl>{}))) 928 929 // R861 value-stmt -> VALUE [::] dummy-arg-name-list 930 TYPE_PARSER(construct<ValueStmt>("VALUE" >> maybe("::"_tok) >> listOfNames)) 931 932 // R862 volatile-stmt -> VOLATILE [::] object-name-list 933 TYPE_PARSER(construct<VolatileStmt>("VOLATILE" >> maybe("::"_tok) >> 934 nonemptyList("expected object names"_err_en_US, objectName))) 935 936 // R866 implicit-name-spec -> EXTERNAL | TYPE 937 constexpr auto implicitNameSpec{ 938 "EXTERNAL" >> pure(ImplicitStmt::ImplicitNoneNameSpec::External) || 939 "TYPE" >> pure(ImplicitStmt::ImplicitNoneNameSpec::Type)}; 940 941 // R863 implicit-stmt -> 942 // IMPLICIT implicit-spec-list | 943 // IMPLICIT NONE [( [implicit-name-spec-list] )] 944 TYPE_CONTEXT_PARSER("IMPLICIT statement"_en_US, 945 construct<ImplicitStmt>( 946 "IMPLICIT" >> nonemptyList("expected IMPLICIT specifications"_err_en_US, 947 Parser<ImplicitSpec>{})) || 948 construct<ImplicitStmt>("IMPLICIT NONE"_sptok >> 949 defaulted(parenthesized(optionalList(implicitNameSpec))))) 950 951 // R864 implicit-spec -> declaration-type-spec ( letter-spec-list ) 952 // The variant form of declarationTypeSpec is meant to avoid misrecognition 953 // of a letter-spec as a simple parenthesized expression for kind or character 954 // length, e.g., PARAMETER(I=5,N=1); IMPLICIT REAL(I-N)(O-Z) vs. 955 // IMPLICIT REAL(I-N). The variant form needs to attempt to reparse only 956 // types with optional parenthesized kind/length expressions, so derived 957 // type specs, DOUBLE PRECISION, and DOUBLE COMPLEX need not be considered. 958 constexpr auto noKindSelector{construct<std::optional<KindSelector>>()}; 959 constexpr auto implicitSpecDeclarationTypeSpecRetry{ 960 construct<DeclarationTypeSpec>(first( 961 construct<IntrinsicTypeSpec>( 962 construct<IntegerTypeSpec>("INTEGER" >> noKindSelector)), 963 construct<IntrinsicTypeSpec>( 964 construct<IntrinsicTypeSpec::Real>("REAL" >> noKindSelector)), 965 construct<IntrinsicTypeSpec>( 966 construct<IntrinsicTypeSpec::Complex>("COMPLEX" >> noKindSelector)), 967 construct<IntrinsicTypeSpec>(construct<IntrinsicTypeSpec::Character>( 968 "CHARACTER" >> construct<std::optional<CharSelector>>())), 969 construct<IntrinsicTypeSpec>(construct<IntrinsicTypeSpec::Logical>( 970 "LOGICAL" >> noKindSelector))))}; 971 972 TYPE_PARSER(construct<ImplicitSpec>(declarationTypeSpec, 973 parenthesized(nonemptyList(Parser<LetterSpec>{}))) || 974 construct<ImplicitSpec>(implicitSpecDeclarationTypeSpecRetry, 975 parenthesized(nonemptyList(Parser<LetterSpec>{})))) 976 977 // R865 letter-spec -> letter [- letter] 978 TYPE_PARSER(space >> (construct<LetterSpec>(letter, maybe("-" >> letter)) || 979 construct<LetterSpec>(otherIdChar, 980 construct<std::optional<const char *>>()))) 981 982 // R867 import-stmt -> 983 // IMPORT [[::] import-name-list] | 984 // IMPORT , ONLY : import-name-list | IMPORT , NONE | IMPORT , ALL 985 TYPE_CONTEXT_PARSER("IMPORT statement"_en_US, 986 construct<ImportStmt>( 987 "IMPORT , ONLY :" >> pure(common::ImportKind::Only), listOfNames) || 988 construct<ImportStmt>( 989 "IMPORT , NONE" >> pure(common::ImportKind::None)) || 990 construct<ImportStmt>( 991 "IMPORT , ALL" >> pure(common::ImportKind::All)) || 992 construct<ImportStmt>( 993 "IMPORT" >> maybe("::"_tok) >> optionalList(name))) 994 995 // R868 namelist-stmt -> 996 // NAMELIST / namelist-group-name / namelist-group-object-list 997 // [[,] / namelist-group-name / namelist-group-object-list]... 998 // R869 namelist-group-object -> variable-name 999 TYPE_PARSER(construct<NamelistStmt>("NAMELIST" >> 1000 nonemptySeparated( 1001 construct<NamelistStmt::Group>("/" >> name / "/", listOfNames), 1002 maybe(","_tok)))) 1003 1004 // R870 equivalence-stmt -> EQUIVALENCE equivalence-set-list 1005 // R871 equivalence-set -> ( equivalence-object , equivalence-object-list ) 1006 TYPE_PARSER(construct<EquivalenceStmt>("EQUIVALENCE" >> 1007 nonemptyList( 1008 parenthesized(nonemptyList("expected EQUIVALENCE objects"_err_en_US, 1009 Parser<EquivalenceObject>{}))))) 1010 1011 // R872 equivalence-object -> variable-name | array-element | substring 1012 TYPE_PARSER(construct<EquivalenceObject>(indirect(designator))) 1013 1014 // R873 common-stmt -> 1015 // COMMON [/ [common-block-name] /] common-block-object-list 1016 // [[,] / [common-block-name] / common-block-object-list]... 1017 TYPE_PARSER( 1018 construct<CommonStmt>("COMMON" >> defaulted("/" >> maybe(name) / "/"), 1019 nonemptyList("expected COMMON block objects"_err_en_US, 1020 Parser<CommonBlockObject>{}), 1021 many(maybe(","_tok) >> 1022 construct<CommonStmt::Block>("/" >> maybe(name) / "/", 1023 nonemptyList("expected COMMON block objects"_err_en_US, 1024 Parser<CommonBlockObject>{}))))) 1025 1026 // R874 common-block-object -> variable-name [( array-spec )] 1027 TYPE_PARSER(construct<CommonBlockObject>(name, maybe(arraySpec))) 1028 1029 // R901 designator -> object-name | array-element | array-section | 1030 // coindexed-named-object | complex-part-designator | 1031 // structure-component | substring 1032 // The Standard's productions for designator and its alternatives are 1033 // ambiguous without recourse to a symbol table. Many of the alternatives 1034 // for designator (viz., array-element, coindexed-named-object, 1035 // and structure-component) are all syntactically just data-ref. 1036 // What designator boils down to is this: 1037 // It starts with either a name or a character literal. 1038 // If it starts with a character literal, it must be a substring. 1039 // If it starts with a name, it's a sequence of %-separated parts; 1040 // each part is a name, maybe a (section-subscript-list), and 1041 // maybe an [image-selector]. 1042 // If it's a substring, it ends with (substring-range). 1043 TYPE_CONTEXT_PARSER("designator"_en_US, 1044 sourced(construct<Designator>(substring) || construct<Designator>(dataRef))) 1045 1046 constexpr auto percentOrDot{"%"_tok || 1047 // legacy VAX extension for RECORD field access 1048 extension<LanguageFeature::DECStructures>( 1049 "nonstandard usage: component access with '.' in place of '%'"_port_en_US, 1050 "."_tok / lookAhead(OldStructureComponentName{}))}; 1051 1052 // R902 variable -> designator | function-reference 1053 // This production appears to be left-recursive in the grammar via 1054 // function-reference -> procedure-designator -> proc-component-ref -> 1055 // scalar-variable 1056 // and would be so if we were to allow functions to be called via procedure 1057 // pointer components within derived type results of other function references 1058 // (a reasonable extension, esp. in the case of procedure pointer components 1059 // that are NOPASS). However, Fortran constrains the use of a variable in a 1060 // proc-component-ref to be a data-ref without coindices (C1027). 1061 // Some array element references will be misrecognized as function references. 1062 constexpr auto noMoreAddressing{!"("_tok >> !"["_tok >> !percentOrDot}; 1063 TYPE_CONTEXT_PARSER("variable"_en_US, 1064 construct<Variable>(indirect(functionReference / noMoreAddressing)) || 1065 construct<Variable>(indirect(designator))) 1066 1067 // R908 substring -> parent-string ( substring-range ) 1068 // R909 parent-string -> 1069 // scalar-variable-name | array-element | coindexed-named-object | 1070 // scalar-structure-component | scalar-char-literal-constant | 1071 // scalar-named-constant 1072 TYPE_PARSER( 1073 construct<Substring>(dataRef, parenthesized(Parser<SubstringRange>{}))) 1074 1075 TYPE_PARSER(construct<CharLiteralConstantSubstring>( 1076 charLiteralConstant, parenthesized(Parser<SubstringRange>{}))) 1077 1078 // R910 substring-range -> [scalar-int-expr] : [scalar-int-expr] 1079 TYPE_PARSER(construct<SubstringRange>( 1080 maybe(scalarIntExpr), ":" >> maybe(scalarIntExpr))) 1081 1082 // R911 data-ref -> part-ref [% part-ref]... 1083 // R914 coindexed-named-object -> data-ref 1084 // R917 array-element -> data-ref 1085 TYPE_PARSER( 1086 construct<DataRef>(nonemptySeparated(Parser<PartRef>{}, percentOrDot))) 1087 1088 // R912 part-ref -> part-name [( section-subscript-list )] [image-selector] 1089 TYPE_PARSER(construct<PartRef>(name, 1090 defaulted( 1091 parenthesized(nonemptyList(Parser<SectionSubscript>{})) / !"=>"_tok), 1092 maybe(Parser<ImageSelector>{}))) 1093 1094 // R913 structure-component -> data-ref 1095 // The final part-ref in the data-ref is not allowed to have subscripts. 1096 TYPE_PARSER(construct<StructureComponent>( 1097 construct<DataRef>(some(Parser<PartRef>{} / percentOrDot)), name)) 1098 1099 // R919 subscript -> scalar-int-expr 1100 constexpr auto subscript{scalarIntExpr}; 1101 1102 // R920 section-subscript -> subscript | subscript-triplet | vector-subscript 1103 // R923 vector-subscript -> int-expr 1104 // N.B. The distinction that needs to be made between "subscript" and 1105 // "vector-subscript" is deferred to semantic analysis. 1106 TYPE_PARSER(construct<SectionSubscript>(Parser<SubscriptTriplet>{}) || 1107 construct<SectionSubscript>(intExpr)) 1108 1109 // R921 subscript-triplet -> [subscript] : [subscript] [: stride] 1110 TYPE_PARSER(construct<SubscriptTriplet>( 1111 maybe(subscript), ":" >> maybe(subscript), maybe(":" >> subscript))) 1112 1113 // R925 cosubscript -> scalar-int-expr 1114 constexpr auto cosubscript{scalarIntExpr}; 1115 1116 // R924 image-selector -> 1117 // lbracket cosubscript-list [, image-selector-spec-list] rbracket 1118 TYPE_CONTEXT_PARSER("image selector"_en_US, 1119 construct<ImageSelector>( 1120 "[" >> nonemptyList(cosubscript / lookAhead(space / ",]"_ch)), 1121 defaulted("," >> nonemptyList(Parser<ImageSelectorSpec>{})) / "]")) 1122 1123 // R926 image-selector-spec -> 1124 // STAT = stat-variable | TEAM = team-value | 1125 // TEAM_NUMBER = scalar-int-expr 1126 TYPE_PARSER(construct<ImageSelectorSpec>(construct<ImageSelectorSpec::Stat>( 1127 "STAT =" >> scalar(integer(indirect(variable))))) || 1128 construct<ImageSelectorSpec>(construct<TeamValue>("TEAM =" >> teamValue)) || 1129 construct<ImageSelectorSpec>(construct<ImageSelectorSpec::Team_Number>( 1130 "TEAM_NUMBER =" >> scalarIntExpr))) 1131 1132 // R927 allocate-stmt -> 1133 // ALLOCATE ( [type-spec ::] allocation-list [, alloc-opt-list] ) 1134 TYPE_CONTEXT_PARSER("ALLOCATE statement"_en_US, 1135 construct<AllocateStmt>("ALLOCATE (" >> maybe(typeSpec / "::"), 1136 nonemptyList(Parser<Allocation>{}), 1137 defaulted("," >> nonemptyList(Parser<AllocOpt>{})) / ")")) 1138 1139 // R928 alloc-opt -> 1140 // ERRMSG = errmsg-variable | MOLD = source-expr | 1141 // SOURCE = source-expr | STAT = stat-variable 1142 // R931 source-expr -> expr 1143 TYPE_PARSER(construct<AllocOpt>( 1144 construct<AllocOpt::Mold>("MOLD =" >> indirect(expr))) || 1145 construct<AllocOpt>( 1146 construct<AllocOpt::Source>("SOURCE =" >> indirect(expr))) || 1147 construct<AllocOpt>(statOrErrmsg)) 1148 1149 // R929 stat-variable -> scalar-int-variable 1150 TYPE_PARSER(construct<StatVariable>(scalar(integer(variable)))) 1151 1152 // R932 allocation -> 1153 // allocate-object [( allocate-shape-spec-list )] 1154 // [lbracket allocate-coarray-spec rbracket] 1155 TYPE_PARSER(construct<Allocation>(Parser<AllocateObject>{}, 1156 defaulted(parenthesized(nonemptyList(Parser<AllocateShapeSpec>{}))), 1157 maybe(bracketed(Parser<AllocateCoarraySpec>{})))) 1158 1159 // R933 allocate-object -> variable-name | structure-component 1160 TYPE_PARSER(construct<AllocateObject>(structureComponent) || 1161 construct<AllocateObject>(name / !"="_tok)) 1162 1163 // R934 allocate-shape-spec -> [lower-bound-expr :] upper-bound-expr 1164 // R938 allocate-coshape-spec -> [lower-bound-expr :] upper-bound-expr 1165 TYPE_PARSER(construct<AllocateShapeSpec>(maybe(boundExpr / ":"), boundExpr)) 1166 1167 // R937 allocate-coarray-spec -> 1168 // [allocate-coshape-spec-list ,] [lower-bound-expr :] * 1169 TYPE_PARSER(construct<AllocateCoarraySpec>( 1170 defaulted(nonemptyList(Parser<AllocateShapeSpec>{}) / ","), 1171 maybe(boundExpr / ":") / "*")) 1172 1173 // R939 nullify-stmt -> NULLIFY ( pointer-object-list ) 1174 TYPE_CONTEXT_PARSER("NULLIFY statement"_en_US, 1175 "NULLIFY" >> parenthesized(construct<NullifyStmt>( 1176 nonemptyList(Parser<PointerObject>{})))) 1177 1178 // R940 pointer-object -> 1179 // variable-name | structure-component | proc-pointer-name 1180 TYPE_PARSER(construct<PointerObject>(structureComponent) || 1181 construct<PointerObject>(name)) 1182 1183 // R941 deallocate-stmt -> 1184 // DEALLOCATE ( allocate-object-list [, dealloc-opt-list] ) 1185 TYPE_CONTEXT_PARSER("DEALLOCATE statement"_en_US, 1186 construct<DeallocateStmt>( 1187 "DEALLOCATE (" >> nonemptyList(Parser<AllocateObject>{}), 1188 defaulted("," >> nonemptyList(statOrErrmsg)) / ")")) 1189 1190 // R942 dealloc-opt -> STAT = stat-variable | ERRMSG = errmsg-variable 1191 // R1165 sync-stat -> STAT = stat-variable | ERRMSG = errmsg-variable 1192 TYPE_PARSER(construct<StatOrErrmsg>("STAT =" >> statVariable) || 1193 construct<StatOrErrmsg>("ERRMSG =" >> msgVariable)) 1194 1195 // Directives, extensions, and deprecated statements 1196 // !DIR$ IGNORE_TKR [ [(tkr...)] name ]... 1197 // !DIR$ name... 1198 constexpr auto beginDirective{skipStuffBeforeStatement >> "!"_ch}; 1199 constexpr auto endDirective{space >> endOfLine}; 1200 constexpr auto ignore_tkr{ 1201 "DIR$ IGNORE_TKR" >> optionalList(construct<CompilerDirective::IgnoreTKR>( 1202 defaulted(parenthesized(some("tkr"_ch))), name))}; 1203 TYPE_PARSER(beginDirective >> 1204 sourced(construct<CompilerDirective>(ignore_tkr) || 1205 construct<CompilerDirective>( 1206 "DIR$" >> many(construct<CompilerDirective::NameValue>(name, 1207 maybe(("="_tok || ":"_tok) >> digitString64))))) / 1208 endDirective) 1209 1210 TYPE_PARSER(extension<LanguageFeature::CrayPointer>( 1211 "nonstandard usage: based POINTER"_port_en_US, 1212 construct<BasedPointerStmt>( 1213 "POINTER" >> nonemptyList("expected POINTER associations"_err_en_US, 1214 construct<BasedPointer>("(" >> objectName / ",", 1215 objectName, maybe(Parser<ArraySpec>{}) / ")"))))) 1216 1217 // Subtle: the name includes the surrounding slashes, which avoids 1218 // clashes with other uses of the name in the same scope. 1219 TYPE_PARSER(construct<StructureStmt>( 1220 "STRUCTURE" >> maybe(sourced("/" >> name / "/")), optionalList(entityDecl))) 1221 1222 constexpr auto nestedStructureDef{ 1223 CONTEXT_PARSER("nested STRUCTURE definition"_en_US, 1224 construct<StructureDef>(statement(NestedStructureStmt{}), 1225 many(Parser<StructureField>{}), 1226 statement(construct<StructureDef::EndStructureStmt>( 1227 "END STRUCTURE"_tok))))}; 1228 1229 TYPE_PARSER(construct<StructureField>(statement(StructureComponents{})) || 1230 construct<StructureField>(indirect(Parser<Union>{})) || 1231 construct<StructureField>(indirect(nestedStructureDef))) 1232 1233 TYPE_CONTEXT_PARSER("STRUCTURE definition"_en_US, 1234 extension<LanguageFeature::DECStructures>( 1235 "nonstandard usage: STRUCTURE"_port_en_US, 1236 construct<StructureDef>(statement(Parser<StructureStmt>{}), 1237 many(Parser<StructureField>{}), 1238 statement(construct<StructureDef::EndStructureStmt>( 1239 "END STRUCTURE"_tok))))) 1240 1241 TYPE_CONTEXT_PARSER("UNION definition"_en_US, 1242 construct<Union>(statement(construct<Union::UnionStmt>("UNION"_tok)), 1243 many(Parser<Map>{}), 1244 statement(construct<Union::EndUnionStmt>("END UNION"_tok)))) 1245 1246 TYPE_CONTEXT_PARSER("MAP definition"_en_US, 1247 construct<Map>(statement(construct<Map::MapStmt>("MAP"_tok)), 1248 many(Parser<StructureField>{}), 1249 statement(construct<Map::EndMapStmt>("END MAP"_tok)))) 1250 1251 TYPE_CONTEXT_PARSER("arithmetic IF statement"_en_US, 1252 deprecated<LanguageFeature::ArithmeticIF>(construct<ArithmeticIfStmt>( 1253 "IF" >> parenthesized(expr), label / ",", label / ",", label))) 1254 1255 TYPE_CONTEXT_PARSER("ASSIGN statement"_en_US, 1256 deprecated<LanguageFeature::Assign>( 1257 construct<AssignStmt>("ASSIGN" >> label, "TO" >> name))) 1258 1259 TYPE_CONTEXT_PARSER("assigned GOTO statement"_en_US, 1260 deprecated<LanguageFeature::AssignedGOTO>(construct<AssignedGotoStmt>( 1261 "GO TO" >> name, 1262 defaulted(maybe(","_tok) >> 1263 parenthesized(nonemptyList("expected labels"_err_en_US, label)))))) 1264 1265 TYPE_CONTEXT_PARSER("PAUSE statement"_en_US, 1266 deprecated<LanguageFeature::Pause>( 1267 construct<PauseStmt>("PAUSE" >> maybe(Parser<StopCode>{})))) 1268 1269 // These requirement productions are defined by the Fortran standard but never 1270 // used directly by the grammar: 1271 // R620 delimiter -> ( | ) | / | [ | ] | (/ | /) 1272 // R1027 numeric-expr -> expr 1273 // R1031 int-constant-expr -> int-expr 1274 // R1221 dtv-type-spec -> TYPE ( derived-type-spec ) | 1275 // CLASS ( derived-type-spec ) 1276 // 1277 // These requirement productions are defined and used, but need not be 1278 // defined independently here in this file: 1279 // R771 lbracket -> [ 1280 // R772 rbracket -> ] 1281 // 1282 // Further note that: 1283 // R607 int-constant -> constant 1284 // is used only once via R844 scalar-int-constant 1285 // R904 logical-variable -> variable 1286 // is used only via scalar-logical-variable 1287 // R906 default-char-variable -> variable 1288 // is used only via scalar-default-char-variable 1289 // R907 int-variable -> variable 1290 // is used only via scalar-int-variable 1291 // R915 complex-part-designator -> designator % RE | designator % IM 1292 // %RE and %IM are initially recognized as structure components 1293 // R916 type-param-inquiry -> designator % type-param-name 1294 // is occulted by structure component designators 1295 // R918 array-section -> 1296 // data-ref [( substring-range )] | complex-part-designator 1297 // is not used because parsing is not sensitive to rank 1298 // R1030 default-char-constant-expr -> default-char-expr 1299 // is only used via scalar-default-char-constant-expr 1300 } // namespace Fortran::parser 1301