But `finally` with a `for` loop is redundant since the code can be placed just after the loop. For `try/except` it's a different situation since the exception might bubble up, so "normal" code after the `try` won't be reached.
Also `on_break` doesn't seem really important since that code can be executed inside the loop right before the `break`.
We already have `else` for `on_finish` and I think when recalling the analogy to exceptions it's not that confusing: a `try` block can be exited either normally (because all code has been executed) or because it raised an exception; here `else` means it exited normally. Similarly a `for` loop can terminate either normally by executing all iterations or because a `break` occurred; and similarly `else` means it terminated normally.
On 15.07.20 08:47, Mathew Elman wrote:
But in `for...else` the `else` call isn't always called, so changing `else` for `finally` doesn't make sense. What you're suggesting is replacing`else` with `on_finish` and adding `finally` and`on_break`.
I agree that having `finally` could make the use cases of `else` clearer, but I am not convinced renaming "else" to "on_finish" would help the confusion for the 0 iteration case.
I think that since this suggestion doesn't help with the 0 iteration case (my first idea here didn't either), it feels like added extra compound statements need to be immediately intuitive to be worth having - either because they read like a sentence or parallel existing python e.g. `try-except-else-finally` or `if-elif-else` etc.
On Wed, 15 Jul 2020 at 06:47, Steve Barnes <GadgetSteve@live.co.uk mailto:GadgetSteve@live.co.uk> wrote:
Can I suggest that for loops the `else` would be a lot clearer if it was spelt `finally` as was done for PEP-0341 for try blocks and that we might possibly need one or more `on_…` clauses such as `on_break` and `on_finish` I think that this would be a lot clearer: for i in range(N): if i > 3: break; on_break: # Called if loop was broken print(i) on_finish: # Called if loop was not broken print("Loop Completed") finally: # Always called (replaces for…else) print("Loop Ended") Which I think would be a lot easier for newcomers to learn than try…for…else…except…else e.g.: try: for i in range(N): if i > 3: break; elif i % 2 == 0: raise ValueError("Odds Only"); else: # to if print(i) else: # Else to loop print("Loop Completed") except ValueError as err: print(err) else: # to try print("No Exception") finally: print("Try Ended") Where the multitude of elses makes my eyes cross. Steve Barnes _______________________________________________ Python-ideas mailing list -- firstname.lastname@example.org <mailto:email@example.com> To unsubscribe send an email to firstname.lastname@example.org <mailto:email@example.com> https://mail.python.org/mailman3/lists/python-ideas.python.org/ Message archived at https://firstname.lastname@example.org/message/MKAAWV6OT7SRIHTDOAEA3OHV6ZLSGLE2/ Code of Conduct: http://python.org/psf/codeofconduct/
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