Hi Rob On Tue, Jun 25, 2024 at 9:05 AM Rob Landers <rob@bottled.codes> wrote: > > On Tue, Jun 25, 2024, at 01:20, Ilija Tovilo wrote: > > On Mon, Jun 24, 2024 at 9:54 PM Robert Landers <landers.rob...@gmail.com> > wrote: > > > > To be honest, this is one of the smaller concerns I have with the new > > syntax. There might be some misunderstanding here, though. A > > non-existent key is NULL, always has been, and always will be. > > This is just not accurate. Inexistent indexes are not null in PHP, > they are undefined. PHP implicitly coerces undefined to null, because > undefined is not a value accessible to users. The same occurs when > accessing $undefinedVariable. For arrays, this fact is observable > through `foreach`, warnings when accessing the index, and likely > others. > > This is a bit like telling someone who fell off a ladder that they didn’t > “technically” fall, instead the Earth and them pulled at each other until > they collided and the ground + body absorbed the energy. > > While yes, you are “technically” correct, what you describe is essentially > unobservable from the context of the running code (unless you turn the > warning into an error/exception). For all direct accesses of array values > ($arr['key']) an array is infinitely full of nulls (I have actually depended > on this property at one point for a bloom filter).
If null array values were indeed unobservable, then [] would be === to [null] (or at least ==), and a foreach over [null] would result in 0 iterations. But neither of those are the case. > So yes, `[?'foo' => string]` and `['foo' => ?string]` are indeed > different. The former accepts `[]`, while the latter accepts `['foo' > => null]`. > > Are they actually different in practice though? That was my point. After the > “is” in both cases, you’ll have to use null-coalescence to retrieve the > value. For all intents, they are the same resulting code. If you can show a > difference in the resulting code and how it is an improvement, I may be > inclined to agree, but I can’t think of one. Sure. If a null value were to mean "not set", then ['foo' => string] should accept ['foo' => 'foo', 'bar' => null], which is absolutely observable if the code assumes it won't see any additional indexes. Ilija
