Re: [jflex-users] ambiguities in JFLex syntax grammar from the manual

[Steve R. <sa...@od...>]

José Romildo Malaquias wrote:
> On Mon, Apr 19, 2010 at 12:25:08PM -0400, Steve Rowe wrote:
> [...]
>>  > 3. Can a JFlex comment appear anywhere a space is allowed?
>>
>> Not everywhere; for your specific questions, though:
>>
>>  > For instance, are the following allowed?
>>  >
>>  > %% // end of section 1
>>  >
>>  > %{ // the following will be inserted into the generated class
>>
>> Yes, both of the above are allowed.  After '%%' and '%{' all text is 
>> ignored until end of line - no comment syntax is required.  So these are 
>> allowed too:
>>
>>     %% end of section 1
>>
>>     %{ the following will be inserted into the generated class
> 
> I suppose this applies to every option of the form
> 
>    %[a-z]{
>    %[a-z]}
> 
> like %eofval{ and %eofval}. Right?

Yes.

Starting at line 274 of LexScan.flex:

<MACROS> 
("%{"|"%init{"|"%initthrow{"|"%eof{"|"%eofthrow{"|"%yylexthrow{"|"%eofval{").*{NL}
                           { string.setLength(0); yybegin(COPY); }
<COPY> {
   "%}".*{NL}  { classCode = conc(classCode,string); yybegin(MACROS); }
   "%init}".*{NL} { initCode = conc(initCode,string); yybegin(MACROS); }
   "%initthrow}".*{NL} { initThrow = concExc(initThrow,string); 
yybegin(MACROS); }
   "%eof}".*{NL} { eofCode = conc(eofCode,string); yybegin(MACROS); }
   "%eofthrow}".*{NL} { eofThrow = concExc(eofThrow,string); 
yybegin(MACROS); }
   "%yylexthrow}".*{NL} { lexThrow = concExc(lexThrow,string); 
yybegin(MACROS); }
   "%eofval}".*{NL} { eofVal = string.toString(); yybegin(MACROS); }

   .*{NL}           { string.append(yytext()); }


Steve