RE: [PHP-DEV] Re: [PHP-LANG] Approaching the First Draft [of a language spec]

On Tue, 21 Nov 2000, Zeev Suraski wrote:

> I agree that the spec shouldn't document weird odds and ends that are
> either bugs or misfeatures that we decide that should be fixed as a part of
> the language (although it'd be a good thing to document these until they're
> fixed).  I just think that as a general rule, describing what exists,
> rather than what *should* exist, is the way to go (there can be some
> distance between the actual implementation and the spec, due to
> bugs/misfeatures, but the distance should be very short).

    We will need to discuss the behaviour of the conditional
    operator. That issue has been touched multiple times in the
    past. I think this stage warrants reevaluating the facts
    though as we will define the behaviour once and for all.

    Fixing the behaviour of this operator will only affect
    constructs which have a certain degree of complexity. I.e.

        $cond = $foo ? $bar : $baz ? $john : $doe;

    It will not affect constructs with less complexity.

    A user who is capable of understanding and writing such
    complex constructs will notice that PHP's semantics don't
    reflect the standard behaviour of the operator.

    Therefore, the construct will be re-written as

        $cond = $foo ? $bar : ($baz ? $john : $doe);

    Hence, I'm arguing that a user

        (a) who is capable of deploying such constructs, and
        (b) understanding the effects

    will already have applied the proper work-around as layed out
    above.

    And thus, changing the semantics of the conditional
    operator will not affect backwards compatibility of existing
    scripts in a negative manner. Indeed, it will correct scripts
    which have been written in the assumption of
    right-associativity of the operator.

    This implies that there is no valid use of the current
    behaviour. I challenge everyone to come up with an example
    where the left-associativity of the operator is indeed
    useful.

    - Sascha