Nuemark extension system

[thhck]

Is your feature request or improvement related to a problem?

I would like to compile RDF-a HTML from my markdown. So I can write:
my name is (name)[john doe]
and it compile to
<p>my name is <span property="name">john doe</span>

But I think this problem can be generalized to anyone wanting a special markdown syntax.

Solution you'd like

For example, Python's markdown library is extensible with a RDF-a module which make the lib compile a special RDF-a syntax. I think it's nice to be able to hack the compiler with custom regex ( the extenssion is only 100 lines of code long ) and let users the choice to opt-in for such features.

Alternatives you've considered

• Pre-compile with python markdown
• use Nuemark custom tag

Additional context