Re: [RFC] Property hooks, nee accessors

On Tue, May 9, 2023, at 5:46 PM, Larry Garfield wrote: >> I have a bigger concern: the take on references contradicts with the intro >> about BC breaks: turning a materialized property into virtual one would >> break BC as far as refs are concerned. One idea to fix that: add a ref >> hook, that must return a reference. If not implemented => Error when trying >> to get-by-ref. This could also help solve the $foo->array[] case (including >> the asym-visiblity issue). > > That might be possible. The issue there is that the returned ref would > still be bypassing the get/set hooks, so you're just adding a way to > dance around the existing hook implementations, which is exactly what > we're trying to avoid. Also, what would that hook even mean if used on > a virtual property? > > Moreover, in practice, getting a reference to a property is extremely > rare, with the exception of array writes. I cannot recall the last > time I even saw some code get a reference to a property. That's why we > felt comfortable just leaving it at is. In an earlier version of the > RFC we had a way for properties to just disable references without > adding any hooks, but removed it on the grounds that it was not worth > the effort. Addendum here: The RFC wasn't clear, in part because I wasn't clear, but the prohibition on [] on properties applies only on set. On get, whatever array value is returned from the hook is just a boring array, which can then be dereferenced to look up a key. I've updated the RFC accordingly to make it clearer what is and isn't allowed with arrays. --Larry Garfield