Wrong links for stateToString in internal doxygen documentation

When looking at the code of e.g. scanner.l in the doxygen internal documentation and looking at the prototype of the function `stateToString` this function is linked to the same function in the fortranscanner (although this should no happen as the function is `static`).
Due to the fact that the `stateToString` functionality is only enabled in the fortranscanner, but in the other lex scanners the prototype and the implementation is hidden inside a `#if` block but the (lex)code scanners still find it as it does not take the `#if` into account.
- enable the functionality of `stateToString` everywhere even when not used
- make the prototypes `[[maybe_unused]]` to satisfy the compilers (warnings)
- adjust `pre.l` so that the counting of the open / close brackets is correct when they are used in the rules (code taken from lexscanner.l)
- some minor fixes to keep the preprocessor happy  (commands in regular comments, escape double quotes in `[...]` part of the rules

Author: albert-github

src/code.l

@@ -78,8 +78,6 @@ typedef yyguts_t *yyscan_t;
 #define SCOPEBLOCK 2
 #define INNERBLOCK 3
 
-#define USE_STATE2STRING 0
-
 // context for an Objective-C method call
 struct ObjCCallCtx
 {
@@ -197,9 +195,7 @@ struct codeYY_state
 static bool isCastKeyword(const char *s);
 
 //-------------------------------------------------------------------
-#if USE_STATE2STRING
-static const char *stateToString(int state);
-#endif
+[[maybe_unused]] static const char *stateToString(int state);
 
 static void saveObjCContext(yyscan_t yyscanner);
 static void restoreObjCContext(yyscan_t yyscanner);
@@ -4202,6 +4198,4 @@ void CCodeParser::parseCode(OutputCodeList &od,const QCString &className,const Q
   yyextra->tooltipManager.writeTooltips(od);
 }
 
-#if USE_STATE2STRING
 #include "code.l.h"
-#endif

src/commentcnv.l

@@ -49,8 +49,6 @@ typedef yyguts_t *yyscan_t;
 #define ADDCHAR(c)    yyextra->outBuf.addChar(c)
 #define ADDARRAY(a,s) yyextra->outBuf.addArray(a,s)
 
-#define USE_STATE2STRING 0
-
 struct commentcnvYY_CondCtx
 {
   commentcnvYY_CondCtx(int line,const QCString &id,bool b)
@@ -105,9 +103,7 @@ struct commentcnvYY_state
   bool       isFixedForm = FALSE; // For Fortran
 };
 
-#if USE_STATE2STRING
-static const char *stateToString(int state);
-#endif
+[[maybe_unused]] static const char *stateToString(int state);
 static inline int computeIndent(const char *s);
 
 static void replaceCommentMarker(yyscan_t yyscanner,const char *s,int len);
@@ -1290,6 +1286,4 @@ void convertCppComments(const BufStr &inBuf,BufStr &outBuf,const QCString &fileN
 
 //----------------------------------------------------------------------------
 
-#if USE_STATE2STRING
 #include "commentcnv.l.h"
-#endif

src/commentscan.l

@@ -64,8 +64,6 @@ typedef yyguts_t *yyscan_t;
 #include "trace.h"
 #include "debug.h"
 
-#define USE_STATE2STRING 0
-
 // forward declarations
 static bool handleBrief(yyscan_t yyscanner,const QCString &, const StringVector &);
 static bool handleFn(yyscan_t yyscanner,const QCString &, const StringVector &);
@@ -166,9 +164,7 @@ static bool handleFileInfo(yyscan_t yyscanner,const QCString &, const StringVect
 static bool handleLineInfo(yyscan_t yyscanner,const QCString &, const StringVector &);
 static bool handleModule(yyscan_t yyscanner,const QCString &, const StringVector &);
 
-#if USE_STATE2STRING
-static const char *stateToString(int state);
-#endif
+[[maybe_unused]] static const char *stateToString(int state);
 
 typedef bool (*DocCmdFunc)(yyscan_t yyscanner,const QCString &name, const StringVector &optList);
 
@@ -831,7 +827,7 @@ STopt  [^\n@\\]*
                                           // the {B}* in the front was added for bug620924
                                           QCString fullMatch = QCString(yytext);
                                           int idx = fullMatch.find('{');
-                                          /* handle `\f{` and `@f{` as special cases */
+                                          /* handle `f{` command as special case */
                                           if ((idx > 1) && (yytext[idx-1] == 'f') && (yytext[idx-2] == '\\' || yytext[idx-2] =='@')) REJECT;
                                           int idxEnd = fullMatch.find("}",idx+1);
                                           QCString cmdName;
@@ -4217,6 +4213,4 @@ void CommentScanner::close(Entry *e,const QCString &fileName,int lineNr,bool fou
   yyextra->docGroup.close(e,fileName,lineNr,foundInline,implicit);
 }
 
-#if USE_STATE2STRING
 #include "commentscan.l.h"
-#endif

src/configimpl.l

@@ -52,11 +52,7 @@
 // For debugging
 #define SHOW_INCLUDES 0
 
-#define USE_STATE2STRING 0
-
-#if USE_STATE2STRING
-static const char *stateToString(int state);
-#endif
+[[maybe_unused]] static const char *stateToString(int state);
 
 static const char *warning_str = "warning: ";
 static const char *error_str = "error: ";
@@ -2323,6 +2319,4 @@ void Config::deinit()
   ConfigImpl::instance()->deleteInstance();
 }
 
-#if USE_STATE2STRING
 #include "configimpl.l.h"
-#endif

src/constexp.l

@@ -37,11 +37,7 @@
 #define YY_NO_INPUT 1
 #define YY_NO_UNISTD_H 1
 
-#define USE_STATE2STRING 0
-
-#if USE_STATE2STRING
-static const char *stateToString(int state);
-#endif
+[[maybe_unused]] static const char *stateToString(int state);
 
 static int yyread(char *buf,int max_size,yyscan_t yyscanner);
 
@@ -170,6 +166,4 @@ extern "C" {
   int constexpYYwrap(yyscan_t /* yyscanner */) { return 1; }
 }
 
-#if USE_STATE2STRING
 #include "constexp.l.h"
-#endif

src/declinfo.l

@@ -48,8 +48,6 @@ typedef yyguts_t *yyscan_t;
 #define YY_NO_UNISTD_H 1
 #define YY_NEVER_INTERACTIVE 1
 
-#define USE_STATE2STRING 0
-
 /* -----------------------------------------------------------------
  *
  *	statics
@@ -74,9 +72,7 @@ struct declinfoYY_state
      bool         insidePHP;
 };
 
-#if USE_STATE2STRING
-static const char *stateToString(int state);
-#endif
+[[maybe_unused]] static const char *stateToString(int state);
 
 static void addType(yyscan_t yyscanner);
 static void addTypeName(yyscan_t yyscanner);
@@ -419,6 +415,4 @@ int main()
 }
 #endif
 
-#if USE_STATE2STRING
 #include "declinfo.l.h"
-#endif

src/defargs.l

@@ -71,8 +71,6 @@ typedef yyguts_t *yyscan_t;
 #define YY_NO_INPUT 1
 #define YY_NO_UNISTD_H 1
 
-#define USE_STATE2STRING 0
-  
 /* -----------------------------------------------------------------
  *	state variables
  */
@@ -104,9 +102,7 @@ struct defargsYY_state
   QCString         delimiter;
 };
 
-#if USE_STATE2STRING
-static const char *stateToString(int state);
-#endif
+[[maybe_unused]] static const char *stateToString(int state);
 
 static int yyread(yyscan_t yyscanner,char *buf,int max_size);
 static bool nameIsActuallyPartOfType(QCString &name);
@@ -841,6 +837,4 @@ std::unique_ptr<ArgumentList> stringToArgumentList(SrcLangExt lang, const QCStri
   return al;
 }
 
-#if USE_STATE2STRING
 #include "defargs.l.h"
-#endif

src/doctokenizer.l

@@ -51,8 +51,6 @@ typedef yyguts_t *yyscan_t;
 #define YY_NO_INPUT 1
 #define YY_NO_UNISTD_H 1
 
-#define USE_STATE2STRING 0
-
 #define TK_COMMAND_SEL() (yytext[0] == '@' ? TK_COMMAND_AT : TK_COMMAND_BS)
 
 //--------------------------------------------------------------------------
@@ -98,10 +96,7 @@ struct doctokenizerYY_state
 #define lineCount(s,len) do { for(int i=0;i<(int)len;i++) if (s[i]=='\n') yyextra->yyLineNr++; } while(0)
 
 
-#if USE_STATE2STRING
-static const char *stateToString(int state);
-#endif
-
+[[maybe_unused]] static const char *stateToString(int state);
 
 static int yyread(yyscan_t yyscanner,char *buf,int max_size);
 static void handleHtmlTag(yyscan_t yyscanner,const char *text);
@@ -2183,6 +2178,4 @@ int DocTokenizer::getLineNr(void)
   return yyextra->yyLineNr;
 }
 
-#if USE_STATE2STRING
 #include "doctokenizer.l.h"
-#endif

src/fortrancode.l

@@ -74,8 +74,6 @@ typedef yyguts_t *yyscan_t;
 #define YY_NO_INPUT 1
 #define YY_NO_UNISTD_H 1
 
-#define USE_STATE2STRING 0
-
 /*
  * For fixed formatted code position 6 is of importance (continuation character).
  * The following variables and macros keep track of the column number
@@ -178,9 +176,7 @@ struct fortrancodeYY_state
    int fixedCommentAfter = 72;
 };
 
-#if USE_STATE2STRING
-static const char *stateToString(int state);
-#endif
+[[maybe_unused]] static const char *stateToString(int state);
 
 static bool getFortranNamespaceDefs(const QCString &mname,
                                NamespaceDef *&cd);
@@ -1600,6 +1596,4 @@ static inline void pop_state(yyscan_t yyscanner)
 }
 //---------------------------------------------------------
 
-#if USE_STATE2STRING
 #include "fortrancode.l.h"
-#endif

src/lexcode.l

@@ -46,8 +46,6 @@ typedef yyguts_t *yyscan_t;
 #define YY_NO_INPUT 1
 #define YY_NO_UNISTD_H 1
 
-#define USE_STATE2STRING 0
-
 struct lexcodeYY_state
 {
      OutputCodeList *code;
@@ -93,9 +91,7 @@ struct lexcodeYY_state
      const char   *currentFontClass;
 };
 
-#if USE_STATE2STRING
-static const char *stateToString(int state);
-#endif
+[[maybe_unused]] static const char *stateToString(int state);
 
 static void setCurrentDoc(yyscan_t yyscanner,const QCString &anchor);
 static void startCodeLine(yyscan_t yyscanner);
@@ -1284,6 +1280,4 @@ void LexCodeParser::parseCode(OutputCodeList &codeOutIntf,
 
 //---------------------------------------------------------------------------------
 
-#if USE_STATE2STRING
 #include "lexcode.l.h"
-#endif