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 );

From Makefile.PL (static with wrapper)

 use Alien::Base::Wrapper qw( WriteMakefile);
 
 WriteMakefile(
   'NAME'              => 'Foo::XS',
   'VERSION_FROM'      => 'lib/Foo/XS.pm',
   'alien_requires'    => {
     'Alien::Foo' => 0,
     'Alien::Bar' => 0,
   },
 );

From Makefile.PL (dynamic):

 use Devel::CheckLib qw( check_lib );
 use ExtUtils::MakeMaker 6.52;
 
 my @mm_args;
 my @libs;
 
 if(check_lib( lib => [ 'foo' ] )
 {
   push @mm_args, LIBS => [ '-lfoo' ];
 }
 else
 {
   push @mm_args,
     CC => '$(FULLPERL) -MAlien::Base::Wrapper=Alien::Foo -e cc --',
     LD => '$(FULLPERL) -MAlien::Base::Wrapper=Alien::Foo -e ld --',
     BUILD_REQUIRES => {
       'Alien::Foo'           => 0,
       'Alien::Base::Wrapper' => 0,
     }
   ;
 }
 
 WriteMakefile(
   'NAME'         => 'Foo::XS',
   'VERSION_FROM' => 'lib/Foo/XS.pm',
   'CONFIGURE_REQUIRES => {
     'ExtUtils::MakeMaker' => 6.52,
   },
   @mm_args,
 );

=head1 DESCRIPTION

This module acts as a wrapper around one or more L<Alien> modules.  It is designed to work
with L<Alien::Base> based aliens, but it should work with any L<Alien> which uses the same
essential API.

In the first example (from the command line), this class acts as a wrapper around the
compiler and linker that Perl is configured to use.  It takes the normal compiler and
linker flags and adds the flags provided by the Aliens specified, and then executes the
command.  It will print the command to the console so that you can see exactly what is
happening.

In the second example (from Makefile.PL non-dynamic), this class is used to generate the
appropriate L<ExtUtils::MakeMaker> (EUMM) arguments needed to C<WriteMakefile>.

In the third example (from Makefile.PL dynamic), we do a quick check to see if the simple
linker flag C<-lfoo> will work, if so we use that.  If not, we use a wrapper around the
compiler and linker that will use the alien flags that are known at build time.  The
problem that this form attempts to solve is that compiler and linker flags typically
need to be determined at I<configure> time, when a distribution is installed, meaning
if you are going to use an L<Alien> module then it needs to be a configure prerequisite,
even if the library is already installed and easily detected on the operating system.

The author of this module believes that the third (from Makefile.PL dynamic) form is
somewhat unnecessary.  L<Alien> modules based on L<Alien::Base> have a few prerequisites,
but they are well maintained and reliable, so while there is a small cost in terms of extra
dependencies, the overall reliability thanks to reduced overall complexity.

=head1 CONSTRUCTOR

=head2 new

 my $abw = Alien::Base::Wrapper->new(@aliens);

Instead of passing the aliens you want to use into this modules import you can create
a non-global instance of C<Alien::Base::Wrapper> using the OO interface.

=head1 FUNCTIONS

=head2 cc

 % perl -MAlien::Base::Wrapper=Alien::Foo -e cc -- cflags

Invoke the C compiler with the appropriate flags from C<Alien::Foo> and what
is provided on the command line.

=head2 ld

 % perl -MAlien::Base::Wrapper=Alien::Foo -e ld -- ldflags

Invoke the linker with the appropriate flags from C<Alien::Foo> and what
is provided on the command line.

=head2 mm_args

 my %args = $abw->mm_args;
 my %args = Alien::Base::Wrapper->mm_args;

Returns arguments that you can pass into C<WriteMakefile> to compile/link against
the specified Aliens.  Note that this does not set  C<CONFIGURE_REQUIRES>.  You
probably want to use C<mm_args2> below instead for that reason.

=head2 mm_args2

 my %args = $abw->mm_args2(%args);
 my %args = Alien::Base::Wrapper->mm_args2(%args);

Returns arguments that you can pass into C<WriteMakefile> to compile/link against.  It works
a little differently from C<mm_args> above in that you can pass in arguments.  It also adds
the appropriate C<CONFIGURE_REQUIRES> for you so you do not have to do that explicitly.

=head2 mb_args