Re: About C++ and flex

[Hans Aberg]

At 21:03 +0100 2001/11/22, Laurent Mascherpa wrote:
>When input codes where small there was no visible speed problem. But
>compared to parser produced without -+, with the exact same rules, it
>was really much slower, especially on larger input codes (> 200 lines).
>I did not take time to find why, but directly switched to /classical/
>way of using Flex.

I realize now that the example I posted is compiled without the Flex -+
option. :-) I therefore have to go back to my files, to see if I can find a
genuine Flex C++ example.

I have a vague memory that Flex's C++ style, where its header is read two
times using macros, is sometimes causing problems. So for that reason, I
switched to compile under C, and merely make a C++ wrap which would give a
neat interface to my other C++ code.

Perhaps one should look for a better Flex C++ style by synching its C++
support with the Bison C++ support we now expect to emerge.

  Hans Aberg