BEGIN {
    package MY;

    use File::Spec::Functions qw( catdir catfile );

    sub init_PM {
        my $self = shift;

        $self->SUPER::init_PM(@_);

        my @path = qw( ... );
        my $src_base = catdir('lib', @path);
        my $dst_base = join('$(DIRFILESEP)', '$(INST_LIB)', @path);

        for (...) {
            my $src = catfile(              $src_base, "$_.pm");
            my $dst = join('$(DIRFILESEP)', $dst_base, "$_.pm");
            $self->{PM}{$src} = $dst;
        }
    }
}