From: tomas@tuxteam.de
To: Zelphir Kaltstahl <zelphirkaltstahl@posteo.de>
Cc: guile-user@gnu.org
Subject: Re: Writing a procedure in different style
Date: Sun, 13 Dec 2020 16:43:00 +0100 [thread overview]
Message-ID: <20201213154300.GC6620@tuxteam.de> (raw)
In-Reply-To: <66a4948b-6c35-d9df-daa0-865956f52821@posteo.de>
[-- Attachment #1: Type: text/plain, Size: 1492 bytes --]
On Sun, Dec 13, 2020 at 04:01:24PM +0100, Zelphir Kaltstahl wrote:
> Hi Tomas!
>
> In some way what you write makes sense. Let me state here, that I did
> read that book and worked through it for a year though, even through the
> complicated parts like the y-combinator and some chapters I must have
> read like 4 or 5 times and discovered new aspects on each try.
That's it -- I'm through some n-th iteration and still go "oh!" from
time to time :-D
> What is typically the case in the book is a different situation though,
> than what was in Taylan's procedure. Usually it is the list you are
> working on in that iteration, which you check for being (null? ...), not
> the thing, that you give as argument to a recursive call or as a return
> value, which you add in some way to the result. Usually the questions
> from the quote are asked once the argument is received in the next
> iteration. That I definitely usually do, but in Taylan's answer there is
> an (if (null? ...) ...) for the `rest`, inside the case, where the usual
> (null? ...) check is already done on the subtree, which we recur on.
I have the hunch that this is only shifting things one level
up or down the stack, but basically, it's the same principle
at work. I'd have to fiddle for a while with that to see whether
I'm totally off, though.
Anyway, a reminder for me to do the n+1st iteration: "Do It, Do
It Again, and Again, and Again, ..." :-)
Thanks for that!
Cheers
- t
[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 198 bytes --]
next prev parent reply other threads:[~2020-12-13 15:43 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-12-12 12:22 Writing a procedure in different style Zelphir Kaltstahl
2020-12-13 7:06 ` Taylan Kammer
2020-12-13 11:51 ` Taylan Kammer
2020-12-13 12:29 ` Zelphir Kaltstahl
2020-12-13 14:24 ` tomas
2020-12-13 15:01 ` Zelphir Kaltstahl
2020-12-13 15:43 ` tomas [this message]
2020-12-20 17:57 ` Zelphir Kaltstahl
2020-12-21 12:31 ` tomas
2020-12-21 21:29 ` Zelphir Kaltstahl
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
List information: https://www.gnu.org/software/guile/
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20201213154300.GC6620@tuxteam.de \
--to=tomas@tuxteam.de \
--cc=guile-user@gnu.org \
--cc=zelphirkaltstahl@posteo.de \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).