From: Robert Citek <robert.citek@...>
Date: 2007-12-20T08:58:34+09:00
Subject: slicing in ruby

Is there a way to slice an array like in perl?

For example, what's the ruby equivalent to doing this:

$ echo $(seq 1 10) | tee /dev/stderr |  perl -lane 'print join(" -- ",
@F[1,2,3,8,2,2]) '
1 2 3 4 5 6 7 8 9 10
2 -- 3 -- 4 -- 9 -- 3 -- 3

I can get this to work:

$ echo $(seq 1 10) | tee /dev/stderr |  ruby -lane 'print $F.join(" -- ") '
1 2 3 4 5 6 7 8 9 10
1 -- 2 -- 3 -- 4 -- 5 -- 6 -- 7 -- 8 -- 9 -- 10

and this:

$ echo $(seq 1 10) | tee /dev/stderr |  ruby -lane 'print $F[1,2].join(" -- ") '
1 2 3 4 5 6 7 8 9 10
2 -- 3

but not this:

$ echo $(seq 1 10) | tee /dev/stderr |  ruby -lane 'print
$F[1,2,3,8,2,2].join(" -- ") '
1 2 3 4 5 6 7 8 9 10
-e:1:in `[]': wrong number of arguments (6 for 2) (ArgumentError)
        from -e:1


There's probably some method I need to invoke, but which one?

Regards,
- Robert