If you could be a little more specific about what you are looking for,
we could provide a clearer answer.
The key distinction is: do you want to replace the textdatetime
plasmature type everywhere it is used, or do you simply want to have
at your fingertips an alternate version that is an extension, and
could be names something different?
If you want to do the former, I'd have to think for a while to
determine the best way to do that. It might require some changes to
how disco works to do it nicely.
If the latter, the answer is actually quite easy, since there is no
requirement that plasmature elements be defined inside the disco
directory.
1. Put a php file somewhere (it can be in reason_package_local if you
want, but it's not critical) and do the following things:
2. Include the base plasmature file.
3. Create a class that extends textdatetime and override any behavior
or markup that you wish
4. Whenever you want to use this new plasmature type, just include it
at the top of the file where you will be adding the element to disco.
Matt