use strict;
use warnings;

{
    print "This is the original approach, reusing \$attrHash\n";

    my $result = [];
    my $attrHash = {};

    for( 1..5 )
    {       
        print $attrHash, "\n";
        push( @$result, $attrHash );
    }
}

{
    print "This uses a new hash each time through the loop\n";

    my $result = [];

    for( 1..5 )
    {       
        my $attrHash = {};
        print $attrHash, "\n";
        push( @$result, $attrHash );
    }
}

__END__

This is the original approach, reusing $attrHash
HASH(0x2254c8)
HASH(0x2254c8)
HASH(0x2254c8)
HASH(0x2254c8)
HASH(0x2254c8)
This uses a new hash each time through the loop
HASH(0x225504)
HASH(0x225534)
HASH(0x225324)
HASH(0x2254e0)
HASH(0x183c1d0)