From: Mikael Magnusson <mikachu@gmail.com>
To: Bart Schaefer <schaefer@brasslantern.com>
Cc: Zsh hackers list <zsh-workers@zsh.org>
Subject: Re: Up-scope named references, vs. ksh
Date: Tue, 5 Mar 2024 06:43:02 +0100 [thread overview]
Message-ID: <CAHYJk3TF_OmfjQmnTgayA7zmCh1gVVGtDbhkvbLvs83R84C+hg@mail.gmail.com> (raw)
In-Reply-To: <CAH+w=7Y9e+H3Ga+b87TeQgZgzgjj+QhkTQ9FiZyz6cAPq+BQtw@mail.gmail.com>
On 3/5/24, Bart Schaefer <schaefer@brasslantern.com> wrote:
> On Mon, Mar 4, 2024 at 5:05 PM Oliver Kiddle <opk@zsh.org> wrote:
>>
>> Isn't defaulting to a scalar type fairly normal.
>
> Sure, but Stephane wants a global that's a blank slate for anything to
> be assigned to. I don't think we have a way to do that -- the way the
> implementation works in the absence of namerefs is to actually
> remove/free the parameter and create a new one. If there are locals
> pointing to the global via pm->old, and the global gets removed, all
> the locals are also destroyed.
>
>> A different problem I'm finding is with not being able to hide the
>> reference type of a variable in a called function:
>
> That's actually "correct" -- from the doc:
>
> When a _named reference_ is created with 'typeset -n', all uses of PNAME
> in assignments and expansions instead assign to or expand RNAME. This
> also applies to 'unset PNAME' and to most subsequent uses of 'typeset'
> with the exception of 'typeset -n' and 'typeset +n'
>
> I admit this is a little weird when the named reference is inherited
> from another scope. The most recent FAQ entry that I patched actually
> suggests using "private -n var" to prevent downward scope leakage of
> namerefs.
Is this possible to change? I feel like if "typeset myvar" (or "local
myvar") cannot be depended on to create a local parameter, a lot of
code will no longer be safe that previously was (in the sense that it
doesn't break if calling code / the shell environmnet has certain
parameters defined). Surely we cannot expect everyone to add +n to
every single "local" statement? If the current behavior is wanted, one
can always use typeset -g to get it, presumably? And that would be
more backward compatible, right?
Like say I have typeset -n foo=PS1 in my .zshrc because I don't like
writing $PS1 manually, now any code I call which has a "local foo" is
broken, which is not great. They have explicitly added their "local
foo" to be able to use the name 'foo' regardless of the calling
environment... "private -n foo" works in this case too, but I still
hold my opinion.
--
Mikael Magnusson
next prev parent reply other threads:[~2024-03-05 5:44 UTC|newest]
Thread overview: 48+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-02-06 2:21 [PATCH 1/3]: Add named references Bart Schaefer
2023-02-08 3:45 ` Oliver Kiddle
2023-02-08 4:59 ` Bart Schaefer
2023-02-08 23:16 ` Bart Schaefer
2023-02-09 0:47 ` Oliver Kiddle
2023-02-09 2:01 ` Oliver Kiddle
2023-02-09 5:45 ` Bart Schaefer
2023-02-09 4:49 ` Bart Schaefer
2023-02-09 20:49 ` Oliver Kiddle
2023-02-09 23:07 ` Bart Schaefer
2023-02-11 3:04 ` Bart Schaefer
2023-02-11 3:55 ` Bart Schaefer
2023-02-11 5:36 ` Speaking of dangerous referents Bart Schaefer
2023-02-12 8:00 ` Oliver Kiddle
2023-02-12 8:34 ` Bart Schaefer
2023-02-11 7:02 ` [PATCH 1/3]: Add named references Oliver Kiddle
2023-02-11 7:45 ` Bart Schaefer
2023-02-11 23:43 ` Bart Schaefer
2023-02-11 23:45 ` Bart Schaefer
2023-02-12 7:38 ` Oliver Kiddle
2024-02-11 7:00 ` Stephane Chazelas
2024-02-11 16:14 ` Bart Schaefer
2024-02-11 16:42 ` Bart Schaefer
2024-02-18 3:26 ` Up-scope named references, vs. ksh Bart Schaefer
2024-02-20 21:05 ` Stephane Chazelas
2024-02-20 22:30 ` Bart Schaefer
2024-02-21 20:12 ` Stephane Chazelas
2024-02-29 5:16 ` Bart Schaefer
2024-03-01 18:22 ` Stephane Chazelas
2024-03-01 20:34 ` Bart Schaefer
2024-03-02 7:29 ` Bart Schaefer
2024-03-02 23:55 ` [PATCH] "typeset -nu" (was Re: Up-scope named references, vs. ksh) Bart Schaefer
2024-03-01 23:28 ` Up-scope named references, vs. ksh Bart Schaefer
2024-03-03 13:44 ` Stephane Chazelas
2024-03-03 19:04 ` Bart Schaefer
2024-03-03 20:27 ` Stephane Chazelas
2024-03-03 22:58 ` Bart Schaefer
2024-03-04 19:59 ` Stephane Chazelas
2024-03-05 1:05 ` Oliver Kiddle
2024-03-05 2:53 ` Bart Schaefer
2024-03-05 5:43 ` Mikael Magnusson [this message]
2024-03-05 6:30 ` Stephane Chazelas
2024-03-06 5:04 ` [PATCH] local vs. nameref scoping (was Re: Up-scope named references, vs. ksh) Bart Schaefer
2023-02-12 9:02 ` [PATCH 1/3]: Add named references Oliver Kiddle
2023-02-12 18:59 ` Bart Schaefer
2023-02-12 19:45 ` PM_* flags in zsh.h (was Re: [PATCH 1/3]: Add named references) Bart Schaefer
2023-02-12 21:01 ` Oliver Kiddle
2023-02-12 22:54 ` [PATCH 1/3]: Add named references Oliver Kiddle
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=CAHYJk3TF_OmfjQmnTgayA7zmCh1gVVGtDbhkvbLvs83R84C+hg@mail.gmail.com \
--to=mikachu@gmail.com \
--cc=schaefer@brasslantern.com \
--cc=zsh-workers@zsh.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.vuxu.org/mirror/zsh/
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).