On 3/15/07, Steve Downey [EMAIL PROTECTED] wrote:
EOk, i'm trying to write down, not another monad tutorial, because I
don't know that much yet, but an explication of my current
understanding of monads.
But before I write down something that is just flat worng, I thought
I'd get a cross check.
On 2/27/07, Henning Thielemann [EMAIL PROTECTED] wrote:
I suspect that someone has already done this: A Haskell library which
solves a system of simple equations, where it is only necessary to derive
a value from an equation where all but one variables are determined. Say
You might want to
On Jan 27, 2007, at 11:11 AM, Mark Wassell wrote:
Sometimes happy outputs 'parE' when I run it on my .y file? I
believe it is coming from a part of Grammer.lhs which has the
comment line
This bit is a real mess, mainly because of the error message
support.
Are there any suggestions on
On Jan 18, 2007, at 10:09 PM, Yitzchak Gale wrote:
I wrote:
Will (id :: A - A $!) do the trick?
Ulf Norell wrote:
The problem is not with id, it's with composition. For any f and g we
have
f . g = \x - f (g x)
So _|_ . g = \x - _|_ for any g.
OK, so then how about
f .! g = ((.) $! f
On Jan 19, 2007, at 1:06 PM, Yitzchak Gale wrote:
Hmm. I wrote:
for simplicity, we will ignore these distinctions
But do we really want to do that? Are the monads
that we use every day in Haskell really monads
if we check the axioms using (.!) instead of (.)
as we should? I'm not so sure
On Jan 16, 2007, at 7:22 PM, David House wrote:
Hey all,
I've written a chapter for the Wikibook that attempts to teach some
basic Category Theory in a Haskell hacker-friendly fashion.
http://en.wikibooks.org/wiki/Haskell/Category_theory
In the section on the category laws you say that the
On Dec 13, 2006, at 3:54 AM, Yitz Gale wrote:
Nice. Here is something similar:
reverseWords = concat . reverse . groupBy eqsp
where eqsp x y = isSpace x == isSpace y
This can be made even nicer using the 'on' function [1]:
reverseWords = concat . reverse . groupBy ((==) `on` isSpace)
On Oct 31, 2006, at 2:19 AM, Dimitrios Vytiniotis wrote:
-- Give a GADT for representation types
data R a where
Rint :: R Int
Rbool :: R Bool
Rpair :: R a - R b - R (a,b)
-- Give an existential type with a type representation
data TermEx where
MkTerm :: R a - Term a - TermEx
-- we
On Aug 17, 2006, at 10:18 AM, Szymon Ząbkiewicz wrote:
Hi.
When trying to compilke this code:
{...}
8.if (a == 0) (b == 0)
9. then do
10. nr1 - read (prompt enter 1. number: )
11. nr2 - read (prompt enter 2. number: )
12. else do
13.let nr1 =
