Add Type::getLastIterableValueType()

[herndlm]

just playing around, kind of POC for moving more array-related methods to Type which I mentioned in #1801 (comment). I'm not sure about this or if this should be the direction to move forward for other array return type extensions too..

What I like

• no special constant array handling and union type building anymore in ArrayPopFunctionReturnTypeExtension. I actually love that

What I dislike

• it's basically just for constant array and array_pop in particular
• boiler plate code in some type classes, but this is already minimized thanks to the new array traits
• naming-wise it's maybe hard to understand in some cases, e.g. how would flip() be called on Type and what do people expect it to do ..
• not much related to this PR, but there's also MaybeIterableTypeTrait and NonIterableTypeTrait which are kind of related to the new array type traits IMO

Most likely this is the best-case example and others will be more complicated to move over.

This PR is really mostly just for discussing this to not do this in other PRs that are not related :)

[ondrejmirtes]

This totally makes sense to me. Maybe we could tackle first value at the same time? Thanks 😊

[ondrejmirtes]

BTW a random thought - don't feel obligated to get the design right the first time, it doesn't have to be perfect 😊 We'll eventually deprecate some of the new methods anyway, as we come up with better alternatives 😊

[herndlm]

BTW a random thought - don't feel obligated to get the design right the first time, it doesn't have to be perfect 😊 We'll eventually deprecate some of the new methods anyway, as we come up with better alternatives 😊

Yes. But you know, it is very important that they are sorted in the right order 😅

[herndlm]

I saw a couple more cases like this one, expect more PRs :) I'll look at the complex ones at the end

[herndlm]

this is ready and I'm eager to add a couple more 😊

[ondrejmirtes]

Thank you :)