RE: Extensible Records

2007-11-12 Thread Simon Peyton-Jones
| There seems to be widespread agreement that the current situation wrt | records is unacceptable, but the official GHC policy is that there are too | many good ideas to choose from - so nothing gets done! I hence humbly | propose that

Re: Extensible Records

2007-11-12 Thread Claus Reinke
reports!-). i've also added the three language and implementation features i consider most important to make library-based extensible records useable in practice (none of which happen to be specific to records, btw;-). in trying to be comprehensive (mostly to explore the limitations of my approach

Re: Extensible Records

2007-11-12 Thread Barney Hilken
I've tried to summarise the important differences between the various proposals on the wiki page, but it still needs lots of illustrative examples. Anyone who is interested, please contribute! Barney. ___ Glasgow-haskell-users mailing list

Re: Extensible Records

2007-11-11 Thread Voldermort
I've entered a feature request for this on Trac http://hackage.haskell.org/trac/ghc/ticket/1866 ___ Glasgow-haskell-users mailing list Glasgow-haskell-users@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-users

Re: Extensible Records

2007-11-11 Thread Barney Hilken
I think this would be a BIG mistake. Whatever system GHC settles on is almost certain to become part of the Haskell standard, and this particular system has some deep limitations which could not be got round without ripping it all out and starting again. The problem with this (and other

Re[2]: Extensible Records

2007-11-11 Thread Bulat Ziganshin
Hello Barney, Sunday, November 11, 2007, 2:34:14 PM, you wrote: An important application which is made impossible by this approach is i propose to start Records project by composing list of requirements/applications to fulfill; we can keep it on Wiki page. this will create base for language

Re: Extensible Records

2007-11-11 Thread Ian Lynagh
On Sat, Nov 10, 2007 at 11:24:24PM +, Voldermort wrote: I assume that porting an existing implementation would be much easier than starting from scratch. I doubt this is true, but even if it is I would prefer to see features chosen based on their merits. (I'm not familiar with the

Re: Extensible Records

2007-11-11 Thread Stefan O'Rear
On Sun, Nov 11, 2007 at 03:02:56PM +0300, Bulat Ziganshin wrote: Hello Barney, Sunday, November 11, 2007, 2:34:14 PM, you wrote: An important application which is made impossible by this approach is i propose to start Records project by composing list of requirements/applications to

Re: Extensible Records

2007-11-11 Thread Claus Reinke
Whatever system GHC settles on is almost certain to become part of the Haskell standard, and this particular system has some deep limitations which could not be got round without ripping it all out and starting again. i'd like to have extensible records, but i'd rather like to decompose

Re: Extensible Records

2007-11-11 Thread Barney Hilken
Hugs.Trex :t let f opts x = (opt1=default|opts) in f let {...} in f :: a\opt1 = Rec a - b - Rec (opt1 :: [Char] | a) This completely loses the aim of optional arguments: with this type, the argument 'opts' cannot have a field 'opt1' (as shown by the context 'a\opt1'). The type we want

Re: Extensible Records

2007-11-11 Thread Claus Reinke
should say that 'opts' cannot have any fields except 'opt1' (though that is optional). Flex cannot express this type. ok, then i misunderstood what you wanted to demonstrate with that example. but then this part doesn't seem to need any extensible records at all, in fact 'cannot have any fields

Re: Extensible Records

2007-11-11 Thread Voldermort
Bulat Ziganshin wrote: i propose to start Records project by composing list of requirements/applications to fulfill; we can keep it on Wiki page. Wiki page duly created http://hackage.haskell.org/trac/ghc/wiki/ExtensibleRecords ___

RE: Extensible Records

2007-11-10 Thread Seth Kurtzberg
] On Behalf Of Voldermort Sent: Saturday, November 10, 2007 6:24 PM To: glasgow-haskell-users@haskell.org Subject: Extensible Records Is there any chance of seeing extensible records in GHC 6.10? There seems to be widespread agreement that the current situation is unacceptable, but the official GHC

RE: Extensible Records

2007-11-10 Thread Seth Kurtzberg
I misread it as 6.1. Sorry about that. -Original Message- From: Stefan O'Rear [mailto:[EMAIL PROTECTED] Sent: Saturday, November 10, 2007 6:55 PM To: Seth Kurtzberg Cc: 'Voldermort'; glasgow-haskell-users@haskell.org Subject: Re: Extensible Records On Sat, Nov 10, 2007 at 06:35:34PM

Re: Extensible Records

2007-11-10 Thread Stefan O'Rear
On Sat, Nov 10, 2007 at 06:35:34PM -0500, Seth Kurtzberg wrote: 6.10? I think that's a typo as the current version is 6.8.1. Or did I misunderstand what you were saying? 6.8.1 is released, there is abolutely no way new features are going to enter a published version. Hence, 6.10. Stefan

Re: Extensible Records

2007-11-10 Thread Stefan O'Rear
On Sat, Nov 10, 2007 at 06:35:34PM -0500, Seth Kurtzberg wrote: Is there any chance of seeing extensible records in GHC 6.10? There seems to be widespread agreement that the current situation is unacceptable, but the official GHC policy is that there are too many good ideas to choose from

Re[2]: Extensible Records

2007-11-10 Thread Bulat Ziganshin
Hello Stefan, Sunday, November 11, 2007, 2:54:51 AM, you wrote: Is there any chance of seeing extensible records in GHC 6.10? I second this request +1 -- Best regards, Bulatmailto:[EMAIL PROTECTED] ___ Glasgow-haskell

Re: FAQ: How to Use Extensible Records in GHCi

2004-03-30 Thread Alastair Reid
Is the feature described in the paper just a proposal or is there a switch somethere to enable it? I think you used the wrong compiler. It's called Hugs :-) Prelude #a ( a='a', b=True ) ERROR - Trex.insertField not in scope *** Possible cause: Trex module not imported Prelude :l Trex Trex

FAQ: How to Use Extensible Records in GHCi

2004-03-29 Thread S. Alexander Jacobson
I feel like I have way too much code of the form: changeGpart (C a b c d e f g h i) g' = C a b c d e f g' h i So, I got excited reading Simon and Mark's Lightweight Extensible Records For Haskell paper as a way to get rid of this cruft. I immediately started GHCi, typed {a=Hello

Re: Re : Extensible records in Haskell

2002-11-07 Thread Adrian Hey
On Wednesday 06 November 2002 10:48 pm, Nicolas Oury wrote: I am going to try to persuade you: * first of all, it seems to be needed in order to make first class modules (cf your paper) . And I think that a true module system would be useful. But I may be wrong. * As far as I am concerned,

Re: Re: Extensible records in Haskell

2002-11-07 Thread Keean Schupke
Thanks, have read the paper, however also saw the paper by Simon Peyton-Jones and Mark Jones on Lightweight Extensible Records for Haskell, which I think Simon refered to in an earlier post... would it not be better to have this instead? Regards, Keean Schupke. Alastair Reid wrote

Re: Re : Extensible records in Haskell

2002-11-07 Thread Nicolas Oury
I just read your proposal for lightweight extensible records for Haskell and find it great. But I just wonder : why not keeping both records systems (Haskell 98 and extensible) with their own syntax, introducing for example [{..}] for extensible records for example. This would resolve

Re : Extensible records in Haskell

2002-11-06 Thread Nicolas Oury
Hello, is there something like extensible records in ghc? Are you wanting something like Hugs' T-Rex or did you have something else in mind? Hello, For what I understand of T-Rex it is what I wait. I need something that can allow to use records without declaring their type first

Re : Extensible records in Haskell

2002-11-06 Thread Keean Schupke
: Hello, is there something like extensible records in ghc? Are you wanting something like Hugs' T-Rex or did you have something else in mind? Hello, For what I understand of T-Rex it is what I wait. I need something that can allow to use records without declaring their type first and that can

Re: Re : Extensible records in Haskell

2002-11-06 Thread Nicolas.Oury
not sure I get you but I was thinking of staticly typed extensible records, like in T-Rex. In fact, I need less than that. I think that not declared records, like in SML are sufficient for me. Best regards, Nicolas Regards, Keean Schupke. Nicolas Oury wrote: Hello

Re: Re : Extensible records in Haskell

2002-11-06 Thread Alastair Reid
Just a quick point, which I'm sure you realise, but static typing gives you guarantees about the runnability of a program that dynamic typing breaks... Which, presumably, is why he wants T-Rex which gives strong typing and extensible records and comes from the same great source (MP Jones

Re: Re : Extensible records in Haskell

2002-11-06 Thread Nicolas Oury
names some fields that should have the same name. * ... I could try find other reasons tomorrow. Simon | -Original Message- | From: Nicolas Oury [mailto:Nicolas.Oury;ens-lyon.fr] | Sent: 06 November 2002 08:38 | To: [EMAIL PROTECTED] | Subject: Re : Extensible records in Haskell

Extensible records in Haskell

2002-11-05 Thread Nicolas Oury
Hello, is there something like extensible records in ghc? Is it planed to? Can anyone help? Best regards, Nicolas Oury ___ Glasgow-haskell-users mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/glasgow-haskell-users

Re: Extensible records in Haskell

2002-11-05 Thread Alastair Reid
Hello, is there something like extensible records in ghc? Are you wanting something like Hugs' T-Rex or did you have something else in mind? -- Alastair Reid [EMAIL PROTECTED] Reid Consulting (UK) Limited http://www.reid-consulting-uk.ltd.uk/alastair