Generic type for array and frozenarray

[perlinm]

I have a suite of helper functions which I want to accept both array and frozenarray arguments, as in

def func(var: array[bool, N] | frozenarray[bool  N], ...): ...

Union-ing types in this way throws a Guppy error.

I can hack my way to the desired functionality by writing copies of the function and then using function overloading to accept different input types, but this quickly grows into quite a mess.

Is there a suitable generic type I can use? Some other way to do this cleanly?

Another thought: I suppose if var is a frozenarray, I could always pass it as func(var.mutable_copy()), ...), but that seems to go against the point of having frozenarrays(?)

[ss2165]

Guppy does not support union types in the way that python does, and does not intend to. The closest planned feature is Sum/Enum types, which are full structured unions.

More in the near term though, Protocols are in progress and would also be a good way of implementing your generic functionality. Your var would be generic over protocols that implement your func needs.

In the meantime - just using array and passing in var.mutable_copy() is the best workaround, frozenarray only really exists for performance reasons and if it is not a bottleneck you need not worry about converting it.

[perlinm]

So it sounds like I need to just wait for Protocols to be recognized by Guppy, yes?

[ss2165]

Yes I suspect you will be able to define a function over an iterator protocol