Thanks for the answers! I was obviously thinking to complicated ;-) I have now added a function to the start of processing for each and every token. That function conditionally (depending on command line option settings) outputs a version of everything including "include files" to the specified file. Does the trick rather nicely, albeit at the price of adding ~80 function calls. But that's in a very infrequently changing area, so it doesn't really matter.
I'll probably try out YY_USER_ACTION now that the immediate need is solved. Sounds like a more elegant solution. Thanks again for the quick help! Rainer El vie., 26 abr. 2019 a las 20:22, Jannick (<thirdedit...@gmx.net>) escribió: > > On Fri, 26 Apr 2019 11:26:49 +0200, Rainer Gerhards wrote: > > > I would like to generate that output file during regular configuration > > processing. So in short I need a capability to see each character that > flex > > processes at exactly the time it processes the character. I did not find a > > documented override to do this. > > > > Is there any way to handle this with flex? > > Add 'ECHO;' to the flex rule whose token (yytext) you want to write to > stdout. You might want to check the first example in > https://westes.github.io/flex/manual/Multiple-Input-Buffers.html#Multiple-In > put-Buffers which could be pretty close to what you currently have, but > using flex only, not bison. > > Alternatively, 'gcc -E' could be a starting point which ships the nested > include feature if the keyword 'include' was replaced by '#include'. This > requires the end user to have 'gcc' available, but that should not be an > issue when dealing with 'config.h' I guess. > > Best, > J. > _______________________________________________ help-bison@gnu.org https://lists.gnu.org/mailman/listinfo/help-bison
