From: erik quanstrom <quanstro@quanstro.net>
To: 9fans@cse.psu.edu
Subject: Re: [9fans] How to move to rc from sh/bash
Date: Sun, 10 Feb 2008 12:47:56 -0500 [thread overview]
Message-ID: <f2a5c42bf76c887240e8ec236169825b@quanstro.net> (raw)
In-Reply-To: <41F23396-1019-4C8E-A65A-E42824B0E23B@mac.com>
> It produces the string ' bla$e''o' in rc syntax. The one thing I like
> about two quoting styles in the Bourne shell is that I can use
it's not so much the number of quotes (there are three, by the way),
it's the complex rules. for example:
; /bin/bash
$ x=1
$ echo "$x"
1
$ echo '$x'
$x
$ echo `echo "\$x"`
1 <- reparsing rule.
$ echo "'$x'"
'1'
$ echo "'\$x'"
'$x'
but
$ echo `echo
> The proper is
>
> if [ $bla -eq $otherbla ]; then
> :
> fi
>
> The advantage of rc is that that : is not necessary!
>
> Oh, and let's not forget what happens when bla or otherbla is nil! In
> rc,
> if (~ $bla $otherbla) { }
> is all that is needed - no hooks.
that's actually a problem. while ~ is nice, it only does shell matching.
what if you want regexp matching or test (aka on unix [) operators?
then you have exactly the same problem with missing variables.
> And what I dislike:
> - >[2=] is not the same as >[2]/dev/null (some programs crash with
> the former
this isn't a shell issue. >[2=] closes fd 2. it's not clear to me that
arbitrary plan 9 programs are expected to run without one of the
three fds they've been promised by convention.
- erik
next prev parent reply other threads:[~2008-02-10 17:47 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-02-09 7:53 Hongzheng Wang
2008-02-09 8:01 ` mattmobile
2008-02-09 8:41 ` Hongzheng Wang
2008-02-09 8:57 ` mattmobile
2008-02-09 9:00 ` erik quanstrom
2008-02-09 9:21 ` Hongzheng Wang
2008-02-09 10:11 ` Charles Forsyth
2008-02-09 10:27 ` Lluís Batlle
2008-02-09 15:06 ` Uriel
2008-02-09 17:54 ` Charles Forsyth
2008-02-09 21:59 ` geoff
2008-02-09 13:00 ` Anthony Sorace
2008-02-10 16:59 ` Gorka Guardiola
2008-02-10 17:16 ` Pietro Gagliardi
2008-02-10 17:47 ` erik quanstrom [this message]
2008-02-10 18:12 ` Martin Neubauer
2008-02-11 15:04 ` erik quanstrom
2008-02-11 23:03 ` Martin Neubauer
2008-02-11 23:25 ` Pietro Gagliardi
2008-02-20 15:04 ` maht
2008-02-20 15:08 ` Federico G. Benavento
2008-02-20 15:24 ` erik quanstrom
2008-02-20 15:55 ` maht
2008-02-11 23:59 ` Uriel
2008-02-12 11:57 ` Martin Neubauer
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=f2a5c42bf76c887240e8ec236169825b@quanstro.net \
--to=quanstro@quanstro.net \
--cc=9fans@cse.psu.edu \
/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 NNTP newsgroup(s).