CPAN links

In the Perl world CPAN is the source of modules. To search for a module, sites like search.cpan.org help a lot.

Now, when mentioning a Perl module in your document, it makes sense to give direct access to the package. Given that each distribution A::Dist can be found under a link http://search.cpan.org/dist/A-Dist (with all double colons in a package name replaced by hyphens), in PerlPoint we can write

   ... the distribution
   \L{url="http://search.cpan.org/dist/PerlPoint-Package"}<PerlPoint::Package> ...

To open the link in a new window, this could be extended to

   ... the distribution
   \L{url="http://search.cpan.org/dist/PerlPoint-Package" target=_blank}<PerlPoint::Package> ...

which is a fairly long expression. For a typical Perl text mentioning lots of modules this is a lot of overhead - but it can be reduced significantly by a macro.

As we have to do a substitution this macro will use embedded Perl. Here is an suggestion (remove the newlines when copying):

    +CPAN:\EMBED{lang=perl}
             (my $b='__body__')=~s/::/-/g;
             qq(\XO<__body__>\C<\L{url="http://search.cpan.org/dist/$b/" target=_blank}<__body__>>);
          \END_EMBED

The macro does all the necessary work: it substitutes double colons by hyphens and constructs a link to the distribution page that opens in a new window. Additionally, it formats the module name as code and transparently adds an index entry for it.

With this definition, now a module can be mentioned quickly:

    ... the distribution \CPAN<PerlPoint::Package> ...

The only restriction is that the PerlPoint converter runs with option -active to enable Active Contents, otherwise embedded Perl (and thus the \CPAN macros) will be ignored.