Example: Module Template (Perl Cookbook, 2nd Edition)

## 12.22. 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;

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

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

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

>     use vars qw($Var1 %Hashit);
>     # non-exported package globals go here
>     our(@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 cleanup code here (global destructor)

>     1;

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