D:\>cat temp
#! /usr/local/bin/perl

BEGIN
{
    push ( @INC, "$ENV{HOME}/Filesys-DiskSpace-0.05/lib"); # Filesys::
+DiskSpace - Perl df
}

use strict;
use warnings;
require Filesys::DiskSpace;

# file system /home or /dev/sda5
my $dir = "/home";

# get data for /home fs
my ($fs_type, $fs_desc, $used, $avail, $fused, $favail) = Filesys::Dis
+kSpace::df $dir;
# calculate free space in %
my $df_free = (($avail) / ($avail+$used)) * 100.0;

# display message
my $out = sprintf("Disk space on $dir == %0.2f\n",$df_free);
print $out;

D:\>perl -MO=Deparse,-p temp
sub BEGIN {
    push(@INC, "$ENV{'HOME'}/Filesys-DiskSpace-0.05/lib");
}
use warnings;
use strict 'refs';
require Filesys::DiskSpace;
(my $dir = '/home');
(my($fs_type, $fs_desc, $used, $avail, $fused, $favail) = $dir->Filesy
+s::DiskSpace::df);
(my $df_free = (($avail / ($avail + $used)) * 100));
(my $out = sprintf("Disk space on $dir == %0.2f\n", $df_free));
print($out);
temp syntax OK
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D:\>echo Can't call method "Filesys::DiskSpace::df" without a package 
+or object reference at ./try.pl line 27. | splain
Can't call method "Filesys::DiskSpace::df" without a package or object
        reference at ./try.pl line 27.  (#1)
    (F) You used the syntax of a method call, but the slot filled by t
+he
    object reference or package name contains an expression that retur
+ns a
    defined value which is neither an object reference nor a package n
+ame.
    Something like this will reproduce the error:

        $BADREF = 42;
        process $BADREF 1,2,3;
        $BADREF->process(1,2,3);
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