feat: allow making a weighted container ordered

[LordMidas]

The primary purpose is to allow a foreach (item in container) type iteration and for loop iteration with indices instead of the current foreach (item, weight in container). This helps the container to be used interchangeably with arrays without having to do a typeof check and duplicate foreach loops separately for arrays and weighted containers.

I ran into this issue while coding the Dynamic Spawns Framework whereby the same member variable in a class could be an array or a weighted container. In many functions I want to iterate over that variable in foreach loops and sometimes in for loops with using i as index while being agnostic to its type. Having the possibility of an ordered weighted container allows me to set it as ordered during creation, and then the class can do its thing while not worrying about it.

While, in theory, we could implement a child class of WeightedContainer that is ordered (I did that in Dynamic Spawns and called it WeightedArray) - but that violates the Liskov Substitution Principle, which is why I'd like to have a basic implementation of this in the base class.

Alternatively, we implement a base abstract class and then inherit WeightedContainer from it and WeightedArray from it separately. Because ideally I'd like the WeightedArray to support all kinds of array functions e.g. pop(), push() etc.

[Enduriel]

We discussed and this is cool but as you said it should be a sibling of WeightedContainer and seems like it requires still quite a bit of work

[Suor]

If you don't really care about order but just want to iterate over index, item instead of index, weight then you may just add an iterator method to it:

class WeightedContainer {
    ...    
    function items() {
        foreach (k, _ in this.Table) yield k;
    }
}

// Use
local items = type cont == "array" ? cont : cont.items();
foreach (item in items) {
    // ... do stuff ...
}

Unfortunately typeof/items cannot be removed completely because WeightedContainer already has a way to iterate. Can pass cont.items() to functions waiting for arrays in many cases though.

[Suor]

Another approach is to provide external to WeightedContainer function, which will know what to do:

// Util.iter() supposed to know what "items" mean for different types of containers,
// i.e. typeof and iterator will be hidden there.
foreach (item in Util.iter(cont)) {
    // ... do stuff ...
}