I don't think that's what Leonardo was getting at, but rather that if you have to support python semantics, at some point you've got to deal with that overhead. For example, you have to do bounds checking on all list subscription, because javascript won't raise exceptions for you in that case.
yep. we have an emulation-implementation of list, dict and tuple that raise an appropriate javascript exception that's given the same name as the python one. additionally, flier liu, who wrote pyv8, has written some code into PyV8 that allows the transfer of exceptions between a python context and a javascript context. i believe he's only done it one-way so far. ... ok - actually, you're right: looking at pyjslib.py more closely, the only compliance with python exceptions is KeyError in the emulation-implementation of dict, which at least demonstrates the principle. so, one for the TODO list, then :) hmm, i should add some tests. l.