[julia-users] Re: Never use Containers of abstract types? Aways Union with containers of subtypes, or use containers of Typed Parameterized containers?

[Steven G. Johnson]

On Thursday, June 11, 2015 at 6:21:01 AM UTC+2, Lyndon White wrote:
>
> Containers of abstract types are not performant,
> However containers of concrete types are not generic.
>

That's why you should use parameterized types like Matrix{T}.  This gives 
you an abstract family (Matrix) of concrete types (Matrix{T}), giving 
mostly the best of both worlds (generic code + performance).