Re: [Haskell-cafe] combined parsing pretty-printing
Tillmann, I've been looking into you packages, very neat ideas and a nice implementation really. I've already implemented a toy example and it worked great. Now I am trying to use your library in a more serious piece of code, and I've realised that defineIsomorphisms doesn't support record constructors. To be precise, you handle the case for NormalC in the code, however you do not handle RecC. I don't think this will be a difficult thing to add. Is there any reason for you not to support RecC? Best, 2011/1/26 Tillmann Rendel ren...@informatik.uni-marburg.de Hi Ozgur, Ozgur Akgun wrote: I can write (separately) a parser and a pretty-printer [...] Is there any work to combine the two? Brent Yorgey wrote: Maybe take a look at Invertible Syntax Descriptions: Unifying Parsing and Pretty Printing by Tillmann Rendel and Klaus Ostermann from last year's Haskell Symposium: http://www.informatik.uni-marburg.de/~rendel/unparse/ It's a beautiful paper, and perhaps the code will work for you (although it's too bad it's not on Hackage). Indeed, I started this project for exactly the reason Ozgur describes: I needed to duplicate a lot of information between parsers and pretty printers and was annoyed about it. With invertible syntax descriptions, I now write a single program, which looks like a combinator parser (think Parsec), but can work as a pretty printer, too. I just uploaded the code from the paper (and some additional combinators) to Hackage: http://hackage.haskell.org/package/partial-isomorphisms http://hackage.haskell.org/package/invertible-syntax I use this code for the implementation of some very small languages (think lambda calculus). This works fine. I haven't really tried it for larger languages, but we have two students here in Marburg implementing a parser for Java using the library, so we are going to have experience with larger languages in a few weeks (months?). If you give it a try, I would be happy to receive success stories, bug reports, patches, feature requests etc. I want to keep working on this, and I am open for suggestions. Tillmann ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe -- Ozgur Akgun ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] combined parsing pretty-printing
Great! That was pretty fast :) Are you going to update invertible-syntax to use partial-isomorphisms-0.2? 2011/2/5 Tillmann Rendel tillm...@rendel.net Hi Ozgur, Ozgur Akgun wrote: I've already implemented a toy example and it worked great. Now I am trying to use your library in a more serious piece of code, and I've realised that defineIsomorphisms doesn't support record constructors. To be precise, you handle the case for NormalC in the code, however you do not handle RecC. I don't think this will be a difficult thing to add. Is there any reason for you not to support RecC? No reason at all. I just generalized the Template Haskell macros. They now support: * newtypes * infix constructors * record constructors Infix constructors are only support by constructorIso, though, not by defineIsomorphisms, because I can't think of a good automatic naming scheme. Suggestions welcome. The code is on hackage. There are still some constructors which are not supported: constructors of GADTs as well as data or newtype instances, and constructors with existentials. I would need to think about typing issues before supporting these. Tillmann -- Ozgur Akgun ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] combined parsing pretty-printing
Dear Café, I working on a DSL represented by a algebraic data type with many constructors. I can write (separately) a parser and a pretty-printer for it, and I am doing so at the moment. However, this way it feels like repeating the same information twice. Is there any work to combine the two? Best, Ozgur ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] combined parsing pretty-printing
On Wed, Jan 26, 2011 at 04:22:00PM +, Ozgur Akgun wrote: Dear Café, I working on a DSL represented by a algebraic data type with many constructors. I can write (separately) a parser and a pretty-printer for it, and I am doing so at the moment. However, this way it feels like repeating the same information twice. Is there any work to combine the two? Maybe take a look at Invertible Syntax Descriptions: Unifying Parsing and Pretty Printing by Tillmann Rendel and Klaus Ostermann from last year's Haskell Symposium: http://www.informatik.uni-marburg.de/~rendel/unparse/ It's a beautiful paper, and perhaps the code will work for you (although it's too bad it's not on Hackage). -Brent ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] combined parsing pretty-printing
Tillmann Rendel and Klaus Ostermann. "Invertible syntax descriptions: Unifying parsing and pretty printing".Haskell Symposium 2010.Regards,MalcolmOn 26 Jan, 2011,at 04:22 PM, Ozgur Akgun ozgurak...@gmail.com wrote:Dear Café,I working on a DSL represented by a algebraic data type with many constructors. I can write (separately) a parser and a pretty-printer for it, and I am doing so at the moment. However, this way it feels like repeating the same information twice. Is there any work to combine the two?Best, Ozgur ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] combined parsing pretty-printing
Depending on your concrete syntax, you may be able to use BNFC (http://hackage.haskell.org/package/BNFC). /J On 26 January 2011 17:22, Ozgur Akgun ozgurak...@gmail.com wrote: Dear Café, I working on a DSL represented by a algebraic data type with many constructors. I can write (separately) a parser and a pretty-printer for it, and I am doing so at the moment. However, this way it feels like repeating the same information twice. Is there any work to combine the two? Best, Ozgur ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] combined parsing pretty-printing
On 01/26/2011 05:22 PM, Ozgur Akgun wrote: I working on a DSL represented by a algebraic data type with many constructors. I can write (separately) a parser and a pretty-printer for it, and I am doing so at the moment. However, this way it feels like repeating the same information twice. Is there any work to combine the two? You might want to take a look at [1, 2]XML Picklers from [3]HXT. Steffen [1] http://www.haskell.org/haskellwiki/HXT/Conversion_of_Haskell_data_from/to_XML [2] http://blog.typlab.com/2009/11/writing-a-generic-xml-pickler/ [3] http://hackage.haskell.org/package/hxt-9.0.1 Best, Ozgur ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] combined parsing pretty-printing
Hi Ozgur, Ozgur Akgun wrote: I can write (separately) a parser and a pretty-printer [...] Is there any work to combine the two? Brent Yorgey wrote: Maybe take a look at Invertible Syntax Descriptions: Unifying Parsing and Pretty Printing by Tillmann Rendel and Klaus Ostermann from last year's Haskell Symposium: http://www.informatik.uni-marburg.de/~rendel/unparse/ It's a beautiful paper, and perhaps the code will work for you (although it's too bad it's not on Hackage). Indeed, I started this project for exactly the reason Ozgur describes: I needed to duplicate a lot of information between parsers and pretty printers and was annoyed about it. With invertible syntax descriptions, I now write a single program, which looks like a combinator parser (think Parsec), but can work as a pretty printer, too. I just uploaded the code from the paper (and some additional combinators) to Hackage: http://hackage.haskell.org/package/partial-isomorphisms http://hackage.haskell.org/package/invertible-syntax I use this code for the implementation of some very small languages (think lambda calculus). This works fine. I haven't really tried it for larger languages, but we have two students here in Marburg implementing a parser for Java using the library, so we are going to have experience with larger languages in a few weeks (months?). If you give it a try, I would be happy to receive success stories, bug reports, patches, feature requests etc. I want to keep working on this, and I am open for suggestions. Tillmann ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
