What I am looking for in the blockchain is that code was executed without error. For example, if the code that was executed is code that verified the existence of a transaction in the bitcoin blockchain, this mechanism can be used to step through the cross chain algos.
Okay - well in that case why not make your "prototype" plugin check for the existence of a Bitcoin transaction instead (that has at least x confirmations)?
The "script" will have "state" so any "plugin calls" it makes would presumably have some sort of "return value" that could be checked and/or kept in the script's state.
I didnt think there was a chance to find bitcoind in Java form that jean-luc would consider adding to NXT core.
It is MUCH simpler to solve the issues with a hardcoded NXTplugin since we dont have to deal with Evil Bob changing the executable. Not having to worry about Evil Bob seemed prudent for the first attempt at adding parsing of AM data to see what plugins to call, etc.
If we cant solve the issue with simple hardcoded plugin, no chance for complex external plugin. That is why I chose email as the proof of concept.
Also, for testing, it will be much more nervous if it was bitcoin transactions for the first attempt at plugin. Doing this step was a couple miniprojects down the road. Believe it or not, I am pacing myself!
James