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Re: `append' vs. `nconc'
From: |
Barry Margolin |
Subject: |
Re: `append' vs. `nconc' |
Date: |
Thu, 31 Dec 2015 21:53:17 -0500 |
User-agent: |
MT-NewsWatcher/3.5.3b3 (Intel Mac OS X) |
In article <mailman.1440.1451588113.843.help-gnu-emacs@gnu.org>,
Emanuel Berg <embe8573@student.uu.se> wrote:
> <tomas@tuxteam.de> writes:
>
> > - it's very obvious It's a local value you are
> > keeping in your little scope. (One might argue that
> > then, it's an idiomatic way to emphasize this fact
> > to the (human) reader...)
>
> The thing here is, when it is very obvious and
> everything is small and easy to handle, what is the
> actual gain in time and space not using `append'?
>
> Answer:
>
> -> 0
>
> But OK, as a matter of principle it can be a cool
> thing to know/do.
NCONC was created at least 40 years ago, when computers were slow and
had very little memory (a modern cellphone is has the power of a roomful
of 70's-era mainframes). And garbage collection was also very slow
(generational GC hadn't been developed yet).
So optimizations like NCONC could be very useful back then. These days,
the benefit is probably very little.
--
Barry Margolin, barmar@alum.mit.edu
Arlington, MA
*** PLEASE post questions in newsgroups, not directly to me ***
- Re: `append' vs. `nconc', (continued)
- Re: `append' vs. `nconc', Emanuel Berg, 2015/12/30
- Message not available
- Re: `append' vs. `nconc', Pascal J. Bourguignon, 2015/12/31
- Re: `append' vs. `nconc', Emanuel Berg, 2015/12/31
- Re: `append' vs. `nconc', tomas, 2015/12/31
- side effects, list sharing [was: `append' vs. `nconc'], Drew Adams, 2015/12/31
- Re: side effects, list sharing [was: `append' vs. `nconc'], Emanuel Berg, 2015/12/31
- RE: side effects, list sharing [was: `append' vs. `nconc'], Drew Adams, 2015/12/31
- Re: `append' vs. `nconc', Emanuel Berg, 2015/12/31
- Message not available
- Re: `append' vs. `nconc',
Barry Margolin <=
- Message not available
- Re: `append' vs. `nconc', Pascal J. Bourguignon, 2015/12/31
- Message not available
- Re: `append' vs. `nconc', Teemu Likonen, 2015/12/31
- Re: `append' vs. `nconc', Emanuel Berg, 2015/12/31
- Re: `append' vs. `nconc', Teemu Likonen, 2015/12/31
- Message not available
- Re: `append' vs. `nconc', Pascal J. Bourguignon, 2015/12/30