Example of Codex documentation for a Common Lisp library ยป Extending Codex

Codex, CommonDoc and Scriba were built with extensibility in mind. Here is an example I've published in the #poftheday post.

It adds a new type of node into the markup language:

POFTHEDAY> (common-doc:define-node twitter (common-doc:markup)
                                   ()
                                   (:tag-name "twitter"))

POFTHEDAY> (common-html.emitter::define-emitter (node twitter)
             (let* ((username (common-doc:text (first (common-doc:children node))))
                    (url (format nil "https://twitter/~A" username))
                    (name (format nil "@~A" username)))
               (common-html.emitter::with-tag ("a" node :attributes `(("href" . ,url)))
                                              (write-string name
                                                            common-html.emitter::*output-stream*))))

POFTHEDAY> (common-doc.format:parse-document *format* "Hello @ twitter(bob)!")
#<COMMON-DOC:DOCUMENT "">

POFTHEDAY> (pandocl:emit  * "hello.html")
#<COMMON-DOC:DOCUMENT "">

POFTHEDAY> (alexandria:read-file-into-string "hello.html")
"<!DOCTYPE html>
 <html>
    <head><title></title></head>
    <body>
       Hello <a href=\"https://twitter/bob\">@bob</a>!
    </body>
</html>"
NOTE1
I've intentionally added a space between character and twitter node name in the snippet abover, because there is a bug in the Scriba parser which does not allow to use unknown Scriba tags in the code snippets.
NOTE2
I've intended to add a sad "smile" at the end of the previos note, but seems Scriba doesnt' understand jokes.