Idiom for partial failures

[DL Neil]

On 21/02/20 10:05 AM, Stefan Ram wrote:
> David Wihl <davidwihl at gmail.com> writes:
>> I believe that it would be more idiomatic in Python (and other languages lik=
>> e Ruby) to throw an exception when one of these partial errors occur.
> 
>    I wonder whether the term "idiomatic" is too heavily
>    burdened here.
> 
>    Python offers an idiom for handling a failure to do an
>    operation - the exception.
> 
>    But you have special case of a run-time program of many
>    operations, and you want the execution of the program to
>    continue even in the case of failures to execute some of
>    the operations. I am not aware of Python offering an idiom
>    for this special case.
> 
>    I am always thinking about terminology first. So I'd say:
>    You need to /define/ what "success" and "failure" means in
>    the case of your operation. Then return normally in the case
>    of success and return by exception in the case of failure.


Not arguing - and if I were the logical answer is "not Python", but...

PyTest (runs unit-tests, enables TDD) offers options to stop the 
test-runner at the first error-found or to keep going for up to 
n-errors. We can test for an error condition and if experienced such 
will not 'count' or stop the test-run. It distinguishes between 
hard-errors and warnings, and enables us to choose to 'elevate' one to 
the level of the other, and vice-versa. Its run-report lists which tests 
worked and which didn't (the 'last' or the up-to "n") - a clear advance 
on the OP's experience.


I think someone has already discussed, but if the intent is 
bulk-processing ("batch processing") then I'd expect to find a means of 
'bailing-out' when an error is found, or of back-tracking to locate errors.

Perhaps, like my good-looks, my expectations of a professional standard 
are higher-than-average?
-- 
Regards =dn