Ensure main() catches all exceptions

[Pennycook]

Previously the exception handling was outside of main(), which meant that exceptions were only caught when codebasin was launched as a module (i.e., with python3 -m codebasin); the codebasin script generated by pyproject.toml did not catch exceptions.

Related issues

N/A

Proposed changes

• Add another level of indirection: main() calls _main() and catches all exceptions.

[laserkelvin]

It took me a second to understand the case, but I think I get it now.

I feel like _main and main naming can be confusing, despite being guilty of doing it myself in PyTorch somewhat frequently. Could we not just indent the entirety of main inside a try/except block instead?

[Pennycook]

I feel like _main and main naming can be confusing, despite being guilty of doing it myself in PyTorch somewhat frequently. Could we not just indent the entirety of main inside a try/except block instead?

We could indent the entirety of main, but then we'd have something like 8 levels of indentation in that function. The best solution would be to break things up into functions that can then be called by main(), which would also allow us to write unit tests for those functions. I'm thinking of this as a short-term fix to make sure we don't leak exceptions.