org-block-begin-line allows to customize the first line of the following block
#+BEGIN_SRC lang :var arg1=1 arg2=2 ... #+END_SRC
However, I would like to customize the faces within the line, by highlighting the
lang, and certain properties, like highlighting only
Digging further, we can see that the use of the face is done within
(org-fontify-meta-lines-and-blocks-1). But nothing there seems to allow to split the line in several blocks, and even less by doing it conditionally.
Something similar was proposed by rasmus ( https://pank.eu/blog/pretty-babel-src-blocks.html ) to implement further modification on the line, but this is not quite what I am looking for.
Might there be a package already available out there to add some colors // apply some regexp on this line ?
Also, it might be interesting if the same rules could apply on an inline
src_lang() and a
#+CALL: type of line.