Dynamic arrays

[Akuli]

The self-hosted compiler already has a few dynamic arrays, i.e. arrays whose size grows as needed. Many languages have something like this:

• Python: list
• C++: vector
• C: does not come in standard library, but can be implemented (see List in the Jou compiler)

Jou doesn't support these very well. Currently my Jou code has a realloc() whenever another item is added to the list, which works but isn't very efficient.

To implement dynamic arrays in Jou, I think I want something similar to the solution in C, so some kind of combination of macros and anonymous structs, neither of which is currently supported in Jou.

[Moosems]

Will there also be an array that can contain multiple types?

[Akuli]

You can already use union and enum to wrap multiple types into a single container type. This is not documented anywhere though.

[Akuli]

Very much related to #527