nothing.jl

struct Solution
    res::Union{Int64, Nothing}
end

function ex_div(a, b)::Solution
    if b == 0
        Solution(nothing)
    else
        Solution(Int64(a / b))
    end
end

result = ex_div(10, 0)
if isnothing(result.res)
    println("Nothing")
else
    println(result.res)
end