I thought I understood hash arrays until I encountered this: 
use strict;

my @hashes = ({}) x 10;
$hashes[$_]{$_} = 1 foreach (0 .. 9);

foreach (0 .. 9) {
  print join(':', keys %{$hashes[$_]}), "\n"
}

[download]
which prints: 
6:3:7:9:2:8:1:4:0:5
6:3:7:9:2:8:1:4:0:5
6:3:7:9:2:8:1:4:0:5
6:3:7:9:2:8:1:4:0:5
6:3:7:9:2:8:1:4:0:5
6:3:7:9:2:8:1:4:0:5
6:3:7:9:2:8:1:4:0:5
6:3:7:9:2:8:1:4:0:5
6:3:7:9:2:8:1:4:0:5
6:3:7:9:2:8:1:4:0:5

[download]
What gives? I was expecting it to output: 
0
1
2
3
4
5
6
7
8
9

[download]
('Using ActivePerl 5.8.4 on Win XP.)

Thanks,
-Phil

Edit: Oh nevermind. I know what the problem is: every element of the array contains a reference to the same hash. D'oh!

This fixes the problem: 

my @hashes = map{{}} (0 .. 9);

[download]

-Phil

In reply to Array of hashes misbehaving? by Dr. Mu

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