Hi, all monks:

I encounted a strange problem with hash in Perl, I have write a tiny script to demostrate this problem:

#!/usr/bin/perl
 use strict;
 use warnings;

 my $heap = {};

 $heap->{'172.16'} = 1;
 print "\$heap->{'172.16'}: $heap->{'172.16'}\n";
 print "\$heap->{172.16}: $heap->{172.16}\n";

 $heap->{'127.2'}{'127.1.0.2'} = 2;
 print "\$heap->{'127.2'}{'127.1.0.2'}: $heap->{'127.2'}{'127.1.0.2'}\
+n";
 print "\$heap->{127.2}{127.1.0.2}: $heap->{127.2}{127.1.0.2}\n";
[download]

and here is the executed result:

$heap->{'172.16'}: 1
$heap->{172.16}: 1
$heap->{'127.2'}{'127.1.0.2'}: 2
Use of uninitialized value in concatenation (.) or string at /home/lar
+ry/project/sysmonitor/test/testHash2.pl line 28.
$heap->{127.2}{127.1.0.2}:
[download]

What surprise me is that $heap->{'127.2'}{'127.1.0.2'} is not the same as $heap->{127.2}{127.1.0.2}.

Can anyone give some tips?

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