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From: Yuri Khan <yuri.v.khan@gmail.com>
To: help-gnu-emacs@gnu.org
Subject: Re: Why is `pop' not named `npop'?
Date: Wed, 17 Jan 2024 18:13:11 +0700	[thread overview]
Message-ID: <CAP_d_8W2RRgQyEKZXqTztqU0RrjBcbiYYDR2b=md5dmmQyfVZA@mail.gmail.com> (raw)
In-Reply-To: <87ply0n2qj.fsf@dataswamp.org>

On Wed, 17 Jan 2024 at 17:53, Emanuel Berg <incal@dataswamp.org> wrote:

> >> the `pop' macro is destructive. Why isn't it called `npop'
> >> then? [...]

> > but there is also no need for a non-destructive pop since we
> > already have car.
>
> But shouldn't `pop' be called "ncar" then?

The ‘n’ in ‘nreverse’ and other destructive functions is said to mean
‘non-consing’, that is, they won’t allocate new cons cells but rather
modify what is already there to achieve the desired structure. The
focus is not on destructiveness, it is on the lack of pressure on the
allocator.

‘car’ is already as non-consing as it gets.



      reply	other threads:[~2024-01-17 11:13 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-01-16  4:28 Why is `pop' not named `npop'? mbork
2024-01-16  5:07 ` Po Lu
2024-01-16  6:25 ` Philip Kaludercic
2024-01-17  1:54   ` Emanuel Berg
2024-01-17 11:13     ` Yuri Khan [this message]

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