package - create dispatch table inside class constructor in perl -

i trying create dispatch table inside class constructor.execution fails below mentioned error.

error: use of uninitialized value in subroutine entry @ ../lib/parser.pm . can't use string ("") subroutine ref while "strict refs" in use @ ../lib/parser.pm.

code:

package parser;  use strict; use warning;  @packet = ("join","release","status"); #constructor  sub new {         ($class) = shift;         $self = {            _callermdn => shift,            _calleelist => shift,            _serverip => shift,            _packethandler => {                 join => \&joinhandler, #dispatch table,variable "join" stores func reference                 release => \&releasehandler, #variable "release" stores func reference                 status => \&statushandler #variable "stores" stores func reference                 },            _mdnhandler => {},          };          print ("the server ip = $self->{_serverip}\n") if ($debug);         print ("callermdn = $self->{_callermdn}\n") if ($debug);         print ("tcpdump file name = $self->{_tcpdumpfile}\n") if ($debug);      bless( $self, $class );     return $self;  }  sub start {     ($self,$data) = @_;     if ($data ~= "incoming packet") {          $self->{_packethandler}->{$packet[0]}->($data);#**error while calling "joinhandler" function**     }     elsif ($data ~= "outgoing packet"){          $self->{_packethandler}->{$packet[1]}->($data);#**error while calling "releasehandler" function**     }     else {          $self->{_packethandler}->{$packet[2]}->($data);#**error while calling "statushandler" function**     }   }  sub joinhandler {     ($self,$data) = @_;     #parse packet     print ("incoming packet parsed"); }  sub releasehandler {    ($self,$data) = @_;    #parse packet    print ("outgoing packet parsed"); }  sub statushandler {     ($self,$data) = @_;     #parse packet     print ("status packet"); } 

please me understand , resolve issue.

i see quite few problems.

1. use warning; should use warnings;

2. you forgot my @packet @ top of package

3. in sub start have =~ backwards ~=. should eq anyways.

4. $debug isn't declared anywhere.

you might find useful take advantage of perl -c, checks syntax(also runs begin blocks too), when run problems.