Re: [RFC] Partial Function Application, take 2

On Thu, Jun 10, 2021, at 3:17 AM, Guilliam Xavier wrote: > On Wed, Jun 2, 2021 at 7:47 PM Larry Garfield <larry@garfieldtech.com> > wrote: > > > Hi folks. After much off-list discussion, iteration, and consideration, > > we have a new draft of PFA ready for review. > > > > The URL is the same: > > > > https://wiki.php.net/rfc/partial_function_application > > > > Hi, thanks all for the reworks! I just thought to something: does it > support nullsafe calls, e.g. $foo?->bar(?)? and if yes, what > is the > signature of the Closure when $foo === null (and does it make a > difference if, inside a function, it was created as a local variable `$foo > = null; vs received as a typed parameter ?Foo $foo`)? I just checked, and it... sort of supports nullsafe. Rather, if you try to partial a method on a null object, you get null back for your closure. Then when you try to call it, you get a "cannot invoke null" error. Which... I think makes sense. cf: https://3v4l.org/4XeB3/rfc#focus=rfc.partials As a cute side effect, Joe pointed out you could do this: https://3v4l.org/ERRdY/rfc#focus=rfc.partials I wouldn't really call that a feature, but more of a side effect of the implementation. Please don't count on that behavior. I also discovered while checking that nullsafe differentiates between null and undefined. That was unexpected, but not related to the topic at hand. :-) > Related, for $null === null, is $c = > $null->bar(?); / `$c = > $null::baz(?); an immediate error, or only later when calling > $c($arg)`? That dies with "call to member function on null" when trying to create the partial: https://3v4l.org/E6MgK/rfc#focus=rfc.partials --Larry Garfield