diff(A::SArray, [dim])?

[wsshin]

Is there a plan to implement diff(A::SArray, [dim])? This should be doable, because the size of the result can be predicted from size(A).

[andyferris]

All the reducer and cumulative methods (and diff) require both size(A) and dim to infer the size, and unfortunately there is no way to get at the (probably constant value) dim during compilation time. If you want to do this on vectors, then no problem, but in general we have to do something a bit different.

I was thinking Val{dim} might make sense for these functions, in place of dim. Does this sound reasonable?

PS - We welcome PRs :)

[andyferris]

See #65 for related discussion

[wsshin]

Your answer in #65 is great. Thanks!

Yes, I think being able to pass Val{dim} will be useful. Motivated by your encouragement to do PR, I have actually implemented diff(::StaticArray{T,N}, ::Type{Val{D}}). Which source file do you think this function should go? Maybe mapreduce.jl?

[wsshin]

Generated a PR: #86.

[andyferris]

Merged.