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Date: Thu, 9 Aug 2012 17:58:04 +0200
Message-ID: <CAF+90c9DvXYPoBoNaqFteHvEGO8V3kfS_AZH3OJ7MxXnie6S0w@mail.gmail.com>
To: Andrew Faulds <ajf@ajf.me>
Cc: Stas Malyshev <smalyshev@sugarcrm.com>, PHP internals <internals@lists.php.net>
Content-Type: text/plain; charset=ISO-8859-1
Subject: Re: [PHP-DEV] Generators in PHP
From: nikita.ppv@gmail.com (Nikita Popov)

On Wed, Aug 8, 2012 at 10:55 PM, Andrew Faulds <ajf@ajf.me> wrote:
> Hmm. This is just a quick thought:
>
> Considering the yield syntax will vary about needing () round it, why not
> make it a "fake" function (language construct).
>
> This way it's consistent: yield(), yield($v), yield($k => $v), $a = yield(),
> etc.
>
> (yield $x) is just messy as an expression. We don't have (isset $x), we have
> isset($x).

There are two reasons why I would not choose that syntax:

1. This would make "yield" look like a functions, without actually
being a function. PHP has done this in the past quite often and I
think it was a mistake. It is the reason why people try to write
empty(someCall()). It looks like a function, so they expect it to
behave like one. Similarly you also can't do $f = 'empty'; $f($foo),
which again is confusing to people new to the language.

2. Other languages that implement generators also use the "yield $foo"
syntax (and also have the same parentheses requirements). So this
makes PHP consistent with them.

Nikita