On Mon, Jan 15, 2007 at 04:52:37PM -0700, Bob Proulx wrote: > Multiple flex generated scanners are giving me trouble with duplicate > symbols. I am using automake-1.10. > > What is the best practice for organizing a program that includes > multiple lex generated scanners? > > I am using the recommended practice of using defines to rename all of > the yacc/lex symbols as described in the automake manual > (e.g. "#define yylex c_lex", "#define yyerror c_error", etc.) for the > yacc generated parser. The problem I encounter is that yyin is hard > to get redefined. Flex outputs a definition for it before outputing > my define for it in the top of the scan.l file. > > Basically what I have looks like this: > > myprog_SOURCES = parse.y scan.l > BUILT_SOURCES = parse.c parse.h scan.c > AM_YFLAGS = -d > > That is all well and good but then yyin is a global symbol defined by > the flex generated scanner. This appears before I can redefine it > inside the source. > > I guess I can add an AM_CPPFLAGS=-Dyyin=myprogin and list out all of > the symbols to redefine there. But that fails to work if I have two > flex generated scanners in the same directory. I would rather find a > more general solution. > > If I add an option to flex to rename the symbols like this then the > scanner flex generates renames the symbols for me. > > AM_LFLAGS = -l -Pmyprog > > But in this case ylwrap fails because -P also renames the output file > to lex.myprog.c and ylwrap fails to find the produced file. And it > has the same problem of failing if there are two flex generated > scanners in the same directory. > > I am about ready to write a custom rule to sed the generated file. I > am sure that will work but I must be missing something obvious since > this is a common enough problem that there must be a standard > solution that I am missing.
I have a program that use 17 flex scanners (and 17 grammatical analysers) to detect/parse biological sequence and alignement formats. I encountered the same problem ... and made the following constructs that did the trick (at least for me). AUTOMAKE_OPTIONS = subdir-objects AM_YFLAGS = -d -p `basename $* | sed 's,y$$,,'` AM_LFLAGS = -s -P`basename $* | sed 's,l$$,,'` -olex.yy.c [...] CLU_SRC = align/clustal.c align/clustaly.y align/clustall.l CLU_HDR = align/clustal.h EMB_SRC = sequence/embl.c sequence/embly.y sequence/embll.l EMB_HDR = sequence/embl.h FAS_SRC = sequence/fasta.c sequence/fastay.y sequence/fastal.l FAS_HDR = sequence/fasta.h [...] Hope this helps, Regards. -- Nicolas Joly Biological Software and Databanks. Institut Pasteur, Paris.
