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Date: Tue, 13 Sep 2016 20:41:44 +0000
From: Daniel Shahaf <danielsh@apache.org>
To: Cedric Blancher <cedric.blancher@gmail.com>
Cc: twilight <pipfstarrd@openmailbox.org>, freebsd-hackers@freebsd.org
Subject: Re: What is the point in expression: !!var ?
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Cedric Blancher wrote on Tue, Sep 13, 2016 at 22:10:24 +0200:
> The point is to transform the value of a (any kind, like pointer) to a
> Boolean value.

In more words: «!!x» is equivalent to «(x ? 1 : 0)».

Daniel