(Minor nit: it's not a command. It's accessing an array reference. Read up on Perl data structures.)
$slist->{data} is an array reference of other array references (the "rows" in the list) each item of which is a piece of data (the "columns" in each row). Fiddle about with this:
for my $row (@{$slist->{data}}) {
print "Row:\n";
for my $col (@{$row}) {
print " $col\n";
}
}
or use
Data::Dumper to visualize the data structure in a more Perlish way:
use Data::Dumper;
print Dumper($slist->{data}), "\n";
(Untested code.)