unofficial mirror of guix-devel@gnu.org 
 help / color / mirror / code / Atom feed
From: "Ludovic Courtès" <ludo@gnu.org>
To: Attila Lendvai <attila@lendvai.name>
Cc: guix-devel <guix-devel@gnu.org>
Subject: Re: using an SRFI that is not available in Guile
Date: Mon, 24 Jan 2022 16:41:30 +0100	[thread overview]
Message-ID: <87ilu9rvit.fsf@gnu.org> (raw)
In-Reply-To: <g5Tu3m82fFtEGxcAEVElyT3s5H4jp-quL72OSkeDPP4MTxXwNLB8k2HMa9OHM5O4uKQsJ0ZsWvDGxzePeOdaH-VJ-pa9mooe4U2uRVA71wo=@lendvai.name> (Attila Lendvai's message of "Fri, 21 Jan 2022 13:59:10 +0000")

Hi,

Attila Lendvai <attila@lendvai.name> skribis:

>> Out of curiosity, in what case do you need to represent “unset fields”?
>
>
> i think an example works better here: consider Swarm, a p2p storage
> solution. its node implementation is called Bee. bees can join
> swarms. there are some well-known swarms: 'testnet' and 'mainnet'.
>
> when someone specifies the swarm field as a symbol naming one of the
> well-known swarms, then some other mandatory fields should default to
> the appropriate values derived from it, *and* the service should warn
> if those fields are also set by the user.
>
> and when one is joining a custom swarm, as per giving a string name in
> the swarm field, then the service should warn when these mandatory
> fields are not explicitly specified.

I see.  The ‘define-configuration’ macro uses 'disabled as a way to
indicate fields that have not been user-specified.  Would that be of any
help in this context?

Another approach would be to use ‘define-record-type*’ and record all
the default values, including those derived from other fields (just like
the default ‘home-directory’ field of <user-account> is derived from
‘name’.)

Does that make sense?

Ludo’.


  reply	other threads:[~2022-01-24 15:41 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-01-12 16:46 using an SRFI that is not available in Guile Attila Lendvai
2022-01-12 17:01 ` Attila Lendvai
2022-01-12 17:09 ` Maxime Devos
2022-01-13  9:55   ` Attila Lendvai
2022-01-13 10:49     ` Maxime Devos
2022-01-13 18:20       ` Attila Lendvai
2022-01-13 20:48         ` Attila Lendvai
2022-01-14 12:02         ` Maxime Devos
2022-01-17 13:45           ` Attila Lendvai
2022-01-13 10:53     ` Maxime Devos
2022-01-13 10:56       ` Maxime Devos
2022-01-18 15:09 ` Ludovic Courtès
2022-01-18 17:06   ` Attila Lendvai
2022-01-19 10:34     ` Ludovic Courtès
2022-01-21 13:59       ` Attila Lendvai
2022-01-24 15:41         ` Ludovic Courtès [this message]
2022-01-24 23:02           ` Attila Lendvai
2022-02-05 11:13             ` Ludovic Courtès

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://guix.gnu.org/

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=87ilu9rvit.fsf@gnu.org \
    --to=ludo@gnu.org \
    --cc=attila@lendvai.name \
    --cc=guix-devel@gnu.org \
    /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.
Code repositories for project(s) associated with this public inbox

	https://git.savannah.gnu.org/cgit/guix.git

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).