Recipe 12.18. Example: Module Template
Author: Tom Christiansen & Nathan Torkington
Date: 1999-07-02T01:42:05Z

#

| Chapter 12 Packages, Libraries, and Modules |

## 12.18. Example: Module Template

Following is the skeleton of a module. If you want to write a module of your own, you can copy this and customize it.

    package Some::Module;  # must live in Some/Module.pm

    use strict;

    require Exporter;
    use vars       qw($VERSION @ISA @EXPORT @EXPORT_OK %EXPORT_TAGS);

    # set the version for version checking
    $VERSION     = 0.01;

    @ISA         = qw(Exporter);
    @EXPORT      = qw(&func1 &func2 &func4);
    %EXPORT_TAGS = ( );     # eg: TAG => [ qw!name1 name2! ],

    # your exported package globals go here,
    # as well as any optionally exported functions
    @EXPORT_OK   = qw($Var1 %Hashit &func3);

    use vars qw($Var1 %Hashit);
    # non-exported package globals go here
    use vars      qw(@more $stuff);

    # initialize package globals, first exported ones
    $Var1   = '';
    %Hashit = ();

    # then the others (which are still accessible as $Some::Module::stuff)
    $stuff  = '';
    @more   = ();

    # all file-scoped lexicals must be created before
    # the functions below that use them.

    # file-private lexicals go here
    my $priv_var    = '';
    my %secret_hash = ();

    # here's a file-private function as a closure,
    # callable as &$priv_func.
    my $priv_func = sub {
        # stuff goes here.
    };

    # make all your functions, whether exported or not;
    # remember to put something interesting in the {} stubs
    sub func1      { .... }    # no prototype
    sub func2()    { .... }    # proto'd void
    sub func3($$)  { .... }    # proto'd to 2 scalars

    # this one isn't auto-exported, but could be called!
    sub func4(\%)  { .... }    # proto'd to 1 hash ref

    END { }       # module clean-up code here (global destructor)

    1;

12.17. Building and Installing a CPAN Module |  | 12.19. Program: Finding Versions and Descriptions of Installed Modules