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Applications using Lex/Flex & Yacc/Bison

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  Applications using Lex/Flex & Yacc/Bison Partha S Panda <parthaspanda2005@yahoo.com> - 2013-11-07 23:40 -0800
    Re: Applications using Lex/Flex & Yacc/Bison Timothy Knox <tdk@thelbane.com> - 2013-11-08 14:12 -0800
    Re: Applications using Lex/Flex & Yacc/Bison Hans-Peter Diettrich <DrDiettrich1@aol.com> - 2013-11-09 05:42 +0100
      Re: Applications using Lex/Flex & Yacc/Bison mac <acolvin@efunct.com> - 2013-11-13 19:23 +0000
    Re: Applications using Lex/Flex & Yacc/Bison Tero Koskinen <tero.koskinen@iki.fi> - 2013-12-05 19:09 +0200

#1030 — Applications using Lex/Flex & Yacc/Bison

Hi,

    I am trying to figure out hardware or software applications other then
    compiler-related  that utilize yacc/bison and lex/flex respectively.

    This will help me register the range of these tools.

    Anyone curious enough to help ?

Regards,
Partha Sarathi Panda.

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#1033

Somewhere on Shadow Earth, at Thu, Nov 07, 2013 at 11:40:54PM -0800, Partha S Panda wrote:
>     I am trying to figure out hardware or software applications other then
>     compiler-related  that utilize yacc/bison and lex/flex respectively.
>
>     This will help me register the range of these tools.

At my last gig, we used flex for teasing apart browser user agent
strings, for determining client capabilities.

--
Timothy Knox <mailto:tdk@thelbane.com>

I like to say that in the old days, if you reinvented the wheel,
you would get your wrist slapped for not reading. But nowadays
people are reinventing the flat tire. I'd personally be happy if
they reinvented the wheel, because at least we'd be moving forward.
    -- Alan Kay

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#1034

Partha S Panda schrieb:
> Hi,
>
>     I am trying to figure out hardware or software applications other then
>     compiler-related  that utilize yacc/bison and lex/flex respectively.

Do you mean existing programs, or what *could* be done?

Most applications I know of use other parsers, not lex/yacc. It would be
interesting, though, *why* they use other parsers. I could imagine that
e.g. counting words or sentences in natural language text could be done
using lex/yacc, but would be easier to accomplish, and faster, by other
parser techniques.

In general lex/yacc allows to parse whatever can be represented in an LR
(LALR(1)?) grammar, but not all grammars are acceptable due to
restrictions (ambigous...). This could be any formatted data, like BNF,
HTML, RTF, TEX, phonebooks, log files, man/info files, or (textual)
output of many other programs. I'm not sure whether binary data can be
parsed as well, it may be necessary to modify lex/flex for that purpose.
Many other parsers come with example grammars that can *not* be used
with lex/yacc.

DoDi

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#1039

>>     I am trying to figure out hardware or software applications other then
>>     compiler-related  that utilize yacc/bison and lex/flex respectively.

One recent example that comes to mind is "undns", which uses tables to map
internet router DNS names to geographic locations. The tables  are parsed
with lex/yacc.

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#1060

Hi,

On Thu, 7 Nov 2013 23:40:54 -0800 (PST)
Partha S Panda <parthaspanda2005@yahoo.com> wrote:

> Hi,
>
>     I am trying to figure out hardware or software applications other then
>     compiler-related  that utilize yacc/bison and lex/flex respectively.

OpenBSD uses yacc/lex quite much in various places, like in packet filter (pf/pfctl), OpenSMTPD, etc.

On installed OpenBSD system you can run command
find /usr/src -name parse.y
to see all the places where yacc is used.

--
Tero Koskinen <tero.koskinen@iki.fi>

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