Newsgroups: php.internals
Path: news.php.net
Xref: news.php.net php.internals:59693
Mailing-List: contact internals-help@lists.php.net; run by ezmlm
Received-SPF: pass (pb1.pair.com: domain gmail.com designates 209.85.212.42 as permitted sender)
References: <CAF+90c_hj7PrWbm42dj0DhN7Ygmc=vckP=bcYfsVuod4=RrOQQ@mail.gmail.com>
In-Reply-To: <CAF+90c_hj7PrWbm42dj0DhN7Ygmc=vckP=bcYfsVuod4=RrOQQ@mail.gmail.com>
Mime-Version: 1.0 (1.0)
Date: Wed, 11 Apr 2012 08:25:26 +0800
Message-ID: <2853275242330628205@unknownmsgid>
To: Nikita Popov <nikita.ppv@googlemail.com>
Cc: PHP internals <internals@lists.php.net>
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: quoted-printable
Subject: Re: [PHP-DEV] Allow non-variable arguments to empty()
From: laruence@gmail.com (Xinchen Hui)

Sent from my iPad

=E5=9C=A8 2012-4-11=EF=BC=8C6:54=EF=BC=8CNikita Popov <nikita.ppv@googlemai=
l.com> =E5=86=99=E9=81=93=EF=BC=9A

> Hey internals!
>
> Currently the empty() language construct only works on variables. You
> can write if (empty($array)) but not empty if (empty(getSomeArray()).
>
> The original reason for this restriction probably is that - in a way -
> it "doesn't make sense" to pass anything but a variable to empty() as
> you could just use the ! operator in this case. if
> (empty(getSomeArray())) is logically equivalent to if
> (!getSomeArray()).
>
> I'd like to propose to change empty() to accept arbitrary expressions.
>
> The reason is simple: Even though it is possible to write if
> (!getSomeArray()) with the same effect, if (empty(getSomeArray()))
> reads much nicer. !getSomeArray() to me somehow implies that
> getSomeArray() may return a bool(false) or something like that. On the
> other hand empty(getSomeArray()) seems naturally fit for checking for
> empty arrays.
+1 for this, but what about is set? They shou be consistent, :)

Thanks
>
> Another reason is that currently you get a very obscure error message
> if you try to use empty() on a function return value: "Can't use
> function return value in write context". Aha. Where did I try to write
> to the return value?!
>
> So, what do you think?
>
> Nikita
>
> PS: The patch is trivial: https://gist.github.com/2355274
>
> --
> PHP Internals - PHP Runtime Development Mailing List
> To unsubscribe, visit: http://www.php.net/unsub.php
>