burkhard@software.org (Neil Burkhard) (09/20/90)
I'm trying to use yacc/lex in a program I'm developing in C++ using Apollo's C++ system. Can anybody shed some light on how I can have the yacc action routines invoke C++ routines? Not obvious how I can have the compiler figure out the proper names since C++ mangles them. Note: everything is in C++ (including 'main') except yacc/lex stuff. Thanks in advance for any helpful comments. -- --------------------------------------------------------------- Neil Burkhard Internet: burkhard@software.org Software Productivity Consortium Phone: 703-742-7154 2214 Rock Hill Road Herndon, VA 22070 "Just when you think you're on easy street, someone rips up the pavement"
aardvark@cooper.cooper.EDU (Rob Horn ) (09/20/90)
interfacing C++ with Yacc is messy, but easily done.
Yacc itself produces C code with the users actions imbedded in it
unchanged. Yacc does not care if your actions are valid C
since C++ is a superset of C, the Yacc/Lex generated code can be compiled
with the C++ compiler. example:
%token SPAM MOOSE FOOBAR . . .
ferret : SPAM MOOSE
{ // C++ code }
| SPAM SPAM
{ // C++ code }
;
%%
Yacc will completely ignore what the actions you give it are and will put
them unchanged into the file it produces.
The version of Yacc I have used produces an old style C code, and thus the
C++ compiler will print out a bunch of horrible warnings
"warning: yyparse() old style declaration. type int assumed. " and such,
but will produce no errors, provided the actions are acceptable C++ code.rich@Rice.edu (Richard Murphey) (09/20/90)
In article <1635@software.software.org> burkhard@software.org (Neil Burkhard) writes:
I'm trying to use yacc/lex in a program I'm developing in C++
using Apollo's C++ system. Can anybody shed some light on
how I can have the yacc action routines invoke C++ routines? Not
obvious how I can have the compiler figure out the proper names since
C++ mangles them. Note: everything is in C++ (including 'main')
except yacc/lex stuff.
I have the beginnings of an extension language written in g++, bison
and flex (free C++, yacc and lex workalikes). The sources are on
qed.rice.edu (128.42.4.38) in /pub/interp-1.9.tar.Z and are
distributed under the GPL. The texinfo sources for the documentation
are included.
The bison (or yacc) output is compiled with g++; all you need is a
define or two to take into account the differences in I/O.
Any comments or suggestions on interp-1.9 are welcome! Richolson@sax.cs.uiuc.edu (Bob Olson) (09/20/90)
I have a perl script that will create a c++ class from yacc or lex output. It is not yet entirely solid, but it does seem to work (I'll be working on it more when my project actually gets to the point at which the parser'll be used). It is available for anonymous ftp on a.cs.uiuc.edu in tmp/olson/gen.shar. --bob
vasta@apollo.HP.COM (John Vasta) (09/21/90)
In article <1635@software.software.org> burkhard@software.org (Neil Burkhard) writes: >I'm trying to use yacc/lex in a program I'm developing in C++ >using Apollo's C++ system. Can anybody shed some light on >how I can have the yacc action routines invoke C++ routines? Not >obvious how I can have the compiler figure out the proper names since >C++ mangles them. Note: everything is in C++ (including 'main') >except yacc/lex stuff. The next release of Domain/OS (SR10.3) on the Apollo contains modified versions of lex/yacc which produce output that can be compiled by the C++ compiler (the only problems were with function prototypes). In that case, you can put C++ code directly in the parser actions and just compile the output as a C++ source file. SR10.3 is due out soon, I believe, but I don't know the exact date. John Vasta Hewlett-Packard Apollo Systems Division vasta@apollo.hp.com M.S. CHR-03-DW (508) 256-6600 x5978 300 Apollo Drive, Chelmsford, MA 01824 UUCP: {decwrl!decvax, mit-eddie, attunix}!apollo!vasta