Today I was surprised and pleased to find that I could apparently subscript
an array with a list of lists of indices, and get a list of slices back:
> my @array = 9 ... 0
[9 8 7 6 5 4 3 2 1 0]
> @array[map { $_, $_ + 1 }, ^9]
((9 8) (8 7) (7 6) (6 5) (5 4) (4 3) (3 2) (2 1) (1 0))
Neat! But when I tried to clean up my code a bit, it broke.
> my @index = map { $_, $_ + 1 }, ^9
[(0 1) (1 2) (2 3) (3 4) (4 5) (5 6) (6 7) (7 8) (8 9)]
> @array[@index]
(7 7 7 7 7 7 7 7 7)
Weird. But map returns a Seq, right? So maybe...
> @array[@index.Seq]
(7 7 7 7 7 7 7 7 7)
Hmm. How about:
> @array[@index.List]
((9 8) (8 7) (7 6) (6 5) (5 4) (4 3) (3 2) (2 1) (1 0))
That works again. But why? Is this the intended behavior? If so, is it
documented somwhere?
