circular.pm

来自「PERL语言资料 可以用于PERL程序设计」· PM 代码 · 共 54 行

#!/usr/bin/perl
# Fig. 14.18: Circular.pm
# Using the DESTROY function to destroy objects.

package Circular;

use strict;
use warnings;

sub new {
   my $class = shift();
   
   my $a;
   my $b = \$a;

   $a = \$b;
   
   my $self = {};

   $self->{ name } = shift();
   $self->{ Circle } = \$a;
   
   bless( $self, $class );
   return $self;
}

sub sayHi {
   my $self = shift();

   print( "$self->{ name } says hi.\n" );
}

sub DESTROY {
   my $self = shift();
   
   print( "Destroying $self->{ name }.\n" );   
   ${ $self->{ Circle } } = undef;
}

return 1;

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