Re: [Haskell-cafe] Reply-To: Header in Mailinglists (was: About Fun with type functions example)
Hi Bastian,
I generally observe the pattern that non-technical mailing lists tend to
set this header to help the user, while technical mailing list assume
(rightfully, IMHO) that the readers are fine without Reply-To. The
reasons against setting that I recall at the moment are:
* Mails meant to be send privately but accidentally sent to the list
are worse than mails meant to be public but sent privately.
* Users who send to the list with a Reply-To header set do not want
that header to be lost.
* With some clients, the Reply-To-All feature does not always work as
expected when there is a Reply-To-Header.
Most clients have a Reply-To-List feature (Evolution on Ctrl-L) that
works fine, once you get used to it.
Greetings,
Joachim
Am Freitag, den 19.11.2010, 04:55 +0100 schrieb Bastian Erdnüß:
Hi there,
I just put an answer two this in beginn...@haskell.org. It was not on
purpose to move the topic. It's just that questions I feel I can
answer are usually beginner level questions and so I'm not often
writing in the cafe itself.
It would make my life a little bit more easy if the mailing lists on
haskell.org would add a Reply-To: header automatically to each message
containing the address of the mailing list, the message was sent to.
Usually that's the place where others would want to sent the answers
to, I would suppose.
Is there a reason that that's not the case? Am I missing something?
Or am I supposed to install a more cleaver mail client which can do
that for me? Is there one? Probably written in Haskell ;-)
Cheers,
Bastian
On Nov 19, 2010, at 1:07, Daniel Peebles wrote:
The best you can do with fromInt is something like Int - (forall n. (Nat n)
= n - r) - r, since the type isn't known at compile time.
On Thu, Nov 18, 2010 at 2:52 PM, Arnaud Bailly
arnaud.oq...@gmail.comwrote:
Thanks a lot, that works perfectly fine!
Did not know this one...
BTW, I would be interested in the fromInt too.
Arnaud
On Thu, Nov 18, 2010 at 8:22 PM, Erik Hesselink hessel...@gmail.com
wrote:
On Thu, Nov 18, 2010 at 20:17, Arnaud Bailly arnaud.oq...@gmail.com
wrote:
Hello,
I am trying to understand and use the Nat n type defined in the
aforementioned article. Unfortunately, the given code does not compile
properly:
[snip]
instance (Nat n) = Nat (Succ n) where
toInt _ = 1 + toInt (undefined :: n)
[snip]
And here is the error:
Naturals.hs:16:18:
Ambiguous type variable `n' in the constraint:
`Nat n' arising from a use of `toInt' at Naturals.hs:16:18-39
Probable fix: add a type signature that fixes these type variable(s)
You need to turn on the ScopedTypeVariables extension (using {-#
LANGUAGE ScopedTypeVariables #-} at the top of your file, or
-XScopedTypeVariables at the command line). Otherwise, the 'n' in the
class declaration and in the function definition are different, and
you want them to be the same 'n'.
Erik
--
Joachim nomeata Breitner
mail: m...@joachim-breitner.de | ICQ# 74513189 | GPG-Key: 4743206C
JID: nome...@joachim-breitner.de | http://www.joachim-breitner.de/
Debian Developer: nome...@debian.org
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Re: [Haskell-cafe] Reply-To: Header in Mailinglists (was: About Fun with type functions example)
Reply-to munging has come up many times on this list (and others).
See this page for information on why many people do not like Reply-to
munging:
http://marc.merlins.org/netrants/listreplyto.html
- jeremy
On Thu, Nov 18, 2010 at 9:55 PM, Bastian Erdnüß earth...@web.de wrote:
Hi there,
I just put an answer two this in beginn...@haskell.org. It was not on
purpose to move the topic. It's just that questions I feel I can answer are
usually beginner level questions and so I'm not often writing in the cafe
itself.
It would make my life a little bit more easy if the mailing lists on
haskell.org would add a Reply-To: header automatically to each message
containing the address of the mailing list, the message was sent to. Usually
that's the place where others would want to sent the answers to, I would
suppose.
Is there a reason that that's not the case? Am I missing something? Or am I
supposed to install a more cleaver mail client which can do that for me? Is
there one? Probably written in Haskell ;-)
Cheers,
Bastian
On Nov 19, 2010, at 1:07, Daniel Peebles wrote:
The best you can do with fromInt is something like Int - (forall n. (Nat n)
= n - r) - r, since the type isn't known at compile time.
On Thu, Nov 18, 2010 at 2:52 PM, Arnaud Bailly arnaud.oq...@gmail.comwrote:
Thanks a lot, that works perfectly fine!
Did not know this one...
BTW, I would be interested in the fromInt too.
Arnaud
On Thu, Nov 18, 2010 at 8:22 PM, Erik Hesselink hessel...@gmail.com
wrote:
On Thu, Nov 18, 2010 at 20:17, Arnaud Bailly arnaud.oq...@gmail.com
wrote:
Hello,
I am trying to understand and use the Nat n type defined in the
aforementioned article. Unfortunately, the given code does not compile
properly:
[snip]
instance (Nat n) = Nat (Succ n) where
toInt _ = 1 + toInt (undefined :: n)
[snip]
And here is the error:
Naturals.hs:16:18:
Ambiguous type variable `n' in the constraint:
`Nat n' arising from a use of `toInt' at Naturals.hs:16:18-39
Probable fix: add a type signature that fixes these type variable(s)
You need to turn on the ScopedTypeVariables extension (using {-#
LANGUAGE ScopedTypeVariables #-} at the top of your file, or
-XScopedTypeVariables at the command line). Otherwise, the 'n' in the
class declaration and in the function definition are different, and
you want them to be the same 'n'.
Erik
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[Haskell-cafe] Reply-To: Header in Mailinglists (was: About Fun with type functions example)
Hi there,
I just put an answer two this in beginn...@haskell.org. It was not on purpose
to move the topic. It's just that questions I feel I can answer are usually
beginner level questions and so I'm not often writing in the cafe itself.
It would make my life a little bit more easy if the mailing lists on
haskell.org would add a Reply-To: header automatically to each message
containing the address of the mailing list, the message was sent to. Usually
that's the place where others would want to sent the answers to, I would
suppose.
Is there a reason that that's not the case? Am I missing something? Or am I
supposed to install a more cleaver mail client which can do that for me? Is
there one? Probably written in Haskell ;-)
Cheers,
Bastian
On Nov 19, 2010, at 1:07, Daniel Peebles wrote:
The best you can do with fromInt is something like Int - (forall n. (Nat n)
= n - r) - r, since the type isn't known at compile time.
On Thu, Nov 18, 2010 at 2:52 PM, Arnaud Bailly arnaud.oq...@gmail.comwrote:
Thanks a lot, that works perfectly fine!
Did not know this one...
BTW, I would be interested in the fromInt too.
Arnaud
On Thu, Nov 18, 2010 at 8:22 PM, Erik Hesselink hessel...@gmail.com
wrote:
On Thu, Nov 18, 2010 at 20:17, Arnaud Bailly arnaud.oq...@gmail.com
wrote:
Hello,
I am trying to understand and use the Nat n type defined in the
aforementioned article. Unfortunately, the given code does not compile
properly:
[snip]
instance (Nat n) = Nat (Succ n) where
toInt _ = 1 + toInt (undefined :: n)
[snip]
And here is the error:
Naturals.hs:16:18:
Ambiguous type variable `n' in the constraint:
`Nat n' arising from a use of `toInt' at Naturals.hs:16:18-39
Probable fix: add a type signature that fixes these type variable(s)
You need to turn on the ScopedTypeVariables extension (using {-#
LANGUAGE ScopedTypeVariables #-} at the top of your file, or
-XScopedTypeVariables at the command line). Otherwise, the 'n' in the
class declaration and in the function definition are different, and
you want them to be the same 'n'.
Erik
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