Send Beginners mailing list submissions to
beginners@haskell.org
To subscribe or unsubscribe via the World Wide Web, visit
http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners
or, via email, send a message with subject or body 'help' to
beginners-requ...@haskell.org
You can reach the person managing the list at
beginners-ow...@haskell.org
When replying, please edit your Subject line so it is more specific
than "Re: Contents of Beginners digest..."
Today's Topics:
1. can I use "pure" all the time instead of "return" now?
(Doug McIlroy)
2. Re: can I use "pure" all the time instead of "return" now?
(Silent Leaf)
3. Re: can I use "pure" all the time instead of "return" now?
(Silent Leaf)
4. Re: can I use "pure" all the time instead of "return" now?
(Silent Leaf)
5. Re: can I use "pure" all the time instead of "return" now?
(Iustin Pop)
6. Re: can I use "pure" all the time instead of "return" now?
(Imants Cekusins)
----------------------------------------------------------------------
Message: 1
Date: Sun, 15 May 2016 10:29:34 -0400
From: Doug McIlroy <d...@cs.dartmouth.edu>
To: beginners@haskell.org
Subject: [Haskell-beginners] can I use "pure" all the time instead of
"return" now?
Message-ID: <201605151429.u4fetyu5023...@coolidge.cs.dartmouth.edu>
Content-Type: text/plain; charset=us-ascii
> the name [return] "stains" the functional semantics in Monadic code,
> in my opinion
Amusing. For me, the term "pure" stains monads as impure or diluted.
The moral overtones of "pure", as in "purely functional language",
drive out more benign interpretatations such as "unadorned". Not
a felicitous coinage.
Doug McIlroy
------------------------------
Message: 2
Date: Sun, 15 May 2016 17:08:43 +0200
From: Silent Leaf <silent.le...@gmail.com>
To: The Haskell-Beginners Mailing List - Discussion of primarily
beginner-level topics related to Haskell <beginners@haskell.org>
Subject: Re: [Haskell-beginners] can I use "pure" all the time instead
of "return" now?
Message-ID:
<cagfccjod6rgmkc9pxkxp_dutfawttsmmmcdoxb4+72+18a-...@mail.gmail.com>
Content-Type: text/plain; charset="utf-8"
that's great news! Thanks to all your answers :)
Hope the "no return" proposal gets accepted and incorporated!
Le dimanche 15 mai 2016, Marcin Mrotek <marcin.jan.mro...@gmail.com> a
?crit :
> Hello,
>
>> If/when Applicative Do drops, would using 'return' force monad semantics
on a do-block that could otherwise be
>> applicative? That's the only thing that comes to mind. Otherwise yeah,
I've been using 'pure' exclusively for a while.
>
> I think so, at least until the "Monad of no return" proposal
> (https://ghc.haskell.org/trac/ghc/wiki/Proposal/MonadOfNoReturn)
> lands.
>
> Best regards,
> Marcin Mrotek
> _______________________________________________
> Beginners mailing list
> Beginners@haskell.org
> http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL:
<http://mail.haskell.org/pipermail/beginners/attachments/20160515/e5f3fcf1/attachment-0001.html>
------------------------------
Message: 3
Date: Sun, 15 May 2016 17:37:28 +0200
From: Silent Leaf <silent.le...@gmail.com>
To: The Haskell-Beginners Mailing List - Discussion of primarily
beginner-level topics related to Haskell <beginners@haskell.org>
Subject: Re: [Haskell-beginners] can I use "pure" all the time instead
of "return" now?
Message-ID:
<CAGFccjO=y5swflo9aave-b5h5iapdstjoe3wd+so0dzajho...@mail.gmail.com>
Content-Type: text/plain; charset="utf-8"
Interesting interpretation!
It might not be the one intended, but I always saw "pure" as meaning
something like "input just wrapped" (echoing Maybe ofc), "input without
effects", i think is the terminology. In other terms, to me "pure", there,
is not an absolute description of the "type" of input (especially since the
name of a function traditionally mostly defines the output, not the input),
as in "non-monadic values are impure", but is a relative description
visavis the input, aka, "the output is the undiluted, uneffectful monadic
version of the input". Dunno if that was what you meant by "unadorned".
In other terms "pure" makes me see the function as a sort of identity that
does not dilute or otherwise modify the input value, solely "wraps" it
(more or less metaphorically), makes it monadic without modification. I
don't see it as meaning that its input values are of a purer "kind" than
the corresponding outputs because those latter are (more) monadic. And we
can feed monadic values to pure anyway.
As for echoing "purely functional language", well ... i don't really see
the link (but i might very well miss something), but at any rate isn't it
true in the first place (Haskell being pure, barring uses of
unsafeStuff/Foreign/etc)?
Le dimanche 15 mai 2016, Doug McIlroy <d...@cs.dartmouth.edu> a ?crit :
>
>> the name [return] "stains" the functional semantics in Monadic code,
>> in my opinion
>
> Amusing. For me, the term "pure" stains monads as impure or diluted.
> The moral overtones of "pure", as in "purely functional language",
> drive out more benign interpretatations such as "unadorned". Not
> a felicitous coinage.
>
> Doug McIlroy
> _______________________________________________
> Beginners mailing list
> Beginners@haskell.org
> http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL:
<http://mail.haskell.org/pipermail/beginners/attachments/20160515/6aab49e8/attachment-0001.html>
------------------------------
Message: 4
Date: Sun, 15 May 2016 17:39:39 +0200
From: Silent Leaf <silent.le...@gmail.com>
To: The Haskell-Beginners Mailing List - Discussion of primarily
beginner-level topics related to Haskell <beginners@haskell.org>
Subject: Re: [Haskell-beginners] can I use "pure" all the time instead
of "return" now?
Message-ID:
<cagfccjm5my7caun0t+30sudp6unif5d1mizh8g+gvdrjrck...@mail.gmail.com>
Content-Type: text/plain; charset="utf-8"
Typo, I wrote:
> as in "non-monadic values are impure"
meant of course
> as in "monadic values are impure"
Le dimanche 15 mai 2016, Silent Leaf <silent.le...@gmail.com> a ?crit :
> Interesting interpretation!
> It might not be the one intended, but I always saw "pure" as meaning
something like "input just wrapped" (echoing Maybe ofc), "input without
effects", i think is the terminology. In other terms, to me "pure", there,
is not an absolute description of the "type" of input (especially since the
name of a function traditionally mostly defines the output, not the input),
as in "non-monadic values are impure", but is a relative description
visavis the input, aka, "the output is the undiluted, uneffectful monadic
version of the input". Dunno if that was what you meant by "unadorned".
> In other terms "pure" makes me see the function as a sort of identity
that does not dilute or otherwise modify the input value, solely "wraps" it
(more or less metaphorically), makes it monadic without modification. I
don't see it as meaning that its input values are of a purer "kind" than
the corresponding outputs because those latter are (more) monadic. And we
can feed monadic values to pure anyway.
>
> As for echoing "purely functional language", well ... i don't really see
the link (but i might very well miss something), but at any rate isn't it
true in the first place (Haskell being pure, barring uses of
unsafeStuff/Foreign/etc)?
>
> Le dimanche 15 mai 2016, Doug McIlroy <d...@cs.dartmouth.edu> a ?crit :
>>
>>> the name [return] "stains" the functional semantics in Monadic code,
>>> in my opinion
>>
>> Amusing. For me, the term "pure" stains monads as impure or diluted.
>> The moral overtones of "pure", as in "purely functional language",
>> drive out more benign interpretatations such as "unadorned". Not
>> a felicitous coinage.
>>
>> Doug McIlroy
>> _______________________________________________
>> Beginners mailing list
>> Beginners@haskell.org
>> http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners
>>
-------------- next part --------------
An HTML attachment was scrubbed...
URL:
<http://mail.haskell.org/pipermail/beginners/attachments/20160515/38a0d480/attachment-0001.html>
------------------------------
Message: 5
Date: Sun, 15 May 2016 23:17:58 +0200
From: Iustin Pop <ius...@k1024.org>
To: The Haskell-Beginners Mailing List - Discussion of primarily
beginner-level topics related to Haskell <beginners@haskell.org>
Subject: Re: [Haskell-beginners] can I use "pure" all the time instead
of "return" now?
Message-ID: <20160515211758.gc17...@teal.hq.k1024.org>
Content-Type: text/plain; charset=us-ascii
On 2016-05-15 10:29:34, Doug McIlroy wrote:
>
> > the name [return] "stains" the functional semantics in Monadic code,
> > in my opinion
>
> Amusing. For me, the term "pure" stains monads as impure or diluted.
> The moral overtones of "pure", as in "purely functional language",
> drive out more benign interpretatations such as "unadorned". Not
> a felicitous coinage.
That only happens if we give moral values to such technical terms. And
probably happens more often to native English speakers; for me, it's
much easier to separate Applicative pure from other meanings of pure.
Interesting :)
regards,
iustin
------------------------------
Message: 6
Date: Mon, 16 May 2016 00:32:46 +0200
From: Imants Cekusins <ima...@gmail.com>
To: The Haskell-Beginners Mailing List - Discussion of primarily
beginner-level topics related to Haskell <beginners@haskell.org>
Subject: Re: [Haskell-beginners] can I use "pure" all the time instead
of "return" now?
Message-ID:
<cap1qinzgnehtsqyteouc240ukenrrs5h9h2sre7ffwcs_v+...@mail.gmail.com>
Content-Type: text/plain; charset="utf-8"
why not use (%%) as alias for both pure and return?
% - as in "investment return"
% - as in "pure distilled .. "
:-P
?
-------------- next part --------------
An HTML attachment was scrubbed...
URL:
<http://mail.haskell.org/pipermail/beginners/attachments/20160516/02c0d8ef/attachment.html>
------------------------------
Subject: Digest Footer
_______________________________________________
Beginners mailing list
Beginners@haskell.org
http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners
------------------------------
End of Beginners Digest, Vol 95, Issue 21
*****************************************
