Is there a way to create a custom data structure that can be used with the for loop?
I figured that such data structure needs to be “indexable” given the error I get:
type 'MyCustomType' is not indexable and not a range
So question is, can I also define a custom data type that is “indexable”
By the way I am aware of ability to create a custom iterator that can be used with a while loop but this question is more about exploring and understanding Zig better: what can and cannot be done.
As far as I know, it is not possible to implement some magic method to make your data structure work with a for loop.
According to the docs here, a for loop iterates over slices and arrays, no mention of implementing it for other types are made.
But I’d be glad to be proven wrong.
Other than exposing an array or slice, you can expose a range:
I think an iterator is usually the right way if you don’t have a slice/array.
No, you can’t. It’s by design, the whole avoiding hidden control flow principle.
Explicit iterators are the preferred way.
Your data structure also could have a field with a slice that can be used for iteration similar to std.ArrayList’s .items.
Or you could have a method that returns a slice, but if there is no easy way to create such a slice, then iterators may be the best other option.