Send Beginners mailing list submissions to
[email protected]
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
[email protected]
You can reach the person managing the list at
[email protected]
When replying, please edit your Subject line so it is more specific
than "Re: Contents of Beginners digest..."
Today's Topics:
1. Re: Foldable for (,) (Michael Orlitzky)
2. Re: Foldable for (,) ([email protected])
----------------------------------------------------------------------
Message: 1
Date: Mon, 24 Apr 2017 06:44:59 -0400
From: Michael Orlitzky <[email protected]>
To: [email protected]
Subject: Re: [Haskell-beginners] Foldable for (,)
Message-ID: <[email protected]>
Content-Type: text/plain; charset=utf-8; format=flowed
On 04/24/2017 02:52 AM, Jonathon Delgado wrote:
>
> Michael Orlitzky - everything in .NET has to descend from Object
> because of it's OO design. Why does tuple have to implement Foldable
> if it doesn't provide any useful functions?
>
That was sarcasm =P
I agree with you.
------------------------------
Message: 2
Date: Mon, 24 Apr 2017 07:34:34 -0500
From: [email protected]
To: The Haskell-Beginners Mailing List - Discussion of primarily
beginner-level topics related to Haskell <[email protected]>
Subject: Re: [Haskell-beginners] Foldable for (,)
Message-ID: <[email protected]>
Content-Type: text/plain; charset=utf-8
> El 24 abr 2017, a las 03:20, David Thomas <[email protected]> escribió:
>
> One thing that's been missed in this discussion is that constraints
> can propagate.
>
> Of course no one is wanting to pass something they know is a tuple
> into a function they know is length. But a function that expects
> something Foldable might want to know length or sum, and it might be
> reasonable to call that function on a tuple.
>
Do you have a real-world example of a case where that's useful, and difficult
to achieve in another (non-Foldable) way?
Genuinely asking, so that when we talk about what's gained/lost we have
something concrete to talk about.
Tom
> On Sun, Apr 23, 2017 at 11:52 PM, Jonathon Delgado
> <[email protected]> wrote:
>> Tony Morris - please could you give a (practical) example of code where the
>> a tuple could realistically be passed to length, but you don't know what the
>> answer will be at compile time?
>>
>> Michael Orlitzky - everything in .NET has to descend from Object because of
>> it's OO design. Why does tuple have to implement Foldable if it doesn't
>> provide any useful functions?
>>
>> Thank you very much everyone in this thread for helping me understand!
>> _______________________________________________
>> Beginners mailing list
>> [email protected]
>> http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners
> _______________________________________________
> Beginners mailing list
> [email protected]
> http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners
------------------------------
Subject: Digest Footer
_______________________________________________
Beginners mailing list
[email protected]
http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners
------------------------------
End of Beginners Digest, Vol 106, Issue 18
******************************************
