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To: Zsh hackers list <zsh-workers@zsh.org>
From: Martijn Dekker <martijn@inlv.org>
Subject: $((++a++))
Message-ID: <74d2c8e3-7a0f-b705-29c8-e5a2f6e182aa@inlv.org>
Date: Mon, 4 Sep 2017 22:45:46 +0200
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Why is this accepted?

% a=1
% echo $((++a++))
2
% echo $((--a--))
1

Looks like that should be an invalid arithmetic expression.

- M.