| -- |
| -- m2.bnf grammar and associated actions for pass 0. |
| -- |
| -- Copyright (C) 2001-2025 Free Software Foundation, Inc. |
| -- Contributed by Gaius Mulley <gaius.mulley@southwales.ac.uk>. |
| -- |
| -- This file is part of GNU Modula-2. |
| -- |
| -- GNU Modula-2 is free software; you can redistribute it and/or modify |
| -- it under the terms of the GNU General Public License as published by |
| -- the Free Software Foundation; either version 3, or (at your option) |
| -- any later version. |
| -- |
| -- GNU Modula-2 is distributed in the hope that it will be useful, but |
| -- WITHOUT ANY WARRANTY; without even the implied warranty of |
| -- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| -- General Public License for more details. |
| -- |
| -- You should have received a copy of the GNU General Public License |
| -- along with GNU Modula-2; see the file COPYING3. If not see |
| -- <http://www.gnu.org/licenses/>. |
| % module P0SyntaxCheck begin |
| (* output from m2.bnf, automatically generated do not edit if these |
| are the top two lines in the file. |
| |
| Copyright (C) 2001-2025 Free Software Foundation, Inc. |
| Contributed by Gaius Mulley <gaius.mulley@southwales.ac.uk>. |
| |
| This file is part of GNU Modula-2. |
| |
| GNU Modula-2 is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 3, or (at your option) |
| any later version. |
| |
| GNU Modula-2 is distributed in the hope that it will be useful, but |
| WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GNU Modula-2; see the file COPYING. If not, |
| see <https://www.gnu.org/licenses/>. *) |
| |
| IMPLEMENTATION MODULE P0SyntaxCheck ; |
| |
| FROM M2LexBuf IMPORT currentstring, currenttoken, GetToken, InsertToken, |
| InsertTokenAndRewind, GetTokenNo, DisplayToken, DumpTokens ; |
| |
| FROM M2Quads IMPORT PushT, PushTF, IsAutoPushOn, PushAutoOff, PushAutoOn, |
| PopAuto, DisplayStack, PushTFtok, PushTtok, DupFrame, |
| Top ; |
| |
| FROM M2Reserved IMPORT tokToTok, toktype, NulTok, ImportTok, ExportTok, |
| QualifiedTok, UnQualifiedTok, BuiltinTok, InlineTok ; |
| |
| FROM M2MetaError IMPORT MetaErrorStringT0 ; |
| FROM P2SymBuild IMPORT BuildString, BuildNumber ; |
| FROM NameKey IMPORT Name, NulName, makekey ; |
| FROM StrLib IMPORT StrCopy, StrConCat, StrEqual ; |
| FROM M2Batch IMPORT MakeProgramSource, MakeDefinitionSource, MakeImplementationSource ; |
| FROM DynamicStrings IMPORT String, InitString, KillString, Mark, ConCat, ConCatChar ; |
| FROM M2Debug IMPORT Assert ; |
| FROM M2Printf IMPORT printf0 ; |
| |
| (* imports for Pass0 *) |
| |
| FROM P0SymBuild IMPORT RegisterImports, RegisterInnerImports, |
| RegisterProgramModule, |
| RegisterImplementationModule, RegisterDefinitionModule, |
| RegisterInnerModule, EndModule, |
| RegisterProcedure, EndProcedure, EndForward ; |
| |
| FROM SymbolTable IMPORT NulSym, PutModuleContainsBuiltin, PutHiddenTypeDeclared ; |
| |
| IMPORT M2Error ; |
| |
| |
| CONST |
| Debugging = FALSE ; |
| DebugRecover = FALSE ; |
| Pass0 = TRUE ; |
| Pass1 = FALSE ; |
| Pass2 = FALSE ; (* permanently disabled for the time being *) |
| Pass3 = FALSE ; (* permanently disabled for the time being *) |
| MaxInsert = 10 ; (* allow 10 tokens to be inserted before *) |
| (* giving up. *) |
| |
| VAR |
| EnableImportCheck, |
| seenError : BOOLEAN ; |
| LastIdent : Name ; |
| InsertCount : CARDINAL ; |
| |
| |
| (* |
| BlockAssert - wrap an Assert specifically for blocks. |
| *) |
| |
| PROCEDURE BlockAssert (value: BOOLEAN) ; |
| BEGIN |
| Assert (value) ; |
| END BlockAssert ; |
| |
| |
| PROCEDURE ErrorString (s: String) ; |
| BEGIN |
| MetaErrorStringT0 (GetTokenNo (), s) ; |
| seenError := TRUE |
| END ErrorString ; |
| |
| |
| PROCEDURE ErrorArray (a: ARRAY OF CHAR) ; |
| BEGIN |
| ErrorString (InitString (a)) |
| END ErrorArray ; |
| |
| |
| % declaration P0SyntaxCheck begin |
| |
| (* |
| SyntaxError - after a syntax error we skip all tokens up until we reach |
| a stop symbol. |
| *) |
| |
| PROCEDURE SyntaxError (stopset0: SetOfStop0; stopset1: SetOfStop1; stopset2: SetOfStop2) ; |
| BEGIN |
| DescribeError ; |
| IF Debugging |
| THEN |
| printf0('\nskipping token *** ') |
| END ; |
| (* --fixme-- this assumes a 32 bit word size. *) |
| WHILE NOT (((ORD(currenttoken)<32) AND (currenttoken IN stopset0)) OR |
| ((ORD(currenttoken)>=32) AND (ORD(currenttoken)<64) AND (currenttoken IN stopset1)) OR |
| ((ORD(currenttoken)>=64) AND (currenttoken IN stopset2))) |
| DO |
| GetToken |
| END ; |
| IF Debugging |
| THEN |
| printf0(' ***\n') |
| END |
| END SyntaxError ; |
| |
| |
| (* |
| SyntaxCheck - |
| *) |
| |
| PROCEDURE SyntaxCheck (stopset0: SetOfStop0; stopset1: SetOfStop1; stopset2: SetOfStop2) ; |
| BEGIN |
| (* --fixme-- this assumes a 32 bit word size. *) |
| IF NOT (((ORD(currenttoken)<32) AND (currenttoken IN stopset0)) OR |
| ((ORD(currenttoken)>=32) AND (ORD(currenttoken)<64) AND (currenttoken IN stopset1)) OR |
| ((ORD(currenttoken)>=64) AND (currenttoken IN stopset2))) |
| THEN |
| SyntaxError (stopset0, stopset1, stopset2) |
| END |
| END SyntaxCheck ; |
| |
| |
| (* |
| GetMissingTokenMessage - generates and returns a string about a missing token, t. |
| *) |
| |
| PROCEDURE GetMissingTokenMessage (t: toktype) : String ; |
| VAR |
| s0 : SetOfStop0 ; |
| s1 : SetOfStop1 ; |
| s2 : SetOfStop2 ; |
| str: String ; |
| BEGIN |
| s0 := SetOfStop0{} ; |
| s1 := SetOfStop1{} ; |
| s2 := SetOfStop2{} ; |
| IF ORD(t)<32 |
| THEN |
| s0 := SetOfStop0{t} |
| ELSIF ORD(t)<64 |
| THEN |
| s1 := SetOfStop1{t} |
| ELSE |
| s2 := SetOfStop2{t} |
| END ; |
| str := DescribeStop (s0, s1, s2) ; |
| RETURN str |
| END GetMissingTokenMessage ; |
| |
| |
| (* |
| ErrorMissingToken - generates an error message about a missing token, t. |
| *) |
| |
| PROCEDURE ErrorMissingToken (t: toktype) ; |
| VAR |
| str: String ; |
| BEGIN |
| str := GetMissingTokenMessage (t) ; |
| str := ConCat (InitString ('syntax error,'), Mark (str)) ; |
| MetaErrorStringT0 (GetTokenNo (), str) |
| END ErrorMissingToken ; |
| |
| |
| (* |
| WarnMissingToken - generates a warning message about a missing token, t. |
| *) |
| |
| PROCEDURE WarnMissingToken (t: toktype) ; |
| VAR |
| str: String ; |
| BEGIN |
| str := GetMissingTokenMessage (t) ; |
| str := ConCat (InitString ('{%W}syntax warning,'), Mark (str)) ; |
| MetaErrorStringT0 (GetTokenNo (), str) ; |
| IF DebugRecover |
| THEN |
| printf0 ("warning note created\n") |
| END |
| END WarnMissingToken ; |
| |
| |
| (* |
| MissingToken - generates a warning message about a missing token, t. |
| *) |
| |
| PROCEDURE MissingToken (t: toktype) ; |
| BEGIN |
| IF (InsertCount<MaxInsert) AND |
| ((t#identtok) AND (t#integertok) AND (t#realtok) AND (t#stringtok)) |
| THEN |
| IF DebugRecover |
| THEN |
| printf0 ("missing token detected and going to be inserted: "); |
| DisplayToken (t) |
| END ; |
| WarnMissingToken (t) ; |
| INC (InsertCount) ; |
| IF DebugRecover |
| THEN |
| printf0 ('inserting token\n') |
| END ; |
| InsertToken (t) |
| ELSE |
| IF DebugRecover |
| THEN |
| printf0 ("missing token detected but cannot be inserted: "); |
| DisplayToken (t) |
| END ; |
| ErrorMissingToken (t) |
| END |
| END MissingToken ; |
| |
| |
| (* |
| CheckInsertCandidate - |
| *) |
| |
| PROCEDURE CheckInsertCandidate (t: toktype; stopset0: SetOfStop0; stopset1: SetOfStop1; stopset2: SetOfStop2) : BOOLEAN ; |
| BEGIN |
| IF ((ORD(t)<32) AND (t IN stopset0)) OR |
| ((ORD(t)>=32) AND (ORD(t)<64) AND (t IN stopset1)) OR |
| ((ORD(t)>=64) AND (t IN stopset2)) |
| THEN |
| INC (InsertCount) ; |
| IF InsertCount < MaxInsert |
| THEN |
| WarnMissingToken (t) ; |
| IF DebugRecover |
| THEN |
| printf0 ('buffer before\n') ; |
| DumpTokens |
| END ; |
| InsertTokenAndRewind (t) ; |
| IF DebugRecover |
| THEN |
| printf0 ('inserting token: buffer after insertion\n') ; |
| DumpTokens |
| END ; |
| RETURN TRUE |
| END |
| END ; |
| RETURN FALSE |
| END CheckInsertCandidate ; |
| |
| |
| (* |
| InStopSet |
| *) |
| |
| PROCEDURE InStopSet (t: toktype; stopset0: SetOfStop0; stopset1: SetOfStop1; stopset2: SetOfStop2) : BOOLEAN ; |
| BEGIN |
| IF ((ORD(t)<32) AND (t IN stopset0)) OR |
| ((ORD(t)>=32) AND (ORD(t)<64) AND (t IN stopset1)) OR |
| ((ORD(t)>=64) AND (t IN stopset2)) |
| THEN |
| RETURN( TRUE ) |
| ELSE |
| RETURN( FALSE ) |
| END |
| END InStopSet ; |
| |
| |
| (* |
| PeepToken - peep token checks to see whether the stopset is satisfied by currenttoken |
| If it is not then it will insert a token providing the token |
| is one of ; ] ) } . OF END , |
| |
| if the stopset contains <identtok> then we do not insert a token |
| *) |
| |
| PROCEDURE PeepToken (stopset0: SetOfStop0; stopset1: SetOfStop1; stopset2: SetOfStop2) ; |
| BEGIN |
| (* and again (see above re: ORD) |
| *) |
| IF (NOT (((ORD(currenttoken)<32) AND (currenttoken IN stopset0)) OR |
| ((ORD(currenttoken)>=32) AND (ORD(currenttoken)<64) AND (currenttoken IN stopset1)) OR |
| ((ORD(currenttoken)>=64) AND (currenttoken IN stopset2)))) AND |
| (NOT InStopSet(identtok, stopset0, stopset1, stopset2)) |
| THEN |
| (* SyntaxCheck will fail since currentoken is not part of the stopset |
| we check to see whether one of the following is in the stopset and |
| if not emit a warning and also the token. *) |
| IF CheckInsertCandidate (semicolontok, stopset0, stopset1, stopset2) OR |
| CheckInsertCandidate (rsbratok, stopset0, stopset1, stopset2) OR |
| CheckInsertCandidate (rparatok, stopset0, stopset1, stopset2) OR |
| CheckInsertCandidate (rcbratok, stopset0, stopset1, stopset2) OR |
| CheckInsertCandidate (periodtok, stopset0, stopset1, stopset2) OR |
| CheckInsertCandidate (oftok, stopset0, stopset1, stopset2) OR |
| CheckInsertCandidate (endtok, stopset0, stopset1, stopset2) OR |
| CheckInsertCandidate (commatok, stopset0, stopset1, stopset2) |
| THEN |
| END |
| END |
| END PeepToken ; |
| |
| |
| (* |
| DetectImport - checks whether the next token is an import or from and if so |
| generates an error message. This is called after an export |
| statement to notify the user that the ordering is incorrect. |
| *) |
| |
| PROCEDURE DetectImport ; |
| BEGIN |
| IF (currenttoken = importtok) OR (currenttoken = fromtok) |
| THEN |
| ErrorArray ('an {%AkIMPORT} statement must preceed an {%kEXPORT} statement') |
| END |
| END DetectImport ; |
| |
| |
| (* |
| Expect - |
| *) |
| |
| PROCEDURE Expect (t: toktype; stopset0: SetOfStop0; stopset1: SetOfStop1; stopset2: SetOfStop2) ; |
| BEGIN |
| IF currenttoken=t |
| THEN |
| GetToken ; |
| IF EnableImportCheck |
| THEN |
| DetectImport |
| END ; |
| IF Pass0 |
| THEN |
| PeepToken (stopset0, stopset1, stopset2) |
| END |
| ELSE |
| MissingToken (t) |
| END ; |
| SyntaxCheck (stopset0, stopset1, stopset2) |
| END Expect ; |
| |
| |
| (* |
| CompilationUnit - returns TRUE if the input was correct enough to parse |
| in future passes. |
| *) |
| |
| PROCEDURE CompilationUnit () : BOOLEAN ; |
| BEGIN |
| seenError := FALSE ; |
| EnableImportCheck := FALSE ; |
| InsertCount := 0 ; |
| FileUnit (SetOfStop0{eoftok}, SetOfStop1{}, SetOfStop2{}) ; |
| RETURN NOT seenError |
| END CompilationUnit ; |
| |
| |
| (* |
| Ident - error checking varient of Ident |
| *) |
| |
| PROCEDURE Ident (stopset0: SetOfStop0; stopset1: SetOfStop1; stopset2: SetOfStop2) ; |
| BEGIN |
| LastIdent := makekey (currentstring) ; |
| IF IsAutoPushOn () |
| THEN |
| PushTFtok (LastIdent, identtok, GetTokenNo()) |
| END ; |
| Expect (identtok, stopset0, stopset1, stopset2) |
| END Ident ; |
| |
| |
| (* |
| string - |
| *) |
| |
| PROCEDURE string (stopset0: SetOfStop0; stopset1: SetOfStop1; stopset2: SetOfStop2) ; |
| BEGIN |
| IF IsAutoPushOn () |
| THEN |
| PushTF (makekey (currentstring), stringtok) ; |
| BuildString |
| END ; |
| Expect (stringtok, stopset0, stopset1, stopset2) |
| END string ; |
| |
| |
| (* |
| Integer - |
| *) |
| |
| PROCEDURE Integer (stopset0: SetOfStop0; stopset1: SetOfStop1; stopset2: SetOfStop2) ; |
| BEGIN |
| IF IsAutoPushOn() |
| THEN |
| PushTFtok (makekey (currentstring), integertok, GetTokenNo ()) ; |
| BuildNumber |
| END ; |
| Expect(integertok, stopset0, stopset1, stopset2) |
| END Integer ; |
| |
| |
| (* |
| Real - |
| *) |
| |
| PROCEDURE Real (stopset0: SetOfStop0; stopset1: SetOfStop1; stopset2: SetOfStop2) ; |
| BEGIN |
| IF IsAutoPushOn() |
| THEN |
| PushTFtok (makekey (currentstring), realtok, GetTokenNo ()) ; |
| BuildNumber |
| END ; |
| Expect(realtok, stopset0, stopset1, stopset2) |
| END Real ; |
| |
| % module P0SyntaxCheck end |
| END P0SyntaxCheck. |
| % rules |
| error 'ErrorArray' 'ErrorString' |
| tokenfunc 'currenttoken' |
| |
| token '' eoftok -- internal token |
| token '+' plustok |
| token '-' minustok |
| token '*' timestok |
| token '/' dividetok |
| token ':=' becomestok |
| token '&' ambersandtok |
| token "." periodtok |
| token "," commatok |
| token ";" semicolontok |
| token '(' lparatok |
| token ')' rparatok |
| token '[' lsbratok -- left square brackets |
| token ']' rsbratok -- right square brackets |
| token '{' lcbratok -- left curly brackets |
| token '}' rcbratok -- right curly brackets |
| token '^' uparrowtok |
| token "'" singlequotetok |
| token '=' equaltok |
| token '#' hashtok |
| token '<' lesstok |
| token '>' greatertok |
| token '<>' lessgreatertok |
| token '<=' lessequaltok |
| token '>=' greaterequaltok |
| token '<*' ldirectivetok |
| token '*>' rdirectivetok |
| token '..' periodperiodtok |
| token ':' colontok |
| token '"' doublequotestok |
| token '|' bartok |
| token 'AND' andtok |
| token 'ARRAY' arraytok |
| token 'BEGIN' begintok |
| token 'BY' bytok |
| token 'CASE' casetok |
| token 'CONST' consttok |
| token 'DEFINITION' definitiontok |
| token 'DIV' divtok |
| token 'DO' dotok |
| token 'ELSE' elsetok |
| token 'ELSIF' elsiftok |
| token 'END' endtok |
| token 'EXCEPT' excepttok |
| token 'EXIT' exittok |
| token 'EXPORT' exporttok |
| token 'FINALLY' finallytok |
| token 'FOR' fortok |
| token 'FORWARD' forwardtok |
| token 'FROM' fromtok |
| token 'IF' iftok |
| token 'IMPLEMENTATION' implementationtok |
| token 'IMPORT' importtok |
| token 'IN' intok |
| token 'LOOP' looptok |
| token 'MOD' modtok |
| token 'MODULE' moduletok |
| token 'NOT' nottok |
| token 'OF' oftok |
| token 'OR' ortok |
| token 'PACKEDSET' packedsettok |
| token 'POINTER' pointertok |
| token 'PROCEDURE' proceduretok |
| token 'QUALIFIED' qualifiedtok |
| token 'UNQUALIFIED' unqualifiedtok |
| token 'RECORD' recordtok |
| token 'REM' remtok |
| token 'REPEAT' repeattok |
| token 'RETRY' retrytok |
| token 'RETURN' returntok |
| token 'SET' settok |
| token 'THEN' thentok |
| token 'TO' totok |
| token 'TYPE' typetok |
| token 'UNTIL' untiltok |
| token 'VAR' vartok |
| token 'WHILE' whiletok |
| token 'WITH' withtok |
| token 'ASM' asmtok |
| token 'VOLATILE' volatiletok |
| token '...' periodperiodperiodtok |
| token '__DATE__' datetok |
| token '__LINE__' linetok |
| token '__FILE__' filetok |
| token '__ATTRIBUTE__' attributetok |
| token '__BUILTIN__' builtintok |
| token '__INLINE__' inlinetok |
| token 'integer number' integertok |
| token 'identifier' identtok |
| token 'real number' realtok |
| token 'string' stringtok |
| |
| special Ident first { < identtok > } follow { } |
| '@i{is a builtin and checks for an identifier}' |
| special Integer first { < integertok > } follow { } |
| '@i{is a builtin and checks for an integer}' |
| special Real first { < realtok > } follow { } |
| '@i{is a builtin and checks for an real constant}' |
| special string first { < stringtok > } follow { } |
| '@i{is a builtin and checks for an string constant}' |
| BNF |
| |
| -- the following are provided by the module m2flex and also hand built procedures below |
| -- Ident := Letter { ( Letter | Digit ) } =: |
| -- Integer := Digit { Digit } | OctalDigit { OctalDigit } ( " B " | " C " ) | |
| -- Digit { HexDigit } " H " =: |
| -- Real := Digit { Digit } " . " { Digit } [ ScaleFactor ] =: |
| -- ScaleFactor := " E " [ ( " + " | " - " ) ] Digit { Digit } =: |
| -- HexDigit := Digit | " A " | " B " | " C " | " D " | " E " | " F " =: |
| -- Digit := OctalDigit | " 8 " | " 9 " =: |
| -- OctalDigit := "0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" =: |
| -- String |
| |
| FileUnit := % PushAutoOff % |
| ( DefinitionModule | ImplementationOrProgramModule ) % PopAuto % |
| =: |
| |
| ProgramModule := "MODULE" % PushAutoOn ; % |
| % M2Error.DefaultProgramModule % |
| Ident % RegisterProgramModule ; % |
| % PushAutoOff ; % |
| [ Priority ] |
| ";" |
| % PushAutoOn ; % |
| { Import % RegisterImports % |
| } % PopAuto % |
| Block % PopAuto % |
| Ident "." % EndModule % |
| % PopAuto % |
| =: |
| |
| ImplementationModule := "IMPLEMENTATION" % M2Error.DefaultImplementationModule % |
| "MODULE" % PushAutoOn ; % |
| Ident % RegisterImplementationModule ; % |
| % PushAutoOff ; % |
| [ Priority ] ";" % PushAutoOn ; % |
| { Import % RegisterImports % |
| } % PopAuto % |
| Block % PopAuto % |
| |
| Ident % EndModule % |
| % PopAuto % |
| "." =: |
| |
| ImplementationOrProgramModule := ImplementationModule | ProgramModule =: |
| |
| Number := Integer | Real =: |
| |
| Qualident := Ident { "." Ident } =: |
| |
| ConstantDeclaration := Ident "=" ConstExpression =: |
| |
| ConstExpression := SimpleConstExpr [ Relation SimpleConstExpr ] =: |
| |
| Relation := "=" | "#" | "<>" | "<" | "<=" | ">" | ">=" | "IN" =: |
| |
| SimpleConstExpr := UnaryOrConstTerm { AddOperator ConstTerm } =: |
| |
| UnaryOrConstTerm := "+" ConstTerm | "-" ConstTerm | ConstTerm =: |
| |
| AddOperator := "+" | "-" | "OR" =: |
| |
| ConstTerm := ConstFactor { MulOperator ConstFactor } =: |
| |
| MulOperator := "*" | "/" | "DIV" | "MOD" | "REM" | "AND" | "&" =: |
| |
| ConstFactor := Number | ConstString | ConstSetOrQualidentOrFunction | |
| "(" ConstExpression ")" | "NOT" ConstFactor | |
| ConstAttribute =: |
| |
| -- to help satisfy LL1 |
| |
| ConstString := string =: |
| |
| ComponentElement := ConstExpression [ ".." ConstExpression ] =: |
| |
| ComponentValue := ComponentElement [ 'BY' ConstExpression ] =: |
| |
| ArraySetRecordValue := ComponentValue { ',' ComponentValue } =: |
| |
| Constructor := '{' [ ArraySetRecordValue ] '}' =: |
| |
| ConstSetOrQualidentOrFunction := Constructor | Qualident |
| [ Constructor | ConstActualParameters ] =: |
| |
| ConstActualParameters := "(" [ ExpList ] ")" =: |
| |
| ConstAttribute := "__ATTRIBUTE__" "__BUILTIN__" "(" "(" ConstAttributeExpression ")" ")" =: |
| |
| ConstAttributeExpression := Ident | "<" Qualident ',' Ident ">" =: |
| |
| ByteAlignment := '<*' AttributeExpression '*>' =: |
| |
| -- AlignmentExpression := "(" ConstExpression ")" =: |
| |
| Alignment := [ ByteAlignment ] =: |
| |
| TypeDeclaration := Ident "=" Type Alignment =: |
| |
| Type := SimpleType | ArrayType | RecordType | SetType | |
| PointerType | ProcedureType =: |
| |
| SimpleType := Qualident [ SubrangeType ] | Enumeration | SubrangeType =: |
| |
| Enumeration := "(" IdentList ")" =: |
| |
| IdentList := Ident % VAR |
| on: BOOLEAN ; |
| n : CARDINAL ; % |
| % on := IsAutoPushOn() ; |
| IF on |
| THEN |
| n := 1 |
| END % |
| { "," Ident % IF on |
| THEN |
| INC(n) |
| END % |
| } % IF on |
| THEN |
| PushT(n) |
| END % |
| =: |
| |
| SubrangeType := "[" ConstExpression ".." ConstExpression "]" =: |
| |
| ArrayType := "ARRAY" SimpleType { "," SimpleType } "OF" Type =: |
| |
| RecordType := "RECORD" [ DefaultRecordAttributes ] FieldListSequence "END" =: |
| |
| DefaultRecordAttributes := '<*' AttributeExpression '*>' =: |
| |
| RecordFieldPragma := [ '<*' FieldPragmaExpression |
| { ',' FieldPragmaExpression } '*>' ] =: |
| |
| FieldPragmaExpression := Ident [ '(' ConstExpression ')' ] =: |
| |
| AttributeExpression := Ident '(' ConstExpression ')' =: |
| |
| FieldListSequence := FieldListStatement { ";" FieldListStatement } =: |
| |
| FieldListStatement := [ FieldList ] =: |
| |
| FieldList := IdentList ":" Type RecordFieldPragma |
| | |
| "CASE" CaseTag "OF" Varient { "|" Varient } |
| [ "ELSE" FieldListSequence ] "END" |
| =: |
| |
| TagIdent := [ Ident ] =: |
| |
| CaseTag := TagIdent [ ":" Qualident ] =: |
| |
| Varient := [ VarientCaseLabelList ":" FieldListSequence ] =: |
| |
| VarientCaseLabelList := VarientCaseLabels { "," VarientCaseLabels } =: |
| |
| VarientCaseLabels := ConstExpression [ ".." ConstExpression ] =: |
| |
| CaseLabelList := CaseLabels { "," CaseLabels } =: |
| |
| CaseLabels := ConstExpression [ ".." ConstExpression ] =: |
| |
| SetType := ( "SET" | "PACKEDSET" ) "OF" SimpleType =: |
| |
| PointerType := "POINTER" "TO" Type =: |
| |
| ProcedureType := "PROCEDURE" [ FormalTypeList ] =: |
| |
| FormalTypeList := "(" ( ")" FormalReturn | |
| ProcedureParameters ")" FormalReturn ) =: |
| |
| FormalReturn := [ ":" OptReturnType ] =: |
| |
| OptReturnType := "[" Qualident "]" | Qualident =: |
| |
| ProcedureParameters := ProcedureParameter |
| { "," ProcedureParameter } =: |
| |
| ProcedureParameter := "..." | "VAR" FormalType | FormalType =: |
| |
| VarIdent := Ident [ "[" ConstExpression "]" ] |
| =: |
| |
| VariableDeclaration := VarIdentList ":" Type Alignment =: |
| |
| VarIdentList := VarIdent % VAR |
| on: BOOLEAN ; |
| n : CARDINAL ; % |
| % on := IsAutoPushOn() ; |
| IF on |
| THEN |
| n := 1 |
| END % |
| { "," VarIdent % IF on |
| THEN |
| INC(n) |
| END % |
| } % IF on |
| THEN |
| PushT(n) |
| END % |
| =: |
| |
| Designator := Qualident { SubDesignator } =: |
| |
| SubDesignator := "." Ident | "[" ExpList "]" | "^" =: |
| |
| ExpList := Expression { "," Expression } =: |
| |
| Expression := SimpleExpression [ Relation SimpleExpression ] =: |
| |
| SimpleExpression := [ "+" | "-" ] Term { AddOperator Term } =: |
| |
| Term := Factor { MulOperator Factor } =: |
| |
| Factor := Number | string | SetOrDesignatorOrFunction | |
| "(" Expression ")" | "NOT" Factor | ConstAttribute =: |
| |
| SetOrDesignatorOrFunction := ( Qualident [ Constructor | |
| SimpleDes [ ActualParameters ] |
| ] | Constructor |
| ) |
| =: |
| |
| SimpleDes := { "." Ident | "[" ExpList "]" | "^" } =: |
| |
| ActualParameters := "(" [ ExpList ] ")" =: |
| |
| Statement := [ AssignmentOrProcedureCall | IfStatement | CaseStatement | |
| WhileStatement | RepeatStatement | LoopStatement | |
| ForStatement | WithStatement | AsmStatement | |
| "EXIT" | "RETURN" [ Expression ] | RetryStatement ] =: |
| |
| RetryStatement := "RETRY" =: |
| |
| AssignmentOrProcedureCall := Designator ( ":=" Expression | |
| ActualParameters | % (* epsilon *) % |
| ) =: |
| |
| -- these two break LL1 as both start with a Designator |
| -- ProcedureCall := Designator [ ActualParameters ] =: |
| -- Assignment := Designator ":=" Expression =: |
| |
| StatementSequence := Statement { ";" Statement } =: |
| |
| IfStatement := "IF" Expression "THEN" StatementSequence |
| { "ELSIF" Expression "THEN" StatementSequence } |
| [ "ELSE" StatementSequence ] "END" =: |
| |
| CaseStatement := "CASE" Expression "OF" Case { "|" Case } |
| [ "ELSE" StatementSequence ] "END" =: |
| |
| Case := [ CaseLabelList ":" StatementSequence ] =: |
| |
| WhileStatement := "WHILE" Expression "DO" StatementSequence "END" =: |
| |
| RepeatStatement := "REPEAT" StatementSequence "UNTIL" Expression =: |
| |
| ForStatement := "FOR" Ident ":=" Expression "TO" Expression |
| [ "BY" ConstExpression ] "DO" |
| StatementSequence "END" =: |
| |
| LoopStatement := "LOOP" StatementSequence "END" =: |
| |
| WithStatement := "WITH" Designator "DO" StatementSequence "END" =: |
| |
| ProcedureDeclaration := % VAR top: CARDINAL ; % |
| % top := Top () % |
| ProcedureHeading ";" PostProcedureHeading % BlockAssert (top = Top ()) % |
| =: |
| |
| PostProcedureHeading := ProperProcedure | ForwardDeclaration =: |
| |
| ForwardDeclaration := "FORWARD" % EndForward % |
| =: |
| |
| ProperProcedure := ProcedureBlock % PushAutoOn % |
| Ident % EndProcedure % |
| % PopAuto % |
| =: |
| |
| DefineBuiltinProcedure := [ "__ATTRIBUTE__" "__BUILTIN__" "(" "(" Ident ")" ")" | |
| "__INLINE__" ] =: |
| |
| ProcedureHeading := "PROCEDURE" % M2Error.DefaultProcedure % |
| DefineBuiltinProcedure |
| ( % PushAutoOn % |
| Ident % RegisterProcedure % |
| % PopAuto % |
| [ FormalParameters ] AttributeNoReturn ) =: |
| |
| AttributeNoReturn := [ "<*" Ident "*>" ] =: |
| |
| AttributeUnused := [ "<*" Ident "*>" ] =: |
| |
| -- note that we do need to know whether builtins are used as they |
| -- determine whether we need to parse the implementation module |
| -- the same is true for hidden types |
| |
| Builtin := [ "__BUILTIN__" % PutModuleContainsBuiltin % |
| | "__INLINE__" ] =: |
| |
| DefProcedureHeading := "PROCEDURE" % M2Error.DefaultProcedure % |
| Builtin |
| ( Ident [ DefFormalParameters ] AttributeNoReturn ) |
| % M2Error.LeaveErrorScope % |
| =: |
| |
| -- introduced procedure block so we can produce more informative |
| -- error messages |
| |
| ProcedureBlock := { Declaration } [ "BEGIN" BlockBody ] "END" =: |
| |
| Block := { Declaration } InitialBlock FinalBlock "END" =: |
| |
| InitialBlock := [ "BEGIN" BlockBody ] =: |
| |
| FinalBlock := [ "FINALLY" BlockBody ] =: |
| |
| BlockBody := NormalPart [ "EXCEPT" ExceptionalPart ] =: |
| |
| NormalPart := StatementSequence =: |
| |
| ExceptionalPart := StatementSequence =: |
| |
| Declaration := "CONST" { ConstantDeclaration ";" } | |
| "TYPE" { TypeDeclaration ";" } | |
| "VAR" { VariableDeclaration ";" } | |
| ProcedureDeclaration ";" | |
| ModuleDeclaration ";" =: |
| |
| DefFormalParameters := "(" [ DefMultiFPSection ] ")" FormalReturn =: |
| |
| DefMultiFPSection := DefExtendedFP | |
| FPSection [ ";" DefMultiFPSection ] =: |
| |
| FormalParameters := "(" [ MultiFPSection ] ")" FormalReturn =: |
| |
| MultiFPSection := ExtendedFP | |
| FPSection [ ";" MultiFPSection ] =: |
| |
| FPSection := NonVarFPSection | VarFPSection =: |
| |
| DefExtendedFP := DefOptArg | "..." =: |
| |
| ExtendedFP := OptArg | "..." =: |
| |
| VarFPSection := "VAR" IdentList ":" FormalType [ AttributeUnused ] =: |
| |
| NonVarFPSection := IdentList ":" FormalType [ AttributeUnused ] =: |
| |
| OptArg := "[" Ident ":" FormalType [ "=" ConstExpression ] "]" =: |
| |
| DefOptArg := "[" Ident ":" FormalType "=" ConstExpression "]" =: |
| |
| FormalType := { "ARRAY" "OF" } Qualident =: |
| |
| ModuleDeclaration := "MODULE" % PushAutoOn % |
| % M2Error.DefaultInnerModule % |
| Ident % RegisterInnerModule % |
| % PushAutoOff % |
| [ Priority ] ";" % PushAutoOn % |
| { Import % RegisterInnerImports % |
| } % PopAuto % |
| [ Export ] Block % PopAuto % |
| Ident % EndModule % |
| % PopAuto % |
| =: |
| |
| Priority := "[" ConstExpression "]" =: |
| |
| Export := "EXPORT" ( "QUALIFIED" IdentList | |
| "UNQUALIFIED" IdentList | |
| IdentList |
| ) % EnableImportCheck := TRUE % |
| ";" % EnableImportCheck := FALSE % |
| =: |
| |
| Import := "FROM" Ident "IMPORT" IdentList ";" | |
| "IMPORT" % PushTtok (ImportTok, GetTokenNo () -1) |
| (* determines whether Ident or Module *) % |
| IdentList ";" =: |
| |
| DefinitionModule := % VAR forC: BOOLEAN ; % |
| % forC := FALSE % |
| "DEFINITION" % M2Error.DefaultDefinitionModule % |
| "MODULE" [ "FOR" string % forC := TRUE % |
| ] % PushAutoOn % |
| Ident % RegisterDefinitionModule (forC) % |
| ";" |
| { Import % RegisterImports % |
| } % PushAutoOff % |
| [ Export |
| ] |
| { Definition } % PopAuto % |
| "END" Ident % EndModule % |
| "." % PopAuto % |
| =: |
| |
| Definition := "CONST" { ConstantDeclaration ";" } | |
| "TYPE" { Ident |
| ( ";" % PutHiddenTypeDeclared % |
| | "=" Type Alignment ";" ) } |
| | |
| "VAR" { VariableDeclaration ";" } | |
| DefProcedureHeading ";" =: |
| |
| AsmStatement := 'ASM' [ 'VOLATILE' ] '(' AsmOperands ')' =: |
| |
| NamedOperand := '[' Ident ']' =: |
| |
| AsmOperandName := [ NamedOperand ] =: |
| |
| AsmOperands := ConstExpression [ ':' AsmList [ ':' AsmList [ ':' TrashList ] ] ] |
| =: |
| |
| AsmList := [ AsmElement ] { ',' AsmElement } =: |
| |
| AsmElement := AsmOperandName ConstExpression '(' Expression ')' |
| =: |
| |
| TrashList := [ ConstExpression ] { ',' ConstExpression } =: |
| |
| FNB |
