Idea to better implement subpopulation functions | enhancement about dispersal.jl HOT 2 CLOSED

First we need to get your code updated to get rid of all those macros! Can you push your latest code? then I can convert it and put in a PR. It will be so much easier to discuss after that.

For having multiple sub-populations in the grid, for intrinsicrate use a Tuple. (but you might not even need to lock it like this)

struct DiscreteGrowthRate{R,W,GR<:Tuple,I}
    intrinsicrate::GR
    numberSupPop::I
end

With a Tuple you can just map over the populations and growth rates, and it will handle any number of sub populations making this generic to all similar problems:

@inline function applyrule(data, rule::DiscreteGrowthRate, pops, index)
    map(pops, rule.intrinsicrate) do pop, ir
         ir * pop * (1 - sum(pops) / rule.carrycap)
    end
end

(map with a Vector is allocating and much slower, and can't be optimised the same way a Tuple can be. We also need to return a Tuple to be written back to the N separate grids, which just works using a Tuple for intrinsicrate)

Edit: you could get rid of the <:Tuple limitation, then a single instrinsicrate would also work

from dispersal.jl.

Great.
I just send a PR #64

from dispersal.jl.