Does anyone know why this code:

use strict;
use Data::Dumper;

sub sub_b ()
{
    my %hash1b = ();
    $hash1b{"key1"} = "1";

    print "calling sub_c from sub_b\n";
    sub_c (%hash1b);
}

sub sub_c (\%)
{
    my ($hash1c) = @_;

    print "sub_c arguments:" . Dumper (@_);
}

my %hash1a = ();
$hash1a{"key1"} = "1";

print "calling sub_b\n";
sub_b ();

print "\n";
print "calling sub_c directly\n";
sub_c (%hash1a);

[download]

returns:

   calling sub_b
   calling sub_c from sub_b
   sub_c arguments:$VAR1 = 'key1';
   $VAR2 = 1;

   calling sub_c directly
   sub_c arguments:$VAR1 = {
             'key1' => 1
           };

[download]

?
There appears to be a difference in the way sub_c interprets the parameter, depending of it is called directly or from within another sub. Could someone perhaps explain what is going on ?

In reply to Passing by reference from within a sub by arvid

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