“Chat with Brian Regarding Lexers and Parser Generators”

remember we were looking for Unicode-savvy parsing tools a while back?

I do

I'm looking for new parser-generator tools for my project at work

came across this: http://www.devincook.com/goldparser/about/why-use-gold.htm

oh man, very interesting

I suspect that the author is more mindful of capability than performance

still, I plan to download it and try a small grammar with GOLD

I'll also try out ANTLR (again) and ACCENT (http://accent.compilertools.net/)

(why do all of these tools use all-caps names? dunno.)

ANTLR is an acronym, I don't know about the rest

not that it matters much

yeah

I know ANTLR made some more progress, but I haven't played with it.

heh. Check out the first News Item on the ANTLR home page

bah, GOLD is Win32-only.

Grr.

This whole class of software is a joke.

2009?! we're going to have to wait a long time for that next beta.

But the news is in past tense! I think they're probably just thousands of timezones ahead of us. That would explain it.

heh

yeah, there's not much out there that's free. I've found a bunch of commercial tools, but none of them have even inspired me to request a trial version

again, I see that ANTLR's C++ target is dormant. http://www.antlr.org:8080/pipermail/antlr-interest/2007-January/019001.html

that's very relevant, thank you

Looking at this stuff never makes me happy. :-(

no kiddin'

well, that just left me with a grand total of zero tools to investigate. lame.

I think, "I could devote a ton of my time to learning the issues and helping to fix these problems. Or I could make a living and have a life, and make do with what I already have."

yep

But it still makes me nuts. My work could really benefit from a good, Unicode-savvy parser generator.

with a C++ target

yeah. the thing that got me started on this (for Agilent) was how poorly designed lex/yacc (and flex/bison) are for providing code to be part of a larger project

they were designed for making a standalone executable that doesn't need to do much more beyond the parsing, it seems

they're specifically for feeding a compiler, right?

our simulator already has six lex/yacc-based parsers in the code, and we end up having to mangle the yy___ symbols and other globals to even just make it link

(a particular kind of compiler/builder, I mean)

yeah

Hey, do you mind if I post this conversation on [tw]? I'll hide your handle.

oh right, and my other gripe was memory management. Suppose we're parsing through a line and allocating memory for various things as we go. Then we hit a syntax error. There are ways to design the rules to do error recovery, but designing the rules to allow error recovery to clean up all allocated memory is not obvious at all.

go for it

thanks