From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <zsh-users-return-22018-mason-zsh=primenet.com.au@zsh.org>
Received: (qmail 22948 invoked by alias); 21 Oct 2016 21:12:20 -0000
Mailing-List: contact zsh-users-help@zsh.org; run by ezmlm
Precedence: bulk
X-No-Archive: yes
List-Id: Zsh Users List <zsh-users.zsh.org>
List-Post: <mailto:zsh-users@zsh.org>
List-Help: <mailto:zsh-users-help@zsh.org>
X-Seq: 22018
Received: (qmail 668 invoked from network); 21 Oct 2016 21:12:20 -0000
X-Qmail-Scanner-Diagnostics: from forward4o.cmail.yandex.net by f.primenet.com.au (envelope-from <kp-pav@yandex.ru>, uid 7791) with qmail-scanner-2.11 
 (clamdscan: 0.99.2/21882. spamassassin: 3.4.1.  
 Clear:RC:0(37.9.109.248):SA:0(0.0/5.0):. 
 Processed in 0.731021 secs); 21 Oct 2016 21:12:20 -0000
X-Spam-Checker-Version: SpamAssassin 3.4.1 (2015-04-28) on f.primenet.com.au
X-Spam-Level: 
X-Spam-Status: No, score=0.0 required=5.0 tests=FREEMAIL_FROM,SPF_PASS,
	T_DKIM_INVALID autolearn=unavailable autolearn_force=no version=3.4.1
X-Envelope-From: kp-pav@yandex.ru
X-Qmail-Scanner-Mime-Attachments: |
X-Qmail-Scanner-Zip-Files: |
Received-SPF: pass (ns1.primenet.com.au: SPF record at _spf-ipv4.yandex.ru designates 37.9.109.248 as permitted sender)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yandex.ru; s=mail; t=1477083984;
	bh=1g/W8XRXGMpYCpRaM6HZIAZ3cw4ekFArqWIqIiHFyaA=;
	h=From:To:In-Reply-To:References:Subject:Message-Id:Date;
	b=jhS4XlF8WMig5kGqP0kbAvy2yDCRN8cXh4bE0JqFTxURySJjFxZqCQflNZ+HisRFy
	 O1+ShAQoskyoRgXKIfpMKkLaizzt0nNqYYWby0bQXSqDDs5qN2ZdyQ7atsX+GsZ+bD
	 hJHesb/hTe6qDJICzipTKVpkGUgfYaecj70cekH0=
Authentication-Results: mxback4h.mail.yandex.net; dkim=pass header.i=@yandex.ru
From: "Nikolay Aleksandrovich Pavlov (ZyX)" <kp-pav@yandex.ru>
To: Martijn Dekker <martijn@inlv.org>,
	"zsh-users@zsh.org" <zsh-users@zsh.org>
In-Reply-To: <032fd4ec-89c1-9dae-a729-c440048ff3ec@inlv.org>
References: <032fd4ec-89c1-9dae-a729-c440048ff3ec@inlv.org>
Subject: Re: Checking if a variable is exported
MIME-Version: 1.0
Message-Id: <4961661477083984@web22h.yandex.ru>
X-Mailer: Yamail [ http://yandex.ru ] 5.0
Date: Sat, 22 Oct 2016 00:06:24 +0300
Content-Transfer-Encoding: 7bit
Content-Type: text/plain

21.10.2016, 23:34, "Martijn Dekker" <martijn@inlv.org>:
> Hi all,
>
> Does zsh have a straightforward way for a script to check if a variable
> is exported? The closest-to-straightforward way I know of is to parse
> the output of 'typeset -p varname', which is hairy because the output
> might include various options to the command.
>
> Thanks,
>
> - M.

I guess shortest version is something like

    zmodload zsh/parameter
    is_exported() {
        (( !! ${${(s.-.)parameters[$1]}[(Ie)export]} ))
    }

or

    is_exported() {
        (( !! ${${(ts.-.)${(P)1}}[(Ie)export]} ))
    }

(do not remember when (t) modifier was introduced, but AFAIR it is younger then zsh/parameter module).

---

BTW, if I use

    () { echo ${(Pts.-.)1} } PATH

I get `scalar export special` like expected. But I always get return status 1 when using

    () { (( !! ${${(Pts.-.)1}[(Ie)export]} )) } PATH

: enclosing this thing into additional ${} like

    () { echo ${${(Pts.-.)1}} } PATH

makes zsh echo $PATH value and not `scalar export special` like expected. Removing additional ${} neither works:

    () { echo ${(Pts.-.)1[1]} } PATH

echoes `s` like if it was a space-separated string and not an array.