How to declare type/size of tuple in a struct?

General Usage
1

Hi,

I have a struct such as below. I want to know how to declare the type of the field somedict.
The keys of somedict will be tuples. Each key will be a tuple of two tuples, first one of length size1 and second one of length size2. When I create the struct instance, I want to pass the values of size1 and size2. Is this possible to do? If yes, can you please give an example. If not, I would appreciate knowing that too, so that I don’t spend too much time looking for it.

Thank you.

mutable struct Example
    size1::Int64
    size2::Int64
    somedict:: ## Dict{(Tuple of size1, Tuple of size2), Float64}
end
2

I’m sceptical if something like this is possible because the size is not encoded in the type signature of Tuple. Of course you can use something like

mutable struct Example
    size1::Int64
    size2::Int64
    somedict::Dict{Tuple{Tuple, Tuple}, Float64}
end

and implement dynamic size checks.

3

Or you go this route:

mutable struct Example2{T1 <: Tuple, T2 <: Tuple}
    somedict::Dict{Tuple{T1, T2}, Float64}
end
2 Likes
4

Awesome! This seems like it will work. When I create the instance, it figures out the size of the tuple and the type of contents. I thought this would not be the case since we don’t specify the size and type of the content when declaring struct. Thank you!!