NAME

       Module::Extract::Use - Discover the modules a module explicitly uses

SYNOPSIS

               use Module::Extract::Use;

               my $extor = Module::Extract::Use->new;

               my @modules = $extor->get_modules( $file );
               if( $extor->error ) { ... }

               my $details = $extor->get_modules_with_details( $file );
               foreach my $detail ( @$details ) {
                       printf "%s %s imports %s\n",
                               $detail->module, $detail->version,
                               join ' ', @{ $detail->imports }
                       }

DESCRIPTION

       Extract the names of the modules used in a file using a static analysis. Since this module
       does not run code, it cannot find dynamic uses of modules, such as "eval "require
       $class"". It only reports modules that the file loads directly or are in the import lists
       for parent or base.

       The module can handle the conventional inclusion of modules with either "use" or "require"
       as the statement:

               use Foo;
               require Foo;

               use Foo 1.23;
               use Foo qw(this that);

       It now finds "require" as an expression, which is useful to lazily load a module once (and
       may be faster):

               sub do_something {
                       state $rc = require Foo;
                       ...
                       }

       Additionally, it finds module names used with "parent" and "base", either of which
       establish an inheritance relationship:

               use parent qw(Foo);
               use base qw(Foo);

       In the case of namespaces found in "base" or "parent", the value of the "direct" method is
       false. In all other cases, it is true. You can then skip those namespaces:

               my $details = $extor->get_modules_with_details( $file );
               foreach my $detail ( @$details ) {
                       next unless $detail->direct;

                       ...
                       }

       This module does not discover runtime machinations to load something, such as string
       evals:

               eval "use Foo";

               my $bar = 'Bar';
               eval "use $bar";

       If you want that, you might consider Module::ExtractUse (a confusingly similar name).

       new Makes an object. The object doesn't do anything just yet, but you need it to call the
           methods.

       init
           Set up the object. You shouldn't need to call this yourself.

       get_modules( FILE )
           Returns a list of namespaces explicity use-d in FILE. Returns the empty list if the
           file does not exist or if it can't parse the file.

           Each used namespace is only in the list even if it is used multiple times in the file.
           The order of the list does not correspond to anything so don't use the order to infer
           anything.

       get_modules_with_details( FILE )
           Returns a list of hash references, one reference for each namespace explicitly use-d
           in FILE. Each reference has keys for:

                   namespace - the namespace, always defined
                   version   - defined if a module version was specified
                   imports   - an array reference to the import list
                   pragma    - true if the module thinks this namespace is a pragma
                   direct    - false if the module name came from parent or base

           Each used namespace is only in the list even if it is used multiple times in the file.
           The order of the list does not correspond to anything so don't use the order to infer
           anything.

       error
           Return the error from the last call to "get_modules".

TO DO

SEE ALSO

       Module::ScanDeps, Module::Extract

SOURCE AVAILABILITY

       The source code is in Github:

               https://github.com/briandfoy/module-extract-use

AUTHOR

       brian d foy, "<bdfoy@cpan.org>"

COPYRIGHT AND LICENSE

       Copyright © 2008-2022, brian d foy "<bdfoy@cpan.org>". All rights reserved.

       This project is under the Artistic License 2.0.