From: Per Bothner <per@bothner.com>
To: kawa@sourceware.org
Subject: Re: behavior of CASE with strings PART 2
Date: Thu, 19 Jan 2017 04:53:00 -0000 [thread overview]
Message-ID: <7b059bf7-e537-1338-de60-6a6a93baaae8@bothner.com> (raw)
In-Reply-To: <e778b9c7-fe7a-1d1a-7c73-8723906e2454@bothner.com>
On 01/17/2017 10:36 PM, Per Bothner wrote:
> I think this is something to think of for the Kawa 3.0 release,
> using the new PATTERN construct in each clause.
The invoke branch has a 'match' form, which has the syntax:
(match TARGET-EXPR (PATTERN BODY...) ...)
This matches TARGET-EXPR against each PATTERN, until one matches,
at which point the BODY... forms are evaluated.
This is the 'match' form from Racket:
https://docs.racket-lang.org/guide/match.html
https://docs.racket-lang.org/reference/match.html
Unfortunately, the implemented forms of PATTERN are very
limited, but the intention to allow literals and quoted forms.
These will be compared using equal?, so you will be able to write:
(match "yes"
("no" #f)
("yes" #t))
THIS IS NOT YET IMPLEMENTED. (It's not conceptually hard; I just need to
decide the best way to present such match forms.)
I think this is the generalization of 'case' that we're looking for.
--
--Per Bothner
per@bothner.com http://per.bothner.com/
next prev parent reply other threads:[~2017-01-19 4:53 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-01-17 10:07 Damien MATTEI
2017-01-17 13:24 ` Per Bothner
2017-01-17 15:57 ` Jamison Hope
2017-01-18 6:37 ` Per Bothner
2017-01-19 4:53 ` Per Bothner [this message]
2017-01-19 10:04 ` Damien MATTEI
2017-01-19 16:00 ` Per Bothner
2017-01-21 9:47 ` Damien Mattei
2017-01-22 4:36 ` match form as a generalization of case Per Bothner
2017-01-23 22:12 ` Damien Mattei
2017-01-23 22:27 ` Per Bothner
2017-01-20 22:54 behavior of CASE with strings PART 2 Damien Mattei
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
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=7b059bf7-e537-1338-de60-6a6a93baaae8@bothner.com \
--to=per@bothner.com \
--cc=kawa@sourceware.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.
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).