[Haskell] Research Job: Compositional Analysis for Mobility & Concurrency @ Heriot-Watt U., Scotland, UK

Research Position ULTRA group (Useful Logics, Types, Rewriting, and their Automation) Computer Science Department School of Mathematical and Computer Sciences Heriot-Watt University

[Haskell] RE: GADTs and GHC

Dear Hakellions PS: In my message about uses of GADTs I asked | ... | d) send Omega code, which GHC won't understand, but which | demonstrates some cunning use of GADTs | All of these would be useful, even (c) and (d) --- we can eyeball the code. I should have also asked you to send exa

[Haskell] multiple occurence of the same type variable in instance head

Hello, the following is not Haskell 98: class C a instance C (a,a) Well, GHC allows this with the -fglasgow-exts flag. Surprisingly, I cannot find a section in the GHC User's Guide which states that -fglasgow-exts can be used to allow this kind of instance declarations. Well

[Haskell] really undecidable instances?

Hello, what ist the problem with instance declarations like the following: instance C Int a => D Char [a] Why are such declarations only allowed with -fallow-undecidable-instances in GHC? How can they result in undecidability? Best wishes, Wolfgang

[Haskell] instance C (a -> a)

Lieber Herr Bachmann, instance-Deklarationen der Form instance C (a -> a) sind tatsächlich nicht konform zum Haskell-98-Standard, ebensowenig instance C (a,a) und dergleichen, was heißt, dass diese Einschränkung nichts mit dem Funktionstyp zu tun hat. Generell darf ein und die

RE: [Haskell] really undecidable instances?

This one can't. But it's hard to formulate a general rule. -fallow-undecidable-instances simply says that you, the programmer, take responsibility for termination. Without the flag, GHC uses a simple but sometimes over-conservative rule Simon | -Original Message- | From: [EMAIL PROTECTE

Re: [Haskell] instance C (a -> a)

Sorry, this mail was not intended for the list. :-( Best wishes, Wolfgang ___ Haskell mailing list Haskell@haskell.org http://www.haskell.org/mailman/listinfo/haskell

Re: [Haskell] really undecidable instances?

Am Montag, 17. Oktober 2005 15:57 schrieben Sie: > This one [That is the instance declaration instance C Int a => D Char [a].] > can't. But it's hard to formulate a general rule. > -fallow-undecidable-instances simply says that you, the programmer, take > responsibility for termination. Witho

[Haskell] Excessive sharing and GHC

Questions prompted by the "Excessive Sharing" section, page 405, of SPJ's "The Implementation of Functional Programming". This section gives 2 variations of a power list function, semantically equivalent, but with different space behaviours. Paraphrasing, given a caller of "length (powerListXX

[Haskell] ANNOUNCE: JRegex library

JRegex is a library that provides interfaces to both PCRE (perl comptatable regular expressions) and Posix regular expressions. it also provides an operator (=~) which is similar, but much more powerful than the perl operator. In addition, the syntax uses extensible type classes so you may extend