[O] Custom export backend based on HTML: how to implement own blocks?

[Marcin Borkowski]

Hello,

I'd like to (ab)use the "underline" syntax for something else.
Basically, I'd like to translate

_underlined_

to

<span class="my-own"><variant>underlined<variant></span>

and

_underlined|with variant_

to

<span class="my own"><variant>underlined</variant><variant>with
variant</variant></span>

but only if the underlining is between

#+BEGIN_MYBLOCK
...
#+END_MYBLOCK

How to achieve this?  In particular, I'd like to know:

1. How can I know (in org-html-underline, for instance) whether I am in
a MYBLOCK or not?

2. How do I best translate the "|" syntax into "variants"?  More
specifically: is it a good idea to do it in org-my-html-underline, by
analysing the "underlined" text (as a string) or maybe it's better to
write a filter?  (I guess the former idea is better.)

Best,

-- 
Marcin Borkowski
http://octd.wmi.amu.edu.pl/en/Marcin_Borkowski
Faculty of Mathematics and Computer Science
Adam Mickiewicz University