Python Macros

[Michael Sparks]

Arich Chanachai wrote:

> How hard/easy is it to extend the Python syntax? 

It's not that hard to do, but involves changing the compiler and if done
properly a whole slew of other things. If you want non-functional syntax
changes it's fairly trivial - just change the Grammar file and rebuild. 
If you want a checklist of things you might want to look at when changing
the syntax you could look at this patch : http://www.python.org/sf/1013835

It's worth noting that this would probably result in a local overhead for
yourself in maintaining a private branch of python however - since this
changes your python in a fairly fundamental manner. I don't know what your
use case is though - if it's experimentation then I suspect that you'd be
happy with that :)

> Perhaps there are macro facilities for this? 

Not that I'm aware of. (At least not as far as I know in the lisp or C
meanings of the term)

> I'd like to add messages and message passing, for example.

Why do you feel you need to extend the language for this? Why not (for
example) overload <<, >> and similar operators? __lshift__, __rshift__ etc.
I'd really recommend not extending the language unless you really don't have
any option - unless that's what you're specifically interested in :)

Regards,


Michael.