From: Kevin Ryde <user42@zip.com.au>
To: 6596@debbugs.gnu.org
Subject: bug#6596: 23.2; cl.texi docs loop destructuring for alist
Date: Sat, 10 Jul 2010 09:44:21 +1000 [thread overview]
Message-ID: <87r5jci5ka.fsf@blah.blah> (raw)
[-- Attachment #1: Type: text/plain, Size: 361 bytes --]
I didn't immediately realize the cl `loop' macro destructuring could be
used to crunch an alist. Perhaps an example in the manual per below.
If you're not a cl programmer you need lots of examples to understand
that huge `loop' thing :-).
2010-07-10 Kevin Ryde <user42@zip.com.au>
* cl.texi (For Clauses): Add destructuring example processing an
alist.
[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #2: cl.texi.loop-alist.diff --]
[-- Type: text/x-diff, Size: 676 bytes --]
--- cl.texi.orig 2010-07-10 09:37:14.000000000 +1000
+++ cl.texi 2010-07-10 09:38:54.000000000 +1000
@@ -2599,7 +2599,14 @@
than values the trailing variables get the value @code{nil}.
If @code{nil} is used as a variable name, the corresponding
values are ignored. Destructuring may be nested, and dotted
-lists of variables like @code{(x . y)} are allowed.
+lists of variables like @code{(x . y)} are allowed, so for example
+to process an alist
+
+@example
+(loop for (key . value) in '((a . 1) (b . 2))
+ collect value)
+ @result{} (1 2)
+@end example
@node Iteration Clauses, Accumulation Clauses, For Clauses, Loop Facility
@subsection Iteration Clauses
[-- Attachment #3: Type: text/plain, Size: 1053 bytes --]
In GNU Emacs 23.2.1 (i486-pc-linux-gnu, GTK+ Version 2.20.0)
of 2010-05-16 on raven, modified by Debian
configured using `configure '--build' 'i486-linux-gnu' '--build' 'i486-linux-gnu' '--prefix=/usr' '--sharedstatedir=/var/lib' '--libexecdir=/usr/lib' '--localstatedir=/var/lib' '--infodir=/usr/share/info' '--mandir=/usr/share/man' '--with-pop=yes' '--enable-locallisppath=/etc/emacs23:/etc/emacs:/usr/local/share/emacs/23.2/site-lisp:/usr/local/share/emacs/site-lisp:/usr/share/emacs/23.2/site-lisp:/usr/share/emacs/site-lisp:/usr/share/emacs/23.2/leim' '--with-x=yes' '--with-x-toolkit=gtk' '--with-toolkit-scroll-bars' 'build_alias=i486-linux-gnu' 'CFLAGS=-DDEBIAN -g -O2' 'LDFLAGS=-g' 'CPPFLAGS=''
Important settings:
value of $LC_ALL: nil
value of $LC_COLLATE: nil
value of $LC_CTYPE: nil
value of $LC_MESSAGES: nil
value of $LC_MONETARY: nil
value of $LC_NUMERIC: nil
value of $LC_TIME: nil
value of $LANG: en_AU
value of $XMODIFIERS: nil
locale-coding-system: iso-latin-1-unix
default enable-multibyte-characters: t
next reply other threads:[~2010-07-09 23:44 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-07-09 23:44 Kevin Ryde [this message]
2010-07-11 2:13 ` bug#6596: 23.2; cl.texi docs loop destructuring for alist Glenn Morris
2010-07-13 1:50 ` Kevin Ryde
2010-07-13 15:49 ` Glenn Morris
2010-07-16 1:19 ` Kevin Ryde
2010-07-16 16:12 ` Glenn Morris
2010-07-21 15:21 ` Stefan Monnier
2010-07-23 0:51 ` Kevin Ryde
2010-07-23 3:47 ` Dan Nicolaescu
2011-07-14 0:15 ` Lars Magne Ingebrigtsen
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/emacs/
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=87r5jci5ka.fsf@blah.blah \
--to=user42@zip.com.au \
--cc=6596@debbugs.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/emacs.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).