view release on metacpan or  search on metacpan

lib/Alien/Base.pm  view on Meta::CPAN

  $cmp = Alien::MyLibrary->version_cmp($x, $y)

Comparison method used by L</atleast_version>, L</exact_version> and
L</max_version>. May be useful to implement custom comparisons, or for
subclasses to overload to get different version comparison semantics than the
default rules, for packages that have some other rules than the F<pkg-config>
behaviour.

Should return a number less than, equal to, or greater than zero; similar in
behaviour to the C<< <=> >> and C<cmp> operators.

=head2 install_type

 my $install_type = Alien::MyLibrary->install_type;
 my $bool = Alien::MyLibrary->install_type($install_type);

Returns the install type that was used when C<Alien::MyLibrary> was
installed.  

If a type is provided (the second form in the synopsis)
returns true if the actual install type matches.  
For this use case it is recommended to use C<is_system_install> 
or C<is_share_install> instead as these are less prone to 
typographical errors.

Types include:

=over 4

=item system

The library was provided by the operating system

=item share

The library was not available when C<Alien::MyLibrary> was installed, so
it was built from source code, either downloaded from the Internet
or bundled with C<Alien::MyLibrary>.

=back

=head2 is_system_install

 my $type = $build->is_system_install;

Returns true if the alien is a system install type.  

=head2 is_share_install

 my $type = $build->is_share_install;

Returns true if the alien is a share install type.  

=head2 config

 my $value = Alien::MyLibrary->config($key);

Returns the configuration data as determined during the install
of C<Alien::MyLibrary>.  For the appropriate config keys, see
L<Alien::Base::ModuleBuild::API/"CONFIG DATA">.

This is not typically used by L<Alien::Base> and L<alienfile>,
but a compatible interface will be provided.

=head2 dynamic_libs

 my @dlls = Alien::MyLibrary->dynamic_libs;
 my($dll) = Alien::MyLibrary->dynamic_libs;

Returns a list of the dynamic library or shared object files for the
alien software.

=head2 bin_dir

 my(@dir) = Alien::MyLibrary->bin_dir

Returns a list of directories with executables in them.  For a C<system>
install this will be an empty list.  For a C<share> install this will be
a directory under C<dist_dir> named C<bin> if it exists.  You may wish
to override the default behavior if you have executables or scripts that
get installed into non-standard locations.

Example usage:

 use Env qw( @PATH );
 
 unshift @PATH, Alien::MyLibrary->bin_dir;

=head2 dynamic_dir

 my(@dir) = Alien::MyLibrary->dynamic_dir

Returns the dynamic dir for a dynamic build (if the main
build is static).  For a C<share> install this will be a
directory under C<dist_dir> named C<dynamic> if it exists.
System builds return an empty list.

Example usage:

 use Env qw( @PATH );
 
 unshift @PATH, Alien::MyLibrary->dynamic_dir;

=head2 alien_helper

 my $helpers = Alien::MyLibrary->alien_helper;

Returns a hash reference of helpers provided by the Alien module.
The keys are helper names and the values are code references.  The
code references will be executed at command time and the return value
will be interpolated into the command before execution.  The default
implementation returns an empty hash reference, and you are expected
to override the method to create your own helpers.

For use with commands specified in and L<alienfile> or in your C<Build.Pl>
when used with L<Alien::Base::ModuleBuild>.

Helpers allow users of your Alien module to use platform or environment
determined logic to compute command names or arguments in your installer
logic.  Helpers allow you to do this without making your Alien module a