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Date: Tue, 24 Jul 2012 18:18:06 +0200
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To: Galen Wright-Watson <ww.galen@gmail.com>
Cc: internals@lists.php.net
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Subject: Re: [PHP-DEV] Implicit isset in ternary operator
From: alex.aulbach@gmail.com (Alex Aulbach)

2012/7/24 Galen Wright-Watson <ww.galen@gmail.com>:
>> Don't see much difference between
>>
>> $a = $b ?: $c;
>>
>> and (for example I used "i" for "if")
>>
>> $a = _i($b, $c);
>
>
> When $b is defined, there isn't much appreciable difference. However, this
> behavior already exists, so there isn't much to debate. In the cases under
> discussion, a userland function can't suppress undefined variable & index
> notices, so it isn't a viable substitution.

Hm, you're right. I normaly don't do such ugly things. :)

Hum. This behaviour is needed in very special contexts. In my eyes
only when printing out/filling up the templates etc. Under normal
circumstances I think, you should program without too much operators,
because a deflation of operators leads to - hm - deflation of the
language. Thats the same, as if everybody can create new words: after
a short time, nobody can understand anybody.

Hmmmm. But we can make this to a principle in this very, very closed context.

So: What about if we can create new operators inside PHP with PHP? I
think not more than 36 operators are needed at any time in a project.
So we can do this:

set_operator_handler('i', function ($b, $c) {
        if (empty($b)) return $b;
        return $b;
}, OPERATOR_HANDLE_UNSET_WITHOUT_WARNINGS)

then we can do this:

$a = $a ?i: $b;

This should help for this case and could be a great things for those
very special cases, when you need the same operation over and over.

Comments
----------------

Context: I think those operators should be global.

Security: Hm. Could operators be overwritten? How to test, if an
operator already exists? I think it should work like including a file.
E. g. set_operator_handler_once() should be possible, so that a second
call isn't executed.

Other things: I don't like the first operator (the operator-name). Any
goof idea?


-- 
Alex Aulbach