[Tutor] UPDATE: Is there a 'hook' to capture all exits from a python program?

[Peter Otten]

Albert-Jan Roskam wrote:

>>I would expect that
>>
>>try:
>>main program here
>>finally:
>>close_relay()
> 
> Is this (also) called a diaper pattern? 

Cool name, but most parents want the baby's faeces to go into the diapers 
whereas try ... bare except is notorious for swallowing useful information 
that should be propagated to the user or developer.

> Or is that name reserved for the
> antipattern with try-bare except, where the 'except' catches all the sh*t
> (pardon my language)?

For try ... finally it's its raison d'être to execute some code no matter 
what. E. g. before the advent of with ...

with open(...) as f:
    ... # use file
# file is closed now even if something went wrong while using it and no
# matter how garbage collection works for the Python implementation running
# the code.
# The exception (if any) is not swallowed

it was good style to write

f = open(...)
try:
    ... # use file
finally:
    f.close()
# file is closed...