Suppose I have a CartesianRange and want to access a sub-range.
start = CartesianIndex((1,1,1))
stop = CartesianIndex((5,5,5))
cr = CartesianRange{start, stop)
Something like:
sub_cr = SubCartesianRange(cr,x,y) where x,y are arbitrary CartesianIndexes
within
cr.
then I could do
for a in sub_cr
...
end
length(sub_cr)
etc.
I note that constructing CartesianRange(x,y) is valid code, but won't work
because, we need to somehow embed start, stop into the sub-range.
Also, it is possible for some x[i] > y[i], and I think the logic for
CartesianRanges requires x[i] <= y[i] for all i.
Is there something for sub-ranges like this already?
