[IPython-dev] messaging protocol

Jason Grout jason-sage at creativetrax.com
Sat Apr 9 02:30:23 EDT 2011

On 4/8/11 4:43 AM, Thomas Kluyver wrote:
> On 8 April 2011 09:04, Jason Grout <jason-sage at creativetrax.com
> <mailto:jason-sage at creativetrax.com>> wrote:
> I was thinking more of multiple output messages for a single input
> (assuming that you stored multiple outputs in the database).  That
> is our current problem, since our use-case will always have an
> execution_count of 1.
> At present, if you get multiple outputs (e.g by doing "12*3; 88*14",
>  they are stored in a JSON list in the database (if you have output
> logging enabled, which it isn't by default).
> I'm not quite sure what you mean by always having an execution count
> of 1. Is this the aleph prototype* or something similar?

That's exactly what it is: an extension of the aleph idea [1].  Ira 
Hanson and I are working on moving the communication over to use the 
ipython messaging protocol.

> The way I envisaged history working, if the namespace is preserved
> from command to command, the execution count increases. If it isn't,
> each run is kind of a new session. The interface for retrieving
> history works better with sessions with more than one command, but
> there's nothing to stop you making sessions with a single cell in
> each.

Interesting.  So execution count really is just a counter on executions 
where the namespace is preserved.  What do you mean by "namespace is 
preserved"?  How do you test for it?



[1] The codebase is here: 
http://code.google.com/p/simple-python-db-compute/ (see our various 
clones of it as well).  The design/todo list is here: 

More information about the IPython-dev mailing list