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From Michael Franzkowiak <mich...@contiamo.com>
Subject Re: [DISCUSS] ANTLR4 parse template for Calcite ?
Date Thu, 22 Aug 2019 11:04:38 GMT
It is not using ANTLR. Since our goal is specifically to support parsing
and manipulation of SQL in the frontend, we use
https://sap.github.io/chevrotain/docs/ . We're quite happy with that. We
have some pretty big ANTLR grammars for other (non-SQL) use cases and this
approach definitely feels more lightweight.

On Thu, Aug 22, 2019 at 12:22 PM Danny Chan <yuzhao.cyz@gmail.com> wrote:

> Create ! Do you have the ANTLR.g4 file that can be shared ?
>
> Best,
> Danny Chan
> 在 2019年8月22日 +0800 PM5:45,Michael Franzkowiak <michael@contiamo.com>,写道:
> > Danny, what is your web / frontend use case exactly?
> > We've started to create some frontend helpers which you can find at
> > https://github.com/contiamo/rhombic . It's all in a very early state but
> > we'll likely spend some more time on it in the next months. Parsing is
> here
> > https://github.com/contiamo/rhombic/blob/master/src/SqlParser.ts .
> >
> > On Thu, Aug 22, 2019 at 11:38 AM Muhammad Gelbana <m.gelbana@gmail.com>
> > wrote:
> >
> > > I once needed to fix this issue [1] but the fix was rejected because it
> > > introduced worse performance than it ideally should. As mentioned in
> the
> > > comments, the current approach followed in the current parser is the
> reason
> > > for that. I mean if we designed the grammar differently, we could've
> had
> > > fixed the linked issue a long time ago as Julian already attempted to
> fix
> > > it.
> > >
> > > Having that said, we might go with *antlr* only to have that "better"
> > > approach for our parsers. We don't have to dump our current parser of
> > > course as *antlr* can be optionally activated.
> > >
> > > [1] https://issues.apache.org/jira/browse/CALCITE-35
> > >
> > > Thanks,
> > > Gelbana
> > >
> > >
> > > On Thu, Aug 22, 2019 at 10:05 AM Danny Chan <yuzhao.cyz@gmail.com>
> wrote:
> > >
> > > > Thanks, Julian.
> > > >
> > > > I agree this would be a huge work, but I have to do this, I’m just
> > > > wondering if any fellows here have the similar requests.
> > > >
> > > > Best,
> > > > Danny Chan
> > > > 在 2019年8月22日 +0800 PM2:15,Julian Hyde <jhyde@apache.org>,写道:
> > > > > ANTLR isn’t significantly better than, or worse than, JavaCC, but
> it’s
> > > > different. So translating to ANTLR would be a rewrite, and would be a
> > > HUGE
> > > > amount of work.
> > > > >
> > > > >
> > > > >
> > > > > > On Aug 21, 2019, at 8:01 PM, Danny Chan <yuzhao.cyz@gmail.com>
> > > wrote:
> > > > > >
> > > > > > Now some of our fellows want to do the syntax promote in the
WEB
> > > page,
> > > > and they what a parser in the front-page; The ANTLR4 can generate JS
> > > parser
> > > > directly but JAVACC couldn’t.
> > > > > >
> > > > > > So I’m wondering do you have the similar requests ? And do
you
> think
> > > > there is necessity to support ANTLR4 g4 file in Calcite ?
> > > > > >
> > > > > >
> > > > > > Best,
> > > > > > Danny Chan
> > > > >
> > > >
> > >
> >
> >
>

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