GNU bug report logs - #76413
[PATCH] New macro 'compf' for composing functions

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Message #32 received at 76413 <at> debbugs.gnu.org (full text, mbox):

From: Eshel Yaron <me <at> eshelyaron.com>
To: Stefan Kangas <stefankangas <at> gmail.com>
Cc: Stefan Monnier <monnier <at> iro.umontreal.ca>, 76413 <at> debbugs.gnu.org
Subject: Re: bug#76413: [PATCH] New macro 'compf' for composing functions
Date: Wed, 19 Feb 2025 20:00:14 +0100

Hi Stefan,

Stefan Kangas <stefankangas <at> gmail.com> writes:

> Eshel Yaron via "Bug reports for GNU Emacs, the Swiss army knife of text
> editors" <bug-gnu-emacs <at> gnu.org> writes:
>
>> Tags: patch
>>
>> This patch adds a new macro 'compf' that streamlines the common pattern
>> of function composition.
>>
>> Namely, instead of (lambda (x) (foo (bar (baz x)))), with this macro we
>> can write (compf foo bar baz), which expands to exactly the same form.
>
> Why not name it `compose` as in CL and ELisp?

It's a slightly different construct then Common Lisp's compose, so I
feel like calling it by that name could lead to wrong expectations.
Another option is fcomp instead of compf, BTW, if that seems better.

> How about a function with a compiler macro?

That's a valid alternative, but it'd require quoting function names,
which is slightly less concise/convenient.

Do you see a clear advantage for using a function in this case?


Thanks,

Eshel

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