Uninitialized AxisArray constructor

Is there any reason there's currently no constructor to create an uninitialized AxisArray? I.e. something like:

AxisArray{T,N,D}(axes::Axis...)

This seems pretty straightforward, I'm happy to submit a PR - just wanted to check that it wasn't intentionally omitted for some reason.

There's a potential conflict between N and length(axes) - presumably N would be the canonical dimensionality with axes either truncated or extended (with the standard default dimension names and zero-length?) as needed.

Edit: To avoid the over/under-specification, an alternative would be to deviate from the AxisArray type parameter order specification and use AxisArray{T,D} or just AxisArray{T} (where T is a concrete child of AbstractArray). I assume that's frowned upon though - if it's even possible (I'm not clear on how exactly type parametrization works on constructor methods or methods in general, really - any recommended resources for that?).

Start at the AxisArray constructor entry points and type-parameter definition; the issue names no files or tests. Resolve whether dimensionality should follow N or the supplied axes, then add the uninitialized-construction behavior and tests covering the chosen API.