>perl -wMstrict -e
"use 5.014;
 ;;
 package Foo {
   ;;
   sub new { bless [] };
   ;;
   sub msg {
     my $self = shift;
     my ($destination) = @_;
     printf qq{On my way to '%s'. }, $destination;
     my $coderef = $self->can($destination);
     return print qq{Cannot get there. \n} unless $coderef;
     $self->$coderef($destination);
     }
   ;;
   sub Berlin { my $self = shift;  print qq{I am in $_[0]! \n};  }
   ;;
   sub Paris  { my $self = shift;  print qq{Arrived in $_[0]! \n}; }
   ;;
   }
 ;;
 my $obj = Foo->new;
 $obj->msg('Berlin');
 $obj->msg('Paris');
 $obj->msg('London');
"
On my way to 'Berlin'. I am in Berlin!
On my way to 'Paris'. Arrived in Paris!
On my way to 'London'. Cannot get there.