I'm doing an exercise from "Intermediate Perl" -- anyway, in the below code, the YAML Dump comes out correct but the foreach (marked HERE) yields just a single array reference (ARRAY), as if tmp only had one element, although it is the exact same array. 
#!/usr/bin/perl -w
use strict;

use YAML::XS;

my %all;

open(INPUT,"<coconet.dat") || die "Can't open coconet.dat";
while (<INPUT>) {
    if ($_ =~ /^#/) { next }
    my ($src, $dest, $bytes) = split;
    $all{$src}{$dest}+=$bytes;    
}
close(INPUT);

my @reflist = sort { ${$$b}[2] <=> ${$$a}[2] } map \&buildlist($_), ke
+ys %all;   

foreach my $ref (@reflist) { 
    print "${$$ref}[0] ${$$ref}[2]\n";
    my @tmp=@{$$ref}[3];
#HERE    foreach my $line (@tmp) { print "\t$line\n" }
    print Dump @tmp;
}

sub buildlist {
    my $site = $_;
    my @tmp;
    $tmp[0]=$site;
    $tmp[1]=\%{$all{$site}};
    foreach (keys %{$tmp[1]}) { $tmp[2]+=${$tmp[1]}{$_} }
    @{$tmp[3]} = sort { ${$tmp[1]}{$b} <=> ${$tmp[1]}{$a} } keys %{$tm
+p[1]};
    return \@tmp;   # 0=site name, 1=hash ref, 2=total bytes, 3=sorted
+ dest refs
}

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Why would there be this difference and what's wrong with my foreach??

In reply to array reference madness by Anonymous Monk

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