G'day all.
Quoting Janis Voigtlaender <[EMAIL PROTECTED]>:
> I find the omission of quantifications in the produced theorems
> problematic.
I agree. Indeed, if you look at the source code, the quantifications
_are_ generated, they're just not printed. The reason is that the
output was (re-)des
I'd like to see a mix of the two systems. Top level quantifiers
should be optional; they often don't improve readability.
-- Lennart
On Sep 4, 2006, at 04:21 , Janis Voigtlaender wrote:
[EMAIL PROTECTED] wrote:
G'day all.
Quoting Donald Bruce Stewart <[EMAIL PROTECTED]>:
Get some
[EMAIL PROTECTED] wrote:
G'day all.
Quoting Donald Bruce Stewart <[EMAIL PROTECTED]>:
Get some free theorems:
lambdabot> free f :: (b -> b) -> [b] -> [b]
f . g = h . f => map f . f g = f h . map f
I finally got around to fixing the name clash bug. It now reports:
g . h = k . g
G'day all.
Quoting Donald Bruce Stewart <[EMAIL PROTECTED]>:
> Get some free theorems:
> lambdabot> free f :: (b -> b) -> [b] -> [b]
> f . g = h . f => map f . f g = f h . map f
I finally got around to fixing the name clash bug. It now reports:
g . h = k . g => map g . f h = f k .
Hello Udo,
Friday, September 1, 2006, 10:14:44 PM, you wrote:
> The general process is called "lambda elimination" and can be done
> mechanically. Ask Goole for "Unlambda", the not-quite-serious
> programming language; since it's missing the lambda,
afaik, FP proposed by Backus was serious lamb
haskell:
> Julien Oster wrote:
>
> >But I'm having problems with one of the functions:
> >
> >func3 f l = l ++ map f l
>
> While we're at it: The best thing I could come up for
>
> func2 f g l = filter f (map g l)
>
> is
>
> func2p f g = (filter f) . (map g)
>
> Which isn't exactly point-_fre
haskell:
> Hello,
>
> I was just doing Exercise 7.1 of Hal Daum?'s very good "Yet Another
> Haskell Tutorial". It consists of 5 short functions which are to be
> converted into point-free style (if possible).
>
> It's insightful and after some thinking I've been able to come up with
> solution
Julien Oster wrote:
> = ((.) (filter f)) . map g l
> = (.)((.) . filter f)(map) g l -- desugaring
> = (.map)((.) . filter f) g l -- sweeten up
> = (.map) . (.) . filter g l-- definition of (.)
By the way, I think from now on, when doing point-free-ify
Udo Stenzel wrote:
Thank you all a lot for helping me, it's amazing how quickly I received
these detailed answers!
> func2 f g l = filter f (map g l)
> func2 f g = (filter f) . (map g) -- definition of (.)
> func2 f g = ((.) (filter f)) (map g) -- desugaring
> func2 f = ((.) (filter f)) . m
Julien Oster wrote:
> While we're at it: The best thing I could come up for
>
> func2 f g l = filter f (map g l)
>
> is
>
> func2p f g = (filter f) . (map g)
>
> Which isn't exactly point-_free_. Is it possible to reduce that further?
Sure it is:
func2 f g l = filter f (map g l)
func2 f g = (
On Friday 01 September 2006 11:44, Neil Mitchell wrote:
> Hi
>
> > func2 f g l = filter f (map g l)
> > is
> > func2p f g = (filter f) . (map g)
>
> func2 = (. map) . (.) . filter
>
> Again, how anyone can come up with a solution like this, is entirely
> beyond me...
To answer part of the OP's que
Hi
func2 f g l = filter f (map g l)
is
func2p f g = (filter f) . (map g)
func2 = (. map) . (.) . filter
Again, how anyone can come up with a solution like this, is entirely
beyond me...
Thanks
Neil
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Hi Julien,
func3 f l = l ++ map f l
func3 f = ap (++) (map f)
func3 = ap (++) . map
Looks pretty clear and simple. However, I can't come up with a solution.
Is it even possible to remove one of the variables, f or l? If so, how?
I have no idea how to do this - the solution is to log into #ha
Julien Oster wrote:
But I'm having problems with one of the functions:
func3 f l = l ++ map f l
While we're at it: The best thing I could come up for
func2 f g l = filter f (map g l)
is
func2p f g = (filter f) . (map g)
Which isn't exactly point-_free_. Is it possible to reduce that furth
Hello,
I was just doing Exercise 7.1 of Hal Daumé's very good "Yet Another
Haskell Tutorial". It consists of 5 short functions which are to be
converted into point-free style (if possible).
It's insightful and after some thinking I've been able to come up with
solutions that make me understa
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