{ccm} Add tracing feature

[asmaloney]

It would be useful to trace the changes in buffers as production rules fire.

As far as I can tell, right now this isn't possible "out of the box" without modifying ccm because we don't have a get() method on Buffer.

If we had that method, we could add something like this to the productions:

print('[start] goal: "' + str(goal.get()) + '" retrieve: "' + str(retrieve.get()) + '"')

to get some useful trace output:

[start] goal: "countFrom 2 5 counting" retrieve: "None"
2
[increment] goal: "countFrom 3 5 counting" retrieve: "count 2 3"
3
[increment] goal: "countFrom 4 5 counting" retrieve: "count 3 4"
4
[increment] goal: "countFrom 5 5 counting" retrieve: "count 4 5"
5
[stop] goal: "None" retrieve: "count 5 6"
end...

(Side note: I tried making a method trace() to be called for each production, but the way the ccm is implemented it doesn't seem to be possible. So it means outputting the print call directly at the end of each production.

[asmaloney]

Note that this is about the ccm framework. The other two output the trace by default.

[asmaloney]

ccm's logging may help here. Need to figure out if there are different levels, but just turning on logging in the amod file gives this which is a start:

ccm
---
   0.000 production initialRetrieval
   0.050 production None
   0.100 production chainCategory
   0.150 production None
   0.200 production directVerify
   0.250 production None
Yes
end...

[asmaloney]

Can now do this by adjusting the logging