Connect multiple documentation sets together

[mvriel]

For release 3.1 or later, we are considering adding support for connecting multiple sets of documentation together. This means that if a library were to use phpDocumentor, that you can link that documentation to yours and whenever your documentation references a class in their project; a link would be made to that documentation site.

I want to gather more information, such as how to define such links, before starting an implementation. Two options I can think of already is to generate an XML index / sitemap to which you can refer your project to, or to define the links in your own project (but this is more cumbersome as the consuming project needs to maintain the links)

More input is appreciated during this RFC / Research phase.