I suspect this affects many developers who cut their teeth on PHP but haven't kept up. The language has become a different beast, which is a strength for the community but a barrier to re-entry.
I suspect this affects many developers who cut their teeth on PHP but haven't kept up. The language has become a different beast, which is a strength for the community but a barrier to re-entry.
Adding generics to PHP would make CS fundamentalists somewhat happy, but do nothing to change the fundamental design of PHP nor offer any of the traditional benefits that generics offer to strongly-typed and compiled languages. And would be a massive headache to implement, while bulking an already heavy VM implementation.
Exactly. The type system was never built for anything even slightly more complex. Its basically annotations for primitive types and classes. PHP has always had an weak type system, so adding generics will most likely never happen.
> Adding generics to PHP would make CS fundamentalists somewhat happy
PHP has really only one collection datatype (the infamous array), so having generics would be tremendously useful, as an example you cant return an typed array from a function, witch is just really bad.
For an counter example, Python managed to do this, while also being a dynamic language, although having a stronger typing than PHP.
PHP chose to check types at runtime. To check that a value is really an array<int> the runtime could have to loop through the entire array. All the types PHP currently implements are simple and cheap to check. For more elaborate cases you need an offline checker like PHPstan and comment-based type annotations. (PHPstan catches 99% of issues before the runtime gets to it so for my own code I'd prefer the Python approach with its cleaner syntax.)
The runtime checking seems the key difference, not so much the historical strength of the type system. Python's language implementation does very little typechecking itself and PHP's third-party offline typecheckers are respectably advanced.
Why is it bad?
In particular, why is it worse than not being able to declare a typed array in your current scope? (I understand the basic argument in favor of typed arrays, but I also understand why PHP would choose not to go that route; I'm not sure I see how it's worse to not be able to return one from a function, given that they don't exist elsewhere.)
This could be the way PHP could go, they just need the lexer to handle types, and not do any runtime checking at all.
But i guess that goes against what the php devs want, but it sounds so wasteful, to typecheck the same code time after time even if it passed some sort of initial "compile time step".
A even more simpler example is An array of some sort of Item. I cant return array(Item), but i only can return an array.
Yes array is the evil collection type of everything, but that's how it's meant to work. Array is the quick and dirty 'throw everything in there' thing. PHP has classes and they're very full featured and offer lots of type safety - use those.