Re: Consensus Gathering: is_initialized

On 27/05/2021 17:13, Andreas Leathley wrote:

How is "uninitialized" magic? It is a state of a class property in PHP that is currently being exposed via reflection

Apologies if my last message was a bit too hastily written, and may have come across as rude. What I meant by it being "magic" is that it can't be represented by any value or type. A lot of the examples in this thread attempt to use "uninitialized" like it was an extra value for the variable, as though the type of the property was "int|null|uninitialized". But that can't be declared in the property's type, and I don't know if there's even a docblock convention for "note that this property might be deliberately uninitialized, when it is, that means this ...". Since we now have union types, you can actually be a lot more explicit about the extra state, and use something like "int|false|null"; in 8.1, you'll also be able to use "int|SomeEnum|null". Since those are real types, with real values, no extra functions need to be added to the language, and everything feels a lot less "magic".

I have seen quite a few places where it occurs - for example with setter injection in frameworks, as an alternative to setting a property in the constructor.

Just to reiterate, the new function would *only* be useful if you were trying to distinguish the uninitialized state from a null value. If you have a property which you *know* might not be provided, you already have "null" to represent that. For instance, a property that might hold an instance of LoggerInterface, but only if the user calls a setLogger method, can be declared as "?LoggerInterface $logger=null", and tested with "isset($this->logger)". PS: A much sillier reason why I hate "uninitialized" is that I consistently misspell it as "unitialized" :P -- Rowan Tommins [IMSoP]