cppparser
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Published
20 hours ago •
satya-das
satya-das
Grammar railroad diagram
After extend btyacc (see diff bellow) to output an EBNF understood by https://www.bottlecaps.de/rr/ui and manually add the tokens from parser.l we can have a nice navigable railroad diagram.
Copy and paste the EBNF shown bellow on https://www.bottlecaps.de/rr/ui on the tab Edit Grammar the click on the tab View Diagram to see/download a navigable railroad diagram.
//EBNF to create railroad diagram
progunit ::= optstmtlist
optstmtlist ::=
| stmtlist
stmtlist ::= stmt
| stmtlist stmt
| optstmtlist changeprotlevel
stmt ::= vardeclstmt
| vardeclliststmt
| enumdefnstmt
| enumfwddecl
| typedefnamestmt
| typedefliststmt
| classdefnstmt
| namespacedefn
| fwddecl
| doccomment
| exprstmt
| ifblock
| whileblock
| dowhileblock
| forblock
| forrangeblock
| funcpointerdecl
| funcdeclstmt
| funcdefn
| ctordeclstmt
| ctordefn
| dtordeclstmt
| dtordefn
| typeconverterstmt
| externcblock
| funcptrtypedef
| preprocessor
| block
| switchstmt
| tryblock
| usingdecl
| usingnamespacedecl
| namespacealias
| macrocall
| macrocall ';'
| apidecortokensq macrocall
| ';'
| asmblock
| blob
| label
label ::= name ':'
preprocessor ::= define
| undef
| include
| import
| hashif
| hasherror
| hashwarning
| pragma
asmblock ::= tknAsm
macrocall ::= tknMacro
macrocall ::= macrocall '(' ')'
macrocall ::= macrocall '(' expr ')'
switchstmt ::= tknSwitch '(' expr ')' '{' caselist '}'
caselist ::=
| caselist tknCase expr ':' optstmtlist
| caselist tknDefault ':' optstmtlist
| doccommentstr caselist
| caselist doccommentstr
block ::= '{' optstmtlist '}'
| doccomment block
ifblock ::= tknIf '(' expr ')' stmt
| tknIf '(' varinit ')' stmt
| ifblock tknElse stmt
whileblock ::= tknWhile '(' expr ')' stmt
| tknWhile '(' varinit ')' stmt
dowhileblock ::= tknDo stmt tknWhile '(' expr ')'
forblock ::= tknFor '(' optexpr ';' optexpr ';' optexpr ')' stmt
| tknFor '(' varinit ';' optexpr ';' optexpr ')' stmt
| tknFor '(' vardecllist ';' optexpr ';' optexpr ')' stmt
forrangeblock ::= tknFor '(' vardecl ':' expr ')' stmt
tryblock ::= tknTry block catchblock
| tryblock catchblock
catchblock ::= tknCatch '(' vartype optname ')' block
optexpr ::=
| expr
| exprlist
define ::= tknPreProHash tknDefine name name
| tknPreProHash tknDefine name
| tknPreProHash tknDefine name tknNumber
| tknPreProHash tknDefine name tknStrLit
| tknPreProHash tknDefine name tknCharLit
| tknPreProHash tknDefine name tknPreProDef
undef ::= tknPreProHash tknUndef name
include ::= tknPreProHash tknInclude tknStrLit
| tknPreProHash tknInclude tknStdHdrInclude
import ::= tknPreProHash tknImport tknStrLit
| tknPreProHash tknImport tknStdHdrInclude
hashif ::= tknPreProHash tknIf tknPreProDef
| tknPreProHash tknIfDef name
| tknPreProHash tknIfNDef name
| tknPreProHash tknIfNDef tknApiDecor
| tknPreProHash tknElse
| tknPreProHash tknElIf tknPreProDef
| tknPreProHash tknEndIf
hasherror ::= tknPreProHash tknHashError
| tknPreProHash tknHashError strlit
hashwarning ::= tknPreProHash tknHashWarning
| tknPreProHash tknHashWarning strlit
pragma ::= tknPreProHash tknPragma tknPreProDef
doccomment ::= doccommentstr
doccommentstr ::= tknFreeStandingBlockComment
| tknFreeStandingLineComment
| doccommentstr tknFreeStandingBlockComment
| doccommentstr tknFreeStandingLineComment
identifier ::= name
identifier ::= identifier tknScopeResOp identifier
identifier ::= id
identifier ::= templidentifier
identifier ::= tknOverride
identifier ::= identifier tknEllipsis
identifier ::= macrocall
identifier ::= templqualifiedid
numbertype ::= tknInteger
| tknFloat
| tknDouble
| tknChar
| tknNumSignSpec
| tknNumSignSpec numbertype
typeidentifier ::= identifier
| tknScopeResOp identifier
| typeidentifier tknScopeResOp typeidentifier
| numbertype
| tknAuto
| tknVoid
| tknEnum identifier
| tknTypename identifier
| tknEllipsis
| tknTypename tknEllipsis
| tknClass tknEllipsis
| typeidentifier tknEllipsis
| tknDecltype '(' expr ')'
templidentifier ::= identifier tknLT templatearglist tknGT
templidentifier ::= identifier tknLT expr tknNotEq expr tknGT
templidentifier ::= identifier tknLT templatearglist ',' expr tknNotEq expr tknGT
templqualifiedid ::= tknTemplate templidentifier
name ::= tknName
id ::= tknID
optname ::=
| name
optidentifier ::=
| identifier
enumitem ::= name
| name '=' expr
| doccomment
| preprocessor
| macrocall
| blob
blob ::= tknBlob
enumitemlist ::=
| enumitemlist enumitem
| enumitemlist ',' enumitem
| enumitemlist ','
enumdefn ::= tknEnum optname '{' enumitemlist '}'
| tknEnum optapidecor name ':' typeidentifier '{' enumitemlist '}'
| tknEnum ':' typeidentifier '{' enumitemlist '}'
| tknEnum optapidecor name '{' enumitemlist '}'
| tknEnum tknClass optapidecor name ':' typeidentifier '{' enumitemlist '}'
| tknEnum tknClass optapidecor name '{' enumitemlist '}'
| tknTypedef tknEnum optapidecor optname '{' enumitemlist '}' name
enumdefnstmt ::= enumdefn ';'
enumfwddecl ::= tknEnum name ':' typeidentifier ';'
| tknEnum tknClass name ':' typeidentifier ';'
| tknEnum tknClass name ';'
funcptrtypedef ::= tknTypedef functionpointer ';'
typedefnamestmt ::= typedefname ';'
typedefliststmt ::= typedeflist ';'
typedeflist ::= tknTypedef vardecllist
typedefname ::= tknTypedef vardecl
usingdecl ::= tknUsing name '=' vartype ';'
| tknUsing name '=' functionptrtype ';'
| tknUsing name '=' funcobj ';'
| tknUsing name '=' classdefn ';'
| templatespecifier usingdecl
| tknUsing identifier ';'
namespacealias ::= tknNamespace name '=' identifier ';'
usingnamespacedecl ::= tknUsing tknNamespace identifier ';'
vardeclliststmt ::= vardecllist ';'
| exptype vardecllist ';'
vardeclstmt ::= vardecl ';'
| varinit ';'
| apidecor vardeclstmt
| exptype vardeclstmt
| varattrib vardeclstmt
vardecllist ::= optfunctype varinit ',' opttypemodifier name optvarassign
| optfunctype vardecl ',' opttypemodifier name optvarassign
| optfunctype vardecl ',' opttypemodifier name '[' expr ']'
| optfunctype vardecl ',' opttypemodifier name ':' expr
| vardecllist ',' opttypemodifier name optvarassign
| vardecllist ',' opttypemodifier name optvarassign ':' expr
varinit ::= vardecl '(' typeidentifier '*' name
| vardecl '(' typeidentifier '*' '*' name
| vardecl '(' typeidentifier '*' '&' name
| vardecl '(' typeidentifier '&' name
| vardecl '(' typeidentifier tknAnd name
| vardecl '(' typeidentifier ')'
| vardecl '(' ')'
| vardecl varassign
| tknConstExpr varinit
varassign ::= '=' expr
| '(' exprorlist ')'
| '{' funcargs '}'
optvarassign ::=
| varassign
vardecl ::= vartype varidentifier
| vartype apidecor varidentifier
| functionpointer
| vardecl '[' expr ']'
| vardecl '[' ']'
| vardecl ':' expr
| templatespecifier vardecl
| varattrib vardecl
vartype ::= attribspecifiers typeidentifier opttypemodifier
| typeidentifier opttypemodifier
| tknClass identifier opttypemodifier
| tknClass optapidecor identifier opttypemodifier
| tknStruct optapidecor identifier opttypemodifier
| tknUnion identifier opttypemodifier
| functionptrtype
| classdefn
| classdefn typemodifier
| enumdefn
| enumdefn typemodifier
| varattrib vartype
| vartype tknEllipsis
| typeidentifier typeidentifier tknScopeResOp typemodifier
varidentifier ::= identifier
| tknFinal
| '(' '&' name ')'
| '(' '*' name ')'
| '(' '*' '*' name ')'
opttypemodifier ::=
| typemodifier
| doccomment opttypemodifier
typemodifier ::= tknConst
| '*'
| '&'
| tknAnd
| typemodifier tknConst
| typemodifier '*'
| typemodifier '&'
| typemodifier tknAnd
exptype ::= tknStatic
| tknExtern
| tknExternC
varattrib ::= tknConst
| tknVolatile
| tknMutable
| tknConstExpr
typeconverter ::= tknOperator vartype '(' optvoid ')'
| identifier tknScopeResOp tknOperator vartype '(' optvoid ')'
| functype typeconverter
| typeconverter tknConst
| apidecor typeconverter
| templatespecifier typeconverter
typeconverterstmt ::= typeconverter ';'
| typeconverter block
funcdeclstmt ::= funcdecl ';'
funcdefn ::= funcdecl block
lambda ::= '[' lambdacapture ']' lambdaparams block
| '[' lambdacapture ']' lambdaparams tknArrow vartype block
lambdaparams ::=
| '(' paramlist ')'
funcptrortype ::= functype vartype '(' optapidecor identifier tknScopeResOp '*' optname ')' '(' paramlist ')'
| vartype '(' optapidecor identifier tknScopeResOp '*' optname ')' '(' paramlist ')'
| functype vartype '(' optapidecor '*' optname ')' '(' paramlist ')'
| vartype '(' optapidecor '*' optname ')' '(' paramlist ')'
| vartype '(' '*' apidecor optname ')' '(' paramlist ')'
| apidecor funcptrortype
| funcptrortype optfuncattrib
functionpointer ::= funcptrortype
functionptrtype ::= funcptrortype
funcobj ::= vartype optapidecor '(' paramlist ')'
funcpointerdecl ::= functionpointer ';'
funcdecldata ::= funcname '(' paramlist ')'
| funcname '(' paramlist ')' optfuncattrib
funcdecl ::= vartype apidecor funcdecldata
| vartype funcdecldata
| vartype tknConstExpr funcdecldata
| tknAuto funcdecldata tknArrow vartype
| tknAuto tknConstExpr funcdecldata tknArrow vartype
| tknConstExpr funcdecl
| apidecor funcdecl
| templatespecifier funcdecl
| functype funcdecl
| funcdecl '=' tknDelete
| funcdecl '=' tknDefault
| funcdecl functhrowspec
funcobjstr ::= typeidentifier optapidecor '(' paramlist ')'
funcname ::= operfuncname
| typeidentifier
| tknScopeResOp operfuncname
| tknFinal
rshift ::= tknGT tknGT
operfuncname ::= tknOperator '+'
| tknOperator '-'
| tknOperator '*'
| tknOperator '/'
| tknOperator '%'
| tknOperator '^'
| tknOperator '&'
| tknOperator '|'
| tknOperator '~'
| tknOperator '!'
| tknOperator '='
| tknOperator tknLT
| tknOperator tknGT
| tknOperator tknPlusEq
| tknOperator tknMinusEq
| tknOperator tknMulEq
| tknOperator tknDivEq
| tknOperator tknPerEq
| tknOperator tknXorEq
| tknOperator tknAndEq
| tknOperator tknOrEq
| tknOperator tknLShift
| tknOperator tknRShift
| tknOperator tknLShiftEq
| tknOperator tknRShiftEq
| tknOperator tknCmpEq
| tknOperator tknNotEq
| tknOperator tknLessEq
| tknOperator tknGreaterEq
| tknOperator tkn3WayCmp
| tknOperator tknAnd
| tknOperator tknOr
| tknOperator tknInc
| tknOperator tknDec
| tknOperator ','
| tknOperator tknArrow
| tknOperator tknArrowStar
| tknOperator '(' ')'
| tknOperator '[' ']'
| tknOperator tknNew
| tknOperator tknNew '[' ']'
| tknOperator tknDelete
| tknOperator tknDelete '[' ']'
| tknOperator typeidentifier
| tknOperator typeidentifier '*'
| identifier tknScopeResOp operfuncname
| tknOperator tknStrLit name
| operfuncname tknLT templatearglist tknGT
paramlist ::=
| param
| paramlist ',' param
param ::= varinit
| vartype '=' expr
| vardecl
| vartype
| funcptrortype
| doccomment param
| vartype '[' expr ']'
| vartype '[' ']'
templatearg ::=
templatearg ::= vartype
templatearg ::= funcobjstr
templatearg ::= expr
templatearglist ::= templatearg
templatearglist ::= templatearglist ',' templatearg
templatearglist ::= templatearglist ',' doccomment templatearg
functype ::= exptype
| tknInline
| tknVirtual
| tknExplicit
| tknFriend
| tknConstExpr
optfunctype ::=
| functype
optfuncattrib ::= tknConst
| tknOverride
| tknFinal
| tknNoExcept
| '=' tknNumber
| optfuncattrib tknConst
| optfuncattrib tknOverride
| optfuncattrib tknFinal
| optfuncattrib tknNoExcept
| optfuncattrib '=' tknNumber
| tknMacro
optfuncthrowspec ::=
| functhrowspec
functhrowspec ::= tknThrow '(' identifierlist ')'
identifierlist ::=
| identifier
| identifierlist ',' identifier
ctordeclstmt ::= ctordecl ';'
ctordefn ::= ctordecl meminitlist block
ctordefn ::= name tknScopeResOp name '(' paramlist ')' optfuncthrowspec meminitlist block
ctordefn ::= identifier tknScopeResOp name tknScopeResOp name '(' paramlist ')' optfuncthrowspec meminitlist block
ctordefn ::= name tknLT templatearglist tknGT tknScopeResOp name '(' paramlist ')' optfuncthrowspec meminitlist block
| functype ctordefn
| templatespecifier ctordefn
ctordecl ::= identifier '(' paramlist ')'
| functype ctordecl
| templatespecifier ctordecl
| ctordecl '=' tknDelete
| ctordecl '=' tknDefault
| ctordecl functhrowspec
| ctordecl tknNoExcept
| apidecor ctordecl
meminitlist ::=
| ':' meminit
| ':' blob
| meminitlist ',' meminit
meminit ::= identifier '(' exprorlist ')'
| identifier '(' ')'
| identifier '{' exprorlist '}'
| identifier '{' '}'
dtordeclstmt ::= dtordecl ';'
dtordefn ::= dtordecl block
dtordefn ::= name tknScopeResOp '~' name '(' ')' block
dtordefn ::= identifier tknScopeResOp name tknScopeResOp '~' name '(' ')' block
dtordefn ::= name tknLT templatearglist tknGT tknScopeResOp '~' name '(' ')' block
| templatespecifier dtordefn
| functype dtordefn
dtordecl ::= '~' name '(' optvoid ')'
| apidecor dtordecl
| functype dtordecl
| dtordecl optfuncattrib
| dtordecl '=' tknNumber
| dtordecl '=' tknDelete
| dtordecl '=' tknDefault
| dtordecl functhrowspec
optvoid ::=
| tknVoid
optcomment ::=
| doccomment
classdefnstmt ::= classdefn ';'
attribspecifier ::= '[' '[' expr ']' ']'
optattribspecifiers ::=
| attribspecifiers
attribspecifiers ::= attribspecifier
| attribspecifiers attribspecifier
classdefn ::= classspecifier optapidecor optattribspecifiers identifier optfinal optinheritlist optcomment '{' optstmtlist '}'
classdefn ::= classspecifier optattribspecifiers optinheritlist optcomment '{' optstmtlist '}'
| templatespecifier classdefn
namespacedefn ::= tknNamespace optidentifier '{' optstmtlist '}'
optfinal ::=
| tknFinal
optinheritlist ::=
| ':' protlevel optinherittype typeidentifier
| optinheritlist ',' protlevel optinherittype typeidentifier
| ':' optinherittype protlevel typeidentifier
| optinheritlist ',' optinherittype protlevel typeidentifier
protlevel ::=
| tknPublic
| tknProtected
| tknPrivate
optinherittype ::=
| tknVirtual
fwddecl ::= classspecifier typeidentifier ';'
| classspecifier optapidecor identifier ';'
| templatespecifier fwddecl
| tknFriend typeidentifier ';'
| tknFriend fwddecl
classspecifier ::= tknClass
| tknStruct
| tknUnion
templatespecifier ::= tknTemplate tknLT templateparamlist tknGT
templateparamlist ::=
| templateparam
| templateparamlist ',' templateparam
templateparam ::= tknTypename optname
| tknTypename optname '=' vartype
| tknClass optname
| tknClass optname '=' vartype
| vartype name
| vartype name '=' expr
| functionpointer
| functionpointer '=' expr
| vartype
| vartype '=' expr
| tknTypename name ','
| tknTypename name '='
| tknTypename name tknGT
| tknClass name ','
| tknClass name tknGT
optapidecor ::=
| apidecor
apidecor ::= apidecortokensq
| apidecortokensq '(' name ')'
| apidecortokensq '(' tknNumber ')'
| apidecortokensq '(' strlit ')'
apidecortokensq ::= tknApiDecor
| apidecortokensq tknApiDecor
| tknApiDecor '(' strlit ')'
changeprotlevel ::= tknPublic ':'
| tknProtected ':'
| tknPrivate ':'
externcblock ::= tknExternC block
strlit ::= tknStrLit
| strlit tknStrLit
expr ::= strlit
| tknCharLit
| tknNumber
| '+' tknNumber
| identifier
| '{' exprlist '}'
| '{' exprlist ',' '}'
| '{' exprorlist '}'
| '{' exprorlist ',' '}'
| '{' '}'
| '-' expr
| '~' expr
| '!' expr
| '*' expr
| '&' expr
| '&' operfuncname
| tknInc expr
| expr tknInc
| tknDec expr
| expr tknDec
| expr '+' expr
| expr '-' expr
| expr '*' expr
| expr '/' expr
| expr '%' expr
| expr '&' expr
| expr '|' expr
| expr '^' expr
| expr '=' expr
| expr tknLT expr
| expr tknGT expr
| expr '?' expr ':' expr
| expr tknPlusEq expr
| expr tknMinusEq expr
| expr tknMulEq expr
| expr tknDivEq expr
| expr tknPerEq expr
| expr tknXorEq expr
| expr tknAndEq expr
| expr tknOrEq expr
| expr tknLShift expr
| expr rshift expr
| expr tknLShiftEq expr
| expr tknRShiftEq expr
| expr tknCmpEq expr
| expr tknNotEq expr
| expr tknLessEq expr
| expr tknGreaterEq expr
| expr tkn3WayCmp expr
| expr tknAnd expr
| expr tknOr expr
| expr '.' funcname
| expr '.' '*' funcname
| expr tknArrow funcname
| expr tknArrowStar funcname
| expr '.' '~' funcname
| expr tknArrow '~' funcname
| expr '[' expr ']'
| expr '[' ']'
| expr '(' funcargs ')'
| funcname '(' funcargs ')'
| expr tknArrow '~' identifier '(' ')'
| identifier '{' funcargs '}'
| '(' vartype ')' expr
| tknConstCast tknLT vartype tknGT '(' expr ')'
| tknStaticCast tknLT vartype tknGT '(' expr ')'
| tknDynamicCast tknLT vartype tknGT '(' expr ')'
| tknReinterpretCast tknLT vartype tknGT '(' expr ')'
| '(' exprorlist ')'
| tknNew typeidentifier opttypemodifier
| tknNew expr
| tknNew '(' expr ')' expr
| tknScopeResOp tknNew '(' expr ')' expr
| tknDelete expr
| tknDelete '[' ']' expr
| tknReturn exprorlist
| tknReturn
| tknThrow expr
| tknThrow
| tknSizeOf '(' vartype ')'
| tknSizeOf '(' expr ')'
| tknSizeOf tknEllipsis '(' vartype ')'
| tknSizeOf tknEllipsis '(' expr ')'
| expr tknEllipsis
| lambda
| tknGoto name
| tknNumber name
| '[' expr expr ']'
| '[' expr objcarglist ']'
objcarg ::= name ':' expr
objcarglist ::= objcarg
| objcarglist objcarg
exprlist ::= expr ',' expr
| exprlist ',' expr
| doccommentstr exprlist
exprorlist ::= expr
| exprlist
| doccommentstr exprorlist
funcargs ::=
| exprorlist
captureallbyref ::= '&'
captureallbyval ::= '='
lambdacapture ::= funcargs
| captureallbyref
| captureallbyval
exprstmt ::= expr ';'
// Tokens
tknScopeResOp ::= "::"
tknConst ::= "const"
tknConstExpr ::= "constexpr"
tknStatic ::= "static"
tknInline ::= "inline"
tknVirtual ::= "virtual"
tknOverride ::= "override"
tknFinal ::= "final"
tknNoExcept ::= "noexcept"
tknExtern ::= "extern"
tknExplicit ::= "explicit"
tknFriend ::= "friend"
tknExternC ::= "extern" '"C"'
tknVolatile ::= "volatile"
tknMutable ::= "mutable"
tknNew ::= "new"
tknDelete ::= "delete"
tknDefault ::= "default"
tknReturn ::= "return"
tknIf ::= "if"
tknElse ::= "else"
tknFor ::= "for"
tknDo ::= "do"
tknWhile ::= "while"
tknSwitch ::= "switch"
tknCase ::= "case"
tknConstCast ::= "const_cast"
tknStaticCast ::= "static_cast"
tknDynamicCast ::= "dynamic_cast"
tknReinterpretCast ::= "reinterpret_cast"
tknTry ::= "try"
tknCatch ::= "catch"
tknThrow ::= "throw"
tknSizeOf ::= "sizeof"
tknOperator ::= "operator"
tknVoid ::= "void"
tknPlusEq ::= "+="
tknMinusEq ::= "-="
tknMulEq ::= "*="
tknDivEq ::= "/="
tknPerEq ::= "%="
tknXorEq ::= "^="
tknAndEq ::= "&="
tknOrEq ::= "|="
tknLShift ::= "<<"
tknLShiftEq ::= "<<="
tknLT ::= "<"
tknRShift ::= ">>"
tknGT ::= ">"
tknRShiftEq ::= ">>="
tknCmpEq ::= "=="
tknNotEq ::= "!="
tknLessEq ::= "<="
tknGreaterEq ::= ">="
tkn3WayCmp ::= "<=>"
tknAnd ::= "&&"
tknOr ::= "||"
tknInc ::= "++"
tknDec ::= "--"
tknArrow ::= "->"
tknArrowStar ::= "->*"
tknAsm ::= "asm"
tknGoto ::= "goto"
tknNumSignSpec ::= "signed" | "unsigned"
tknInteger ::= "long" "long" "int" | "long" "long" | "long" "int" | "long" | "int" | "short" "int"| "short"
tknInteger ::= "__int8" | "__int16" | "__int32" | "__int64" | "__int128"
tknChar ::= "char"
tknDouble ::= "long" "double" | "double"
tknFloat ::= "long" "float" | "float"
tknAuto ::= "auto"
tknTypedef ::= "typedef"
tknUsing ::= using
tknClass ::= "class"
tknNamespace ::= "namespace"
tknStruct ::= "struct"
tknUnion ::= "union"
tknEnum ::= "enum" ("class"? ID? (":"* ID)? "{")?
tknPublic ::= "public" ":"?
tknProtected ::= "protected"":"?
tknPrivate ::= "private" ":"?
tknTemplate ::= "template"
tknTypename ::= "typename"
tknDecltype ::= "decltype"
tknPreProHash ::= '#'
tknDefine ::= "define"
tknUndef ::= "undef"
tknInclude ::= "include"
tknHashErrror ::= "error"
tknPragma ::= "pragma"
tknImport ::= "import"
tknElif ::= "elif"
tknIfdef ::= "ifdef"
tknIfndef ::= "ifndef"
tknEndif ::= "endif"
tknHashWarning ::= "warning"
Patch to add EBNF output to btyacc:
diff --git a/third_party/btyacc_tp/btyacc/defs.h b/third_party/btyacc_tp/btyacc/defs.h
index 2b738773..9009e6ae 100644
--- a/third_party/btyacc_tp/btyacc/defs.h
+++ b/third_party/btyacc_tp/btyacc/defs.h
@@ -69,6 +69,7 @@ typedef int Yshort;
#define CODE_SUFFIX ".code.c"
#endif /* MSDOS */
#define VERBOSE_SUFFIX ".output"
+#define EBNF_SUFFIX ".ebnf"
/* keyword codes */
@@ -254,6 +255,7 @@ extern char rflag;
extern char tflag;
extern char vflag;
extern char include_defines;
+extern char ebnfflag;
extern char *myname;
extern char *symbol_prefix;
@@ -278,6 +280,7 @@ extern FILE *output_file;
extern FILE *text_file;
extern FILE *union_file;
extern FILE *verbose_file;
+extern FILE *ebnf_file;
extern int nitems;
extern int nrules;
@@ -534,6 +537,7 @@ void check_symbols(void);
void pack_symbols(void);
void pack_grammar(void);
void print_grammar(void);
+void print_grammar_ebnf(void);
void reader(void);
/* readskel.c */
diff --git a/third_party/btyacc_tp/btyacc/main.c b/third_party/btyacc_tp/btyacc/main.c
index 7ab280b4..9062fecd 100644
--- a/third_party/btyacc_tp/btyacc/main.c
+++ b/third_party/btyacc_tp/btyacc/main.c
@@ -8,6 +8,7 @@ char lflag;
char rflag;
char tflag;
char vflag;
+char ebnfflag;
int Eflag = 0;
char *symbol_prefix = "yy";
@@ -33,6 +34,7 @@ char *output_file_name;
char *text_file_name;
char *union_file_name;
char *verbose_file_name;
+char *ebnf_file_name;
FILE *action_file; /* a temp file, used to save actions associated */
/* with rules until the parser is written */
@@ -45,6 +47,7 @@ FILE *union_file; /* a temp file, used to save the union */
/* definition until all symbol have been */
/* defined */
FILE *verbose_file; /* y.output */
+FILE *ebnf_file; /* y.ebnf */
int nitems;
int nrules;
@@ -101,7 +104,7 @@ void set_signals()
void usage()
{
- fprintf(stderr, "usage: %s [-dlrtv] [-b file_prefix] [-S skeleton file] "
+ fprintf(stderr, "usage: %s [-delrtv] [-b file_prefix] [-S skeleton file] "
"[-p symbol_prefix] filename\n", myname);
exit(1);
}
@@ -167,6 +170,10 @@ void getargs(int argc, char **argv)
}
continue;
+ case 'e':
+ ebnfflag = 1;
+ break;
+
case 'E':
Eflag = 1;
break;
@@ -215,6 +222,10 @@ void getargs(int argc, char **argv)
dflag = 1;
break;
+ case 'e':
+ ebnfflag = 1;
+ break;
+
case 'l':
lflag = 1;
break;
@@ -375,6 +386,15 @@ void create_file_names()
strcpy(defines_file_name + len, DEFINES_SUFFIX);
}
+ if (ebnfflag)
+ {
+ ebnf_file_name = MALLOC(len + 8);
+ if (ebnf_file_name == 0)
+ no_space();
+ strcpy(ebnf_file_name, file_prefix);
+ strcpy(ebnf_file_name + len, EBNF_SUFFIX);
+ }
+
if (vflag)
{
verbose_file_name = MALLOC(len + 8);
@@ -405,6 +425,13 @@ void open_files()
open_error(verbose_file_name);
}
+ if (ebnfflag)
+ {
+ ebnf_file = fopen(ebnf_file_name, "w");
+ if (ebnf_file == 0)
+ open_error(ebnf_file_name);
+ }
+
if (dflag)
{
defines_file = fopen(defines_file_name, "w");
diff --git a/third_party/btyacc_tp/btyacc/reader.c b/third_party/btyacc_tp/btyacc/reader.c
index b87a617b..71c4750d 100644
--- a/third_party/btyacc_tp/btyacc/reader.c
+++ b/third_party/btyacc_tp/btyacc/reader.c
@@ -2010,6 +2010,39 @@ void print_grammar()
putc('\n', f); }
}
+void print_grammar_ebnf()
+{
+ register int i, j, k, skip_rule;
+ int spacing = 0;
+ register FILE *f = ebnf_file;
+ const char *name;
+
+ if (!ebnfflag) return;
+
+ fprintf(f, "\n//EBNF to create railroad diagram\n");
+
+ k = 1;
+ for (i = 2; i < nrules; ++i) {
+ name = symbol_name[rlhs[i]];
+ skip_rule = name[0] == '$';
+ if(!skip_rule) {
+ if (rlhs[i] != rlhs[i-1]) {
+ if (i != 2) fprintf(f, "\n");
+ fprintf(f, "%s ::=", name);
+ spacing = strlen(name) + 1; }
+ else {
+ j = spacing;
+ while (--j >= 0) putc(' ', f);
+ putc('|', f); }
+ }
+ while (ritem[k] >= 0) {
+ if(!skip_rule && symbol_name[ritem[k]][0] != '$') fprintf(f, " %s", symbol_name[ritem[k]]);
+ ++k; }
+ ++k;
+ putc('\n', f); }
+ fputs("\n", f);
+}
+
extern int read_errs;
void reader() {
@@ -2027,5 +2060,6 @@ void reader() {
free_tags();
pack_grammar();
free_symbols();
+ print_grammar_ebnf();
print_grammar();
}
Sorry that I didn't get a chance to look at it before. This is indeed very nice. I will suggest to open a PR for https://github.com/ChrisDodd/btyacc with the changes mentioned here.
cppparser is now using latest btyacc that has this change already. Closing this issue.