[perl #130498] [BUG] roundrobin doesn't work as expected on arrays

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# New Ticket Created by  Michael Schaap 
# Please include the string:  [perl #130498]
# in the subject line of all future correspondence about this issue. 
# <URL: https://rt.perl.org/Ticket/Display.html?id=130498 >


     my @l = (0,1,2),(3,4,5),(6,7);
     say roundrobin(|@l);

outputs

     (((0 1 2) (3 4 5) (6 7)))

instead of the expected

     ((0 3 6) (1 4 7) (2 5))

The following *does* work:

     my $l = ((1,2,3),(4,5,6),(7,8));
     say roundrobin(|$l);

Note that zip (the function) has the same issue, but Z (the operator) 
does not:

     my @l = (0,1,2),(3,4,5),(6,7);
     my $l = ((0,1,2),(3,4,5),(6,7));
     say zip(|@l);
     say zip(|$l);
     say [Z] @l;
     say [Z] $l;

outputs:

     (((0 1 2) (3 4 5) (6 7)))
     ((0 3 6) (1 4 7))
     ((0 3 6) (1 4 7))
     ((0 3 6) (1 4 7))

Unfortunately, there is no operator for roundrobin (right?) that I can 
use as a workaround.

Latest Rakudo Star:

This is Rakudo version 2016.11 built on MoarVM version 2016.11
implementing Perl 6.c.