[Python-Dev] cpython: Rename contextlib.ignored() to contextlib.ignore(). (original) (raw)

R. David Murray rdmurray at bitdance.com
Wed Oct 16 16:36:04 CEST 2013

Victor Stinner <victor.stinner at gmail.com> a écrit :

I might agree with idea of contextlib.ignore() (I'm still opposed to the idea), but I don't understand the purpose of adding a new syntax doing exactly the same than try/except:

> with trap(OSError) as cm: > os.unlink('missing.txt') > if cm.exc: > dosomething() Nobody noticed that this can be written: try: os.unlink('missing.txt') except OSError as err: # do something with err ?? What happened with the Zen Principle "There should be one-- and preferably only one --obvious way to do it." I don't understand why I would import contextlib and use a new context manager, whereas try/except is already a builtin feature of Python.

For the record, that was not my proposal. You'd be silly to replace the try/except with the context manager in the above case. The case where the CM would be useful would be if there were statements in between the context manager and the 'if'.

And that still wasn't the proposal. My proposal was to provide the exception on the CM so that the name 'trap' made sense, and so that it was clear that only one exception was ever caught, and so that the CM was parallel in functionality to the existing assertRaises CM.

But none of this affects the code, because Nick isn't accepting the proposal, and that's fine.

--David

More information about the Python-Dev mailing list