perl 继承小例子

<pre name="code" class="html"><pre name="code" class="html">[tomcat@wx02 test]$ pwd
/home/tomcat/test
[tomcat@wx02 test]$ cat Pkg1.pm
package Pkg1;
sub fun1 {print "aaaaaa\n";};
1;
[tomcat@wx02 test]$ cat Pkg2.pm
package Pkg2;
sub fun2 {print "bbbbbbbb\n";};
1;
[tomcat@wx02 test]$ cat Pkg3.pm
package Pkg3;
sub fun3 {print "ccccccccccccccccc\n";};
1;
[tomcat@wx02 test]$ cat scan.pm
package scan;
use base qw(Pkg1 Pkg2 Pkg3);
sub new {
my $invocant = shift;
my $class = ref($invocant) || $invocant;
my $self = {
};
bless $self, $class;
 return $self;
};
1;
[tomcat@wx02 test]$ cat a1.pl
use scan;
$ua=scan->new();
$ua->fun1();
$ua->fun2();
$ua->fun3();
&fun3();
[tomcat@wx02 test]$ perl a1.pl
aaaaaa
bbbbbbbb
ccccccccccccccccc
Undefined subroutine &main::fun3 called at a1.pl line 6.

/************************************************
[tomcat@wx02 tmp]$ pwd
/tmp
[tomcat@wx02 tmp]$ cat a1.pl 

use scan;
$ua=scan->new();
$ua->fun1();
$ua->fun2();
$ua->fun3();
&fun3();
[tomcat@wx02 tmp]$ perl a1.pl
Can't locate scan.pm in @INC (you may need to install the scan module) (@INC contains: /usr/local/perl/lib/site_perl/5.22.1/x86_64-linux /usr/local/perl/lib/site_perl/5.22.1 /usr/local/perl/lib/5.22.1/x86_64-linux /usr/local/perl/lib/5.22.1 .) at a1.pl line 2.
BEGIN failed--compilation aborted at a1.pl line 2.

/**********************************************
[tomcat@wx02 tmp]$ cat a1.pl
use lib '/home/tomcat/test';
use scan;
$ua=scan->new();
$ua->fun1();
$ua->fun2();
$ua->fun3();
&fun3();
[tomcat@wx02 tmp]$ perl a1.pl
aaaaaa
bbbbbbbb
ccccccccccccccccc
Undefined subroutine &main::fun3 called at a1.pl line 7.