[Mono-list] VB Language (was: I want to get in on this.)

Bob Salita Bob_Salita@SoftworksLtd.com
Thu, 12 Jul 2001 21:18:00 -0500

>Jay wrote:
>The trick mentioned of munging the tokens before they
>hit the grammar parser is actually a rather commonly mentioned one.  To get
>an idea of how lucrative a yacc grammar for VB is, you really have to read
>the numerous requests for one in comp.compilers,
>comp.lang.basic.visual.misc, and comp.lang.basic.visual.3rdparty over the
>last 5 years and the replies explaning that there isn't one available and
>simple explanations as to why.
>The people who have parsers for it all claimed they were hard to build, 
>they did the munging trick or went with something other than yacc, and that
>they were now proprietary and weren't going to be released as too much
>effort was put into them.

There's an ad in the current (August) issue of VBPJ offering VB parser 
services (but not a product) and even in creating VB implementations on 
non-Windows platforms. To my knowledge, that's the only vendor in that type 
of biz.

>Something to point out is that I, myself, never really learned much about
>grammars, and most of what I know are from crash courses of trying to write
>a VB6 parser a few months ago that involved reading the beginning of a book
>on ANTLR that explained what the limitations of LALR parsers (such as yacc
>are) and why a predicated-LL(k) can parse more languages.  I might be very
>wrong on some of my direct appraisals (such as Miguel's example, which I
>feel would not work as it doesn't seem left recursive), and I hope no one
>holds it that against me.

Me too. I've always assumed parsers were for people who don't write 
compilers ;-)

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