[ragnese]

As a statically typed language, I feel like it doesn't even take much to explain why it's actually the worst, except for C. But at least C is necessary in some domains.

The type system is weaker than Java, which is a low bar.

It has no generics, which means no real containers, no generic functions without dropping all typing, no type-hinted arrays.

Arrays are also not objects, so they don't conform to any interfaces, which is related to the "no real containers" issue.

It took until version 7.4 to actually have covariance and contravariance! Before that it didn't even implement inheritance correctly!

You can't typehint for function-as-param beyond just writing `callable`. So if you want to use those nice lambdas and still be statically typed, you're SOL.

It's definitely fast for a scripting language! So, that's fair. But it's still way slower than many other good backend languages: Java and other JVM languages: Kotlin, Scala, maybe Clojure?, Go, Rust if you're feeling frisky.

I've never used Ruby and I'm generally biased against dynamically typed languages, so that's the background for my assessment. The dynamic languages I've used in anger are Python, JavaScript, Elixir, and Clojure.

The package manager is better than the disaster that Python was the last time I used it. Agreed. It's also better than NPM, but not enough to matter most of the time. It's not better than Hex or Lein. Also, managing packages is a) not the language, which is what I criticized, and b) not where you spend most, or even a large part, of your dev time.

Looking at PHP as a dynamic language, I'd say that the built-in array is still a huge disappointment and the API sucks compared to either of Python's dict or list. It's much cleaner in JavaScript, Clojure, Elixir, and Python to define and operate on new, untyped, objects.

Also, for a dynamic language, I'd at least want SOME benefit to it being dynamic. For JS, Clojure, Elixir, and Python, the REPLs are great. The PHP REPL is... primitive.

None of the things you mentioned in PHP are actually better than any other language I've used except for the package manager. Its lambdas are not even better than any of the languages I've listed. In 2020, decent lambda syntax is table-stakes.

[core-questions]

> It has no generics, which means no real containers, no generic functions without dropping all typing, no type-hinted arrays.

These things are a little advanced for the likes of me. Any chance you'd be so kind as to give me an example of something I can't easily do because of not having this?

> It's definitely fast for a scripting language! So, that's fair. But it's still way slower than many other good backend languages

But those languages require compilation and deploy cycles that are way longer than just getting files on disk, so the total cycle time of development may end up being longer in many cases. It's a tradeoff. PHP probably shouldn't be used for performance-critical things, sure, but then neither should any other dynamic language.

[ragnese]

> These things are a little advanced for the likes of me. Any chance you'd be so kind as to give me an example of something I can't easily do because of not having this?

Well, you can do whatever you want in a dynamically typed language. I was discussing the shortcomings if you choose to use PHP's type system.

If I'm using my static types and see `function foo(): Bar` I take comfort that I will receive a `Bar`. If I see `function foo(): array` I have absolutely no idea what that array is. Is it a list of `Bar`? Is it a dictionary of some kind? Is it a heterogeneous list of bools, ints, and Maseratis?

Also, real containers are useful. A true array is a contiguous slab of memory. PHP's array is not. The performance characteristics will be very different. If you had a `Set<T>` type, you could guarantee that there are no duplicates in the set. That is sometimes very useful. No such thing in PHP. PHP arrays can't even be used as a real `Map<String, T>` because if you do `$arr["1"] = new T()`, it wont actually have "1" as a key! It'll transform the "1" into 1 and store it in the 1th slot, like an array!!! Totally flipping useless.

> But those languages require compilation and deploy cycles that are way longer than just getting files on disk, so the total cycle time of development may end up being longer in many cases.

Are you suggesting that you write PHP code and then plop in on a production server without running tests? Because running your tests is comparable to the compile cycle of Java et al. Except in those cases I don't have to write entire classes of tests, whereas you should be writing type-checking-style tests on your PHP code. You just have to be the compiler to make sure your inputs are validated correctly.

> PHP probably shouldn't be used for performance-critical things, sure, but then neither should any other dynamic language.

Then what was the point in comparing PHP's speed to Python? They're both slow and shouldn't be used for performance-critical things. That's fine, but then find me a selling point.