Re: lines/unlines and "inverse"

2002-07-22 Thread Lars Henrik Mathiesen
> From: Koen Claessen <[EMAIL PROTECTED]> > Date: Mon, 22 Jul 2002 11:25:16 +0200 (MET DST) > Lars Henrik Mathiesen wrote: > > | lines . unlines = id > | unlines . lines . unlines == unlines > | words . unwords . words = words > > Don't be fooled by

Re: gcd 0 0 = 0

2001-12-18 Thread Lars Henrik Mathiesen
> From: Marc van Dongen <[EMAIL PROTECTED]> > Date: Tue, 18 Dec 2001 09:32:49 + > > Alan Bawden ([EMAIL PROTECTED]) wrote: > : Indeed, that's a nice way of putting it. How about if the report just > : says: > : > :In order to make the non-negative integers into a lattice under `gcd' > :

Re: gcd 0 0 = 0

2001-12-17 Thread Lars Henrik Mathiesen
> From: Marc van Dongen <[EMAIL PROTECTED]> > Date: Sun, 16 Dec 2001 13:35:59 + > > Marc van Dongen ([EMAIL PROTECTED]) wrote: > > : An integer $a$ divides integer $b$ if there exists an integer > : $c$ such that $a c= b$. > > To make clear why $0$ (and not any other non-zero integer) i

Re: beginner's questions - fix f

2001-07-24 Thread Lars Henrik Mathiesen
> From: "Marcin 'Qrczak' Kowalczyk" <[EMAIL PROTECTED]> > Date: 24 Jul 2001 13:05:25 GMT > > 24 Jul 2001 12:04:33 -, Lars Henrik Mathiesen <[EMAIL PROTECTED]> pisze: > > > Now, anything that's defined as "x = f x" is call

Re: Haskell 98 Report possible errors, part one

2001-07-24 Thread Lars Henrik Mathiesen
> From: Dylan Thurston <[EMAIL PROTECTED]> > Date: Mon, 23 Jul 2001 19:57:54 -0400 > > On Mon, Jul 23, 2001 at 06:30:30AM -0700, Simon Peyton-Jones wrote: > > Someone else, quoted by Simon, attribution elided by Dylan, wrote: > > | 2.2. Identifiers can use small and large Unicode letters. > > |

Re: beginner's questions - fix f

2001-07-24 Thread Lars Henrik Mathiesen
> From: Bob Koutsky <[EMAIL PROTECTED]> > Date: Tue, 24 Jul 2001 09:49:33 +0200 > > [...] suddenly, I hit a wall: > > > Exercise 9.9: > remainder a b = if a < b then a > else remainder (a-b) b > > fix f = f (f

Re: Negatively recursive data types

2001-07-04 Thread Lars Henrik Mathiesen
> From: Keith Wansbrough <[EMAIL PROTECTED]> > Date: Wed, 04 Jul 2001 18:27:05 +0100 > > Hi... I'm currently looking at the semantics of recursive data types. > One thing that Haskell allows, but the semantics for it is very hairy, > is *negatively* recursive data types. That is, data types w

Re: newbie

2001-03-12 Thread Lars Henrik Mathiesen
> Date: Mon, 12 Mar 2001 17:16:29 +0100 > From: Frank Atanassow <[EMAIL PROTECTED]> > Lars Henrik Mathiesen wrote (on 10-03-01 20:35 -): > > However, in some expositions of category theory, the usefulness of > > monads is justified because they 'belong'

Re: newbie

2001-03-10 Thread Lars Henrik Mathiesen
> From: Joe English <[EMAIL PROTECTED]> > Date: Sat, 10 Mar 2001 09:34:28 -0800 > The relevant category for Haskell is the one in which > objects are types and arrows are functions. The identity > arrow for object 't' is 'id' instantiated at type 'id :: t -> t', > and composition of arrows is fu

Re: Knight Problem

2001-02-01 Thread Lars Henrik Mathiesen
> From: "Christoph M." <[EMAIL PROTECTED]> > Date: Fri, 2 Feb 2001 00:15:53 +0100 > Does anybody know how to solve the "Knight Problem" ? If you mean the Knight's Tour problem, the answer is yes. I coded up a version as an independent study back in grade 12 (1977) --- in COMAL on a Norsk Data m

Re: The importance and relevance of FP

2000-08-17 Thread Lars Henrik Mathiesen
> From: Ralf Muschall <[EMAIL PROTECTED]> > Date: 16 Aug 2000 21:46:44 +0200 > "Craig Dickson" <[EMAIL PROTECTED]> writes: > > simplistic, binary distinction), then you have to decide where to > > draw the line between "functional languages" and other languages > > that may, to some > > I think

Re: Two floating point questions

2000-06-12 Thread Lars Henrik Mathiesen
> Date: Mon, 12 Jun 2000 15:52:20 +0200 > From: Sven Panne <[EMAIL PROTECTED]> > Is the following behaviour of GHC allowed by the H98 report? > > -- Foo.hs > main :: IO () > main = print (0.1234567891234567891 :: Float, > 0.12345678912345678

Re: Overlapping instances?

1999-06-14 Thread Lars Henrik Mathiesen
> Date: Sun, 13 Jun 1999 16:46:57 -0400 > From: Kevin Atkinson <[EMAIL PROTECTED]> > Thanks but why is this OK? Sorry, I misunderstood the question. > class T f r > > instance T a (a) > instance T (c a b) (c a (b)) > I mean the comman instance here is T (c a b) (c a (b)). Well, i

Re: Overlapping instances?

1999-06-13 Thread Lars Henrik Mathiesen
> Date: Sun, 13 Jun 1999 01:51:06 -0400 > From: Kevin Atkinson <[EMAIL PROTECTED]> > Could some one explain to me why [this is not OK]: > class T f r > > instance T a (d a) > instance T (c a b) (c a (d b)) Because, just as Hugs says: > *** Common instance : T (a b c) (a b (a b c

Re: how to write a simple cat

1999-06-01 Thread Lars Henrik Mathiesen
> Date: Tue, 01 Jun 1999 17:32:22 +0200 > From: Sven Panne <[EMAIL PROTECTED]> > Don't fear! Mr. One-Liner comes to the rescue:;-) > >longerThan fn lenlim = readFile fn >>= lines .| filter (length .| (>lenlim)) .| >zip [1..] .| map (\(n,l) -> shows n ") " ++ l) .| unlines .| putStr Are