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Today's Topics:
1. Re: Beginner question. (brad73435 Smith)
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Message: 1
Date: Tue, 12 Sep 2023 06:35:14 -0700
From: brad73435 Smith <[email protected]>
To: The Haskell-Beginners Mailing List - Discussion of primarily
beginner-level topics related to Haskell <[email protected]>
Subject: Re: [Haskell-beginners] Beginner question.
Message-ID: <[email protected]>
Content-Type: text/plain; charset=utf-8
That’s an impressive step in complexity!
FWIW, for ‘f x y = x <> " " <> y’ that website gave the same result as the
book… ‘f = (<>) . (<> " ")’… so it seems to do a good job of giving a
simplified solution.
Understood re only using point-free for simple, clear cases… though it was a
good exercise for me to understand what’s going on with the function
composition operator (.).
Thank you!
Brad
Sent from my iPhone
> On Sep 12, 2023, at 1:08 AM, Sylvain Henry <[email protected]> wrote:
>
> Hi,
>
> https://pointfree.io/ gives:
>
> Input: f x y z = x <> " " <> y <> " " <> z
>
> Output: f = ((<>) .) . flip flip " " . ((<>) .) . (<>) . (<> " ")
>
> So no, it's not something simple!
>
> For clarity I would recommend using the non-point-free version, even in the
> case given in the book. Use point-free only in simple cases like `map (+ 1)`
> where the meaning is obvious.
>
> Sylvain
>
>
>> On 12/09/2023 02:45, Brad Smith wrote:
>> I just started working my way through a Haskell book... first time with
>> functional programming. Mid way through the first chapter she's introducing
>> point-free programming with a trivial example transitioning from not
>> point-free...
>>
>> makeGreeting salutation person = salutation <> " " <> person
>>
>> to point free...
>>
>> makeGreeting' = (<>) . (<> " ")
>>
>> After a little playing with it... it seems to make sense. So I thought I'd
>> try evolving from salutation and name to salutation, first, and last names.
>> But, after a bit of tinkering, I haven't been able to make it work...
>>
>> I'm sure it's something simple (one way or the other)... any help would be
>> appreciated!
>>
>> Brad
>>
>> _______________________________________________
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