From mboxrd@z Thu Jan  1 00:00:00 1970
X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on inbox.vuxu.org
X-Spam-Level: 
X-Spam-Status: No, score=0.2 required=5.0 tests=DKIM_SIGNED,DKIM_VALID,
	DKIM_VALID_AU,FREEMAIL_FROM,MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE,
	RCVD_IN_MSPIKE_H2,RDNS_NONE,UNPARSEABLE_RELAY autolearn=no
	autolearn_force=no version=3.4.4
Received: from authenticated user by zero.zsh.org with local 
	id 1kikgb-000OMI-NS; Fri, 27 Nov 2020 20:49:45 +0000
Authentication-Results: zsh.org;
	iprev=pass (mail-wr1-f48.google.com) smtp.remote-ip=209.85.221.48;
	dkim=pass header.d=gmail.com header.s=20161025 header.a=rsa-sha256;
	dmarc=pass header.from=gmail.com;
	arc=none
Received: from mail-wr1-f48.google.com ([209.85.221.48]:42294)
	by zero.zsh.org with esmtps (TLS1.3:TLS_AES_128_GCM_SHA256:128)
	id 1kikgL-000O7Y-JB; Fri, 27 Nov 2020 20:49:30 +0000
Received: by mail-wr1-f48.google.com with SMTP id l1so6818645wrb.9
        for <zsh-workers@zsh.org>; Fri, 27 Nov 2020 12:49:29 -0800 (PST)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
        d=gmail.com; s=20161025;
        h=mime-version:references:in-reply-to:from:date:message-id:subject:to
         :cc:content-transfer-encoding;
        bh=IHA9ftREZCtsmJ4VC+9OgScgj8XGkgOFPWoLrvcdNVU=;
        b=F1kR6ukM1xWYA32mmcbmQ9LZ+NFO1JgMtKXS8CPZUV0lva6G+d8MiysdK3rRnRRQp+
         z2Xd5nZZ1B3Fsxg2mC/v9Y3pkuaNAeVFS46FCEgR2fyseHJo9k3dn2/qBidUJ+oi4o4I
         hqI4jFA8aXB9fTt/5GLOgImYC9CaYV7vYFj6AnmNaO/B026bcsLbUnutl5JCR9KqnE3D
         WsuJAF5sfwAFkjhVxeMxCXpyPlZxEKK+r3vnnArtMTlKx0cZKINIy9se/2JSkoQNo5eo
         V+1QcrN5mm9qlS/ky0iZrvWFAt6eVexQIvhZlp9G7AGrzdwJQ+SQvZib8ivKNrPPYRqD
         T9bg==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
        d=1e100.net; s=20161025;
        h=x-gm-message-state:mime-version:references:in-reply-to:from:date
         :message-id:subject:to:cc:content-transfer-encoding;
        bh=IHA9ftREZCtsmJ4VC+9OgScgj8XGkgOFPWoLrvcdNVU=;
        b=OTA6csLSmETfFst/uxVbHG0Jp+cu0KhbagviG73dRBSom9lYiddt63k/lPYw7i9mxk
         C+vZm00QL0eh9hGRjlEl4exTVNM3qfCKGnR01UwZti9KC5llxnyif6M1bTKCSM0rrB0P
         NOQKpAMQo+BBV+VNOxoxAMgMkIwgqQ4fmOPneM7QKeWUK89fZzj01ueE90XNC6jGct56
         6xAaISdBp8A1lGfbYHzmaZHMInyan2yOGt4ndSCBvZKAAXGTXnUCIq0N4YXI2uF4PuF/
         VbzzLnUrRYvY22SoqyTwsQdV4nohwRavk9qYBpCq4bZCTOnoOrVnSdilZfbDL3Gd1tWO
         +hkQ==
X-Gm-Message-State: AOAM532GF9QbaYTKQSX6jay5/I8SKzvgp1F37c/YX3mTyTk/7nH+Ebnb
	uYpC5d23lvGauT8CGwzuo5xQfvJE8KkLjfFa+cWjwqrw6ixjAw==
X-Google-Smtp-Source: ABdhPJz9Jm8Y6zY1SoSMsRzcqgAI4tBjIkQlTwEnN94QVxFlWrpg08RB3QYGfc3GiJ4WxRyoSfTKhPtmMrJJuhJLpf4=
X-Received: by 2002:a5d:474f:: with SMTP id o15mr13252513wrs.100.1606510169240;
 Fri, 27 Nov 2020 12:49:29 -0800 (PST)
MIME-Version: 1.0
References: <CAN=4vMqr-MBuzikqkSJEnY5=hW6xjv_TcW_paZV9oKEXnDsmrw@mail.gmail.com>
 <CAMP44s0sU0B1fQq=BEJV+jp_jtjxpFbz6K=wqNpukLK4i31P4g@mail.gmail.com>
 <CAH+w=7a3vOa2+YXpOS0eCGTr_TGNe1uhPBu+B1Xb_4OmmhJk1A@mail.gmail.com>
 <CAMP44s2LRtJLMc-RWX6_o7qO_cshfcuWL0-NtrWfqYp9o7HcEA@mail.gmail.com>
 <CAH+w=7YZQA=vhA=-jVzYLvP_XmrN6f5Ra8TH5LsMrza8GVsKvQ@mail.gmail.com>
 <CAMP44s1m3zNAeZ9Gn3XcG0pHeavD9K_eXOjZz3LGoUvdpzucVA@mail.gmail.com>
 <CAH+w=7bhs3BVrBMjbcxPhrxh0fXMKeBVooNknLts+4QxHQYOZA@mail.gmail.com>
 <CAMP44s0QMzJuMPoMZ1BR=+Y2_n4iEE-coXVtmFTdaHj4AuxTVw@mail.gmail.com>
 <CAH+w=7Z+Brh5KfwUJakoaKfQ39WQbYoRELyfpu3YO1Ro-Ewvfg@mail.gmail.com>
 <CAMP44s1RLs-ASYFyvjvj7eGta5_WnsXSH_8jAXf-Zufk569E1Q@mail.gmail.com> <20201127154439.GC26720@tarpaulin.shahaf.local2>
In-Reply-To: <20201127154439.GC26720@tarpaulin.shahaf.local2>
From: Felipe Contreras <felipe.contreras@gmail.com>
Date: Fri, 27 Nov 2020 14:49:17 -0600
Message-ID: <CAMP44s2mkpWF-2coUW6u-9W03puSDdhSoF_HNdVbSqohpxvLkQ@mail.gmail.com>
Subject: Re: Bug with unset variables
To: Daniel Shahaf <d.s@daniel.shahaf.name>
Cc: Bart Schaefer <schaefer@brasslantern.com>, Zsh hackers list <zsh-workers@zsh.org>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
X-Seq: 47673
Archived-At: <https://zsh.org/workers/47673>
X-Loop: zsh-workers@zsh.org
Errors-To: zsh-workers-owner@zsh.org
Precedence: list
Precedence: bulk
Sender: zsh-workers-request@zsh.org
X-no-archive: yes
List-Id: <zsh-workers.zsh.org>
List-Help: <mailto:sympa@zsh.org?subject=help>
List-Subscribe: <mailto:sympa@zsh.org?subject=subscribe%20zsh-workers>
List-Unsubscribe: <mailto:sympa@zsh.org?subject=unsubscribe%20zsh-workers>
List-Post: <mailto:zsh-workers@zsh.org>
List-Owner: <mailto:zsh-workers-request@zsh.org>
List-Archive: <http://www.zsh.org/sympa/arc/zsh-workers>
Archived-At: <http://www.zsh.org/sympa/arcsearch_id/zsh-workers/2020-11/CAMP44s2mkpWF-2coUW6u-9W03puSDdhSoF_HNdVbSqohpxvLkQ%40mail.gmail.com>

On Fri, Nov 27, 2020 at 9:44 AM Daniel Shahaf <d.s@daniel.shahaf.name> wrot=
e:
>
> Felipe Contreras wrote on Wed, Nov 25, 2020 at 02:46:40 -0600:
> > Maybe there's a better way to describe this fact. Maybe Git's notion
> > of logically separate changes [1] helps (e.g. you should not mix
> > whitespace cleanups with functional changes). But the fact is that in
> > virtually all languages (and bash and ksh) there's an idiom to declare
> > a local variable and *only* declare a local variable (not do anything
> > else).
> >
> > Can we at least agree on that? In zsh typeset does *two* things.
>
> I'd rather say that =C2=ABtypeset=C2=BB does one thing =E2=80=94 it ${ver=
b}s a variable
> (for some value of $verb) =E2=80=94 and the zsh data model doesn't featur=
e
> a "Not really a value" value, so the variable necessarily gets _some_
> value, like =C2=ABint foo;=C2=BB in C.

If it's really one thing, then why does adding it in the example above
changes the behavior in *two* ways?

  func () {
    [[ -n "$1" ]] && var=3D$1
    dosomething ${var-other}
  }

  func () {
    typeset var
    [[ -n "$1" ]] && var=3D$1
    dosomething ${var-other}
  }

--=20
Felipe Contreras