• Andrei Alexandrescu (33/33) Nov 18 2018 Hello, Akim Demaille, the maintainer of the famed GNU Bison parser
• Bastiaan Veelo (22/60) Nov 18 2018 Without ever having seen a parser generated by the Bison D
• Manu (14/47) Nov 18 2018 I use Bison in a D project, but since it emits C/C++, I use an
• Manu (5/64) Nov 18 2018 That said, to your question, I have no experience with the Bison D
• Carl Sturtivant (2/8) Nov 27 2018 I'd like to try out the existing D backend too! Exciting news!
• H. S. Teoh (13/23) Nov 21 2018 [...]

Andrei Alexandrescu <SeeWebsiteForEmail erdani.org> writes:

Hello, Akim Demaille, the maintainer of the famed GNU Bison parser 
generator, reached out to me with the following (published with his accord):

====
I’m the maintainer of GNU Bison, which is a parser generator for C/C++ 
and Java.  A few years ago someone contributed a D backend for Bison, 
but at that time, the investment in Bison was low.  Now I’m spending 
time on it, and Richard Stallman asked me to contact the « D community » 
to know whether there would be interest for such a backend.

Bison is a LALR(1), LR(1), IELR(1) and GLR parser generator.  It’s based 
on ye olde yacc, by it features several interesting properties.

Of course the D world already features several parser generators, some 
being even embedded in the language and benefiting from compile time 
function evaluation.  So it’s very unclear to me if Bison would get some 
interest.

What would you think about that?
====

I wrote back that Bison is currently much more sophisticated than the 
present alternatives in the D community, and that we'd be interested in 
continued maintenance of the D backend for Bison. Further discussion 
revealed:

====
I would say that my first and foremost worry would be to integrate 
something which is not used, and not maintained.  And I am not a D 
programmer, so I would not be able to decide whether his work was good 
or not, have it evolve with Bison and releases of D.

Also, something that somewhat worries me is that the D parser was based 
on the Java parser, not the C++ one.
====

More thoughts and reports from the community would be helpful. If you 
are a current or former Bison user with the D backend, or if you have an 
interest in contributing reviews and patches for it,  please chime in.


Thanks,

Andrei

Bastiaan Veelo <Bastiaan Veelo.net> writes:

On Sunday, 18 November 2018 at 15:56:47 UTC, Andrei Alexandrescu 
wrote:
 Hello, Akim Demaille, the maintainer of the famed GNU Bison 
 parser generator, reached out to me with the following 
 (published with his accord):

 ====
 I’m the maintainer of GNU Bison, which is a parser generator 
 for C/C++ and Java.  A few years ago someone contributed a D 
 backend for Bison, but at that time, the investment in Bison 
 was low.  Now I’m spending time on it, and Richard Stallman 
 asked me to contact the « D community » to know whether there 
 would be interest for such a backend.

 Bison is a LALR(1), LR(1), IELR(1) and GLR parser generator.  
 It’s based on ye olde yacc, by it features several interesting 
 properties.

 Of course the D world already features several parser 
 generators, some being even embedded in the language and 
 benefiting from compile time function evaluation.  So it’s very 
 unclear to me if Bison would get some interest.

 What would you think about that?
 ====

 I wrote back that Bison is currently much more sophisticated 
 than the present alternatives in the D community, and that we'd 
 be interested in continued maintenance of the D backend for 
 Bison. Further discussion revealed:

 ====
 I would say that my first and foremost worry would be to 
 integrate something which is not used, and not maintained.  And 
 I am not a D programmer, so I would not be able to decide 
 whether his work was good or not, have it evolve with Bison and 
 releases of D.

 Also, something that somewhat worries me is that the D parser 
 was based on the Java parser, not the C++ one.
 ====

 More thoughts and reports from the community would be helpful. 
 If you are a current or former Bison user with the D backend, 
 or if you have an interest in contributing reviews and patches 
 for it,  please chime in.


 Thanks,

 Andrei

Without ever having seen a parser generated by the Bison D 
backend, and my last use of Bison itself being close to two 
decades ago, I too think that Bison’s sophistication is not yet 
matched by current D parser generators. We do have generators 
that are easier to use than Flex+Bison, which probably makes it 
more difficult to generate interest in (maintaining) a D backend. 
With the ever increasing C++ compatibility of D it would be 
interesting to know if and how well a parser generated by the C++ 
backend would work. Nevertheless I would expect that a dedicated 
D backend can produce nicer parsers with a nicer interface. 
Regarding being based on the Java backend: If the C++ backend 
relies on the preprocessor (I don’t remember) then that may be 
the reason why (as dpp did not yet exist). It would be 
interesting to know why being based on that backend is worrisome; 
What downsides does that imply?

I don’t think that I will be able to get involved in Bison (too 
far in development using Pegged) but parsers are fun and I hope 
that others have more valuable input on this matter.

Regards,
Bastiaan.

Manu <turkeyman gmail.com> writes:

I use Bison in a D project, but since it emits C/C++, I use an
elaborate extern(C++) based solution to interact with the Bison
output.
The binding layer is hard to maintain, and I don't work on the project
much because of the friction.

I evaluated the native D parsers, but quickly switched back to Bison
because it just works, and works very well.
I was also motivated by the fact the parser also had C++ output, since
writing any project exclusively in D is a risk, and reverting to C++
is always a possibility in the event D fails.

I can say for certain, if Bison emit D output, I would use it, and get
much value from it!

On Sun, Nov 18, 2018 at 8:00 AM Andrei Alexandrescu via Digitalmars-d
<digitalmars-d puremagic.com> wrote:
 Hello, Akim Demaille, the maintainer of the famed GNU Bison parser
 generator, reached out to me with the following (published with his accord):

 ====
 I’m the maintainer of GNU Bison, which is a parser generator for C/C++
 and Java.  A few years ago someone contributed a D backend for Bison,
 but at that time, the investment in Bison was low.  Now I’m spending
 time on it, and Richard Stallman asked me to contact the « D community »
 to know whether there would be interest for such a backend.

 Bison is a LALR(1), LR(1), IELR(1) and GLR parser generator.  It’s based
 on ye olde yacc, by it features several interesting properties.

 Of course the D world already features several parser generators, some
 being even embedded in the language and benefiting from compile time
 function evaluation.  So it’s very unclear to me if Bison would get some
 interest.

 What would you think about that?
 ====

 I wrote back that Bison is currently much more sophisticated than the
 present alternatives in the D community, and that we'd be interested in
 continued maintenance of the D backend for Bison. Further discussion
 revealed:

 ====
 I would say that my first and foremost worry would be to integrate
 something which is not used, and not maintained.  And I am not a D
 programmer, so I would not be able to decide whether his work was good
 or not, have it evolve with Bison and releases of D.

 Also, something that somewhat worries me is that the D parser was based
 on the Java parser, not the C++ one.
 ====

 More thoughts and reports from the community would be helpful. If you
 are a current or former Bison user with the D backend, or if you have an
 interest in contributing reviews and patches for it,  please chime in.


 Thanks,

 Andrei

Manu <turkeyman gmail.com> writes:

On Sun, Nov 18, 2018 at 10:41 PM Manu <turkeyman gmail.com> wrote:
 On Sun, Nov 18, 2018 at 8:00 AM Andrei Alexandrescu via Digitalmars-d
 <digitalmars-d puremagic.com> wrote:
 Hello, Akim Demaille, the maintainer of the famed GNU Bison parser
 generator, reached out to me with the following (published with his accord):

 ====
 I’m the maintainer of GNU Bison, which is a parser generator for C/C++
 and Java.  A few years ago someone contributed a D backend for Bison,
 but at that time, the investment in Bison was low.  Now I’m spending
 time on it, and Richard Stallman asked me to contact the « D community »
 to know whether there would be interest for such a backend.

 Bison is a LALR(1), LR(1), IELR(1) and GLR parser generator.  It’s based
 on ye olde yacc, by it features several interesting properties.

 Of course the D world already features several parser generators, some
 being even embedded in the language and benefiting from compile time
 function evaluation.  So it’s very unclear to me if Bison would get some
 interest.

 What would you think about that?
 ====

 I wrote back that Bison is currently much more sophisticated than the
 present alternatives in the D community, and that we'd be interested in
 continued maintenance of the D backend for Bison. Further discussion
 revealed:

 ====
 I would say that my first and foremost worry would be to integrate
 something which is not used, and not maintained.  And I am not a D
 programmer, so I would not be able to decide whether his work was good
 or not, have it evolve with Bison and releases of D.

 Also, something that somewhat worries me is that the D parser was based
 on the Java parser, not the C++ one.
 ====

 More thoughts and reports from the community would be helpful. If you
 are a current or former Bison user with the D backend, or if you have an
 interest in contributing reviews and patches for it,  please chime in.


 Thanks,

 Andrei

 I use Bison in a D project, but since it emits C/C++, I use an
 elaborate extern(C++) based solution to interact with the Bison
 output.
 The binding layer is hard to maintain, and I don't work on the project
 much because of the friction.

 I evaluated the native D parsers, but quickly switched back to Bison
 because it just works, and works very well.
 I was also motivated by the fact the parser also had C++ output, since
 writing any project exclusively in D is a risk, and reverting to C++
 is always a possibility in the event D fails.

 I can say for certain, if Bison emit D output, I would use it, and get
 much value from it!

That said, to your question, I have no experience with the Bison D
backend (it never occurred to me that such a thing may exist)... just
the C++ backend.
Where are builds to try out?

Carl Sturtivant <sturtivant gmail.com> writes:

On Monday, 19 November 2018 at 06:45:59 UTC, Manu wrote:
 That said, to your question, I have no experience with the 
 Bison D
 backend (it never occurred to me that such a thing may 
 exist)... just
 the C++ backend.
 Where are builds to try out?

I'd like to try out the existing D backend too! Exciting news!

"H. S. Teoh" <hsteoh quickfur.ath.cx> writes:

On Sun, Nov 18, 2018 at 10:56:47AM -0500, Andrei Alexandrescu via Digitalmars-d
wrote:
 Hello, Akim Demaille, the maintainer of the famed GNU Bison parser
 generator, reached out to me with the following (published with his
 accord):
 
 ====
 I’m the maintainer of GNU Bison, which is a parser generator for C/C++
 and Java.  A few years ago someone contributed a D backend for Bison,
 but at that time, the investment in Bison was low.  Now I’m spending
 time on it, and Richard Stallman asked me to contact the « D community
 » to know whether there would be interest for such a backend.

[...]

Yes, I'm interested!  It has been a while since I needed to use bison,
but being able to generate D code from bison would be great for my DSL
projects.

The quality of the generated D code, though, is a tricky question.
Ideally, it should generate an API idiomatic to D, but from what I
remember of bison's generated API, it probably doesn't lend itself very
well to template-heavy range-based code that typical D code would
expect.


T

-- 
Some ideas are so stupid that only intellectuals could believe them. -- George
Orwell