Nice one.. is there a @nexprs that can take a compile-time iterable, and
map function that produces a child expression for each item? Kind of like
replacing $N with "1:5" rather than one value at a time. That's what I'm
really looking for..
On Monday, February 10, 2014 11:42:31 PM UTC+11, Tim Holy wrote:
>
> On Monday, February 10, 2014 03:16:18 AM Fil Mackay wrote:
> > Is there an equivalent that allows a for loop iterator to construct the
> > type.. Base.Cartesian.@forexprs perhaps? :)
>
> Base.Cartesian is a slightly-enhanced version of the original Cartesian.jl
> package; the README there is (in my personal opinion) quite thorough. The
> version in base is intentionally undocumented since we don't plan on
> exporting
> it.
>
> But I'm wondering if perhaps you're simply wondering if you can replace
> "5" in
> my example with something else. The answer is yes:
>
> julia> for N = 1:5
> typename = symbol(string("MyType", N))
> @eval begin
> type $typename
> Base.Cartesian.@nexprs $N i->a_i::Int
> end
> end
> end
>
> julia> MyType2.names
> (:a_1,:a_2)
>
> julia> MyType4.names
> (:a_1,:a_2,:a_3,:a_4)
>
>
