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Today's Topics:
1. Re: Foldable for (,) (Michael Orlitzky)
2. Re: Foldable for (,) (amin...@gmail.com)
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Message: 1
Date: Mon, 24 Apr 2017 06:44:59 -0400
From: Michael Orlitzky <mich...@orlitzky.com>
To: beginners@haskell.org
Subject: Re: [Haskell-beginners] Foldable for (,)
Message-ID: <c59722bb-f6e6-0521-fbb9-8a0235e5d...@orlitzky.com>
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: amin...@gmail.com
To: The Haskell-Beginners Mailing List - Discussion of primarily
beginner-level topics related to Haskell <beginners@haskell.org>
Subject: Re: [Haskell-beginners] Foldable for (,)
Message-ID: <482a29c5-3474-464e-8e4e-4e6041d87...@gmail.com>
Content-Type: text/plain; charset=utf-8
> El 24 abr 2017, a las 03:20, David Thomas <davidleotho...@gmail.com> 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
> <volderm...@hotmail.com> 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!
>> _______________________________________________
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