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    can create the object the usual way, using the "new()" constructor, and
    call any method on it, and all methods will do the same - nothing.
    (Actually, it always returns the same "Class::Null" singleton object,
    enabling method chaining.) It's effectively a catch-all object. We can
    use this class with our own object like this:

      package MyObject;

      use Class::Null;

      # some class constructor and accessor declaration here

      sub init {
        my $self = shift;
        ...
        $self->log(Class::Null->new);
        ...
      }

      sub do_it {
        my $self = shift;
        $self->log->log(level => 'debug', message => 'starting to do it');
        ...
        $self->log->log(level => 'debug', message => 'still doing it');
        ...
        $self->log->log(level => 'debug', message => 'finished doing it');
      }

    This is only one example of using a null class, but it can be used
    whenever you want to make an optional helper object into a mandatory
    helper object, thereby avoiding unnecessarily complicated checks and
    preserving the transparency of how your objects are related to each
    other and how they call each other.

    Although "Class::Null" is exceedingly simple it has been made into a
    distribution and put on CPAN to avoid further clutter and repetitive
    definitions.

METHODS
  new
    Returns the singleton null object.

  Any other method
    Returns another singleton null object so method chaining works.

OVERLOADS
    Boolean context
        In boolean context, a null object always evaluates to false.

    Numeric context
        When used as a number, a null object always evaluates to 0.

    String context
        When stringified, a null object always evaluates to the empty
        string.

INSTALLATION
    See perlmodinstall for information and options on installing Perl
    modules.

BUGS AND LIMITATIONS
    No bugs have been reported.

    Please report any bugs or feature requests through the web interface at
    <http://rt.cpan.org/Public/Dist/Display.html?Name=Class-Null>.

AVAILABILITY
    The latest version of this module is available from the Comprehensive
    Perl Archive Network (CPAN). Visit <http://www.perl.com/CPAN/> to find a
    CPAN site near you, or see <http://search.cpan.org/dist/Class-Null/>.

    The development version lives at <http://github.com/hanekomu/Class-Null>
    and may be cloned from <git://github.com/hanekomu/Class-Null.git>.
    Instead of sending patches, please fork this project using the standard
    git and github infrastructure.

AUTHOR
    Marcel Gruenauer <marcel@cpan.org>

COPYRIGHT AND LICENSE
    This software is copyright (c) 2005 by Marcel Gruenauer.

    This is free software; you can redistribute it and/or modify it under
    the same terms as the Perl 5 programming language system itself.