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Subject: Re: [PHP-DEV] Implicit isset/isempty check on short-ternary operator
From: mail_ben_schmidt@yahoo.com.au (Ben Schmidt)

> I cry whenever I see code with @ in it...

I don't like @ either. The whole point of this proposal though is to
offer a safe alternative, a way to suppress only those notices which are
being accounted for by the programmer and no more, without messing
around making a custom error handler that ignores one type of error,
which is the current way to do it 'safely'.

> What we're wanting are existential assignment and ternary operators.
> Simply put, a painless way to set or use a default value based on the
> existence of a variable without needing a bunch of extra code to avoid
> notices/errors. Sorry Ben, but I think extending the @ operator to
> prevent errors from being generated in the first place is a terrible
> idea. I would prefer to see @ removed from PHP if possible.

I never meant to extend @, I meant simply to reuse that symbol--i.e. the
@ character--as part of the syntax of a new safer feature, since it
performed a similar function. The actual @ operator is not changed in
any way. Rather, a new @[...] array indexing mechanism is added which
suppresses the Undefined Index notice, and only that notice, by not
generating it.

> I would also want this to work with objects and scalars. It would be
> particularly useful within view scripts where the values are passed in
> via extract, or as object properties, and you can't instantiate them
> first because that would clear them.

I guess that's a vaguely valid use case, though I still somewhat think
it is the responsibility of the caller of the view script to ensure all
variables are instantiated (to null if appropriate). I guess an
unambiguous syntax for this could be $@variable.

I guess object properties are another case. I wonder how common. I guess
$object@->property would be the way to deal with that.

I still lean towards just offering it for arrays, though. That seems to be
the area of greatest need by a significant margin.

Ben.