So don't apply it to all the lines. This seems to produce something close to your desired output:

my %seen;
for (my $i = 1; $i < @lines; $i++)
{
    next if $seen{$i};
    my @results = line_closure($i);
    print Dumper \@results;
    $seen{$_}++ for @results;
}

[download]
perl -E'sub Monkey::do{say$_,for@_,do{($monkey=[caller(0)]->[3])=~s{::}{ }and$monkey}}"Monkey say"->Monkey::do'

In reply to Re^3: I need help with some recursion by tobyink
in thread I need help with some recursion by ragnarokPP

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