On Mar 20, 6:09 am, Robert Dober <robert.do... / gmail.com> wrote:
> >  If the global $, is okay, you can just do arr.join, but if you can't
> >  be sure, then arr.join ""
>
> There is no  need to use the empty string as parameter it is the
> default,

No, $, is the default.

irb(main):001:0> [3,4].join
=> "34"
irb(main):002:0> $, = '-'
=> "-"
irb(main):003:0> [3,4].join
=> "3-4"