OT: Addition of a .= operator

[Simon Ward]

On Wed, May 24, 2023 at 05:18:52PM +1200, dn via Python-list wrote:
>>Note that the line numbers correctly show the true cause of the
>>problem, despite both of them being ValueErrors. So if you have to
>>debug this sort of thing, make sure the key parts are on separate
>>lines (even if they're all one expression, as in this example), and
>>then the tracebacks should tell you what you need to know.
>
>
>Yes, an excellent example to show newcomers to make use of 'the 
>information *provided*' - take a deep breath and read through it all, 
>picking-out the important information...
>
>
>However, returning to "condense this into a single line", the 
>frequently-seen coding is (in my experience, at least):
>
>    quantity = float( input( "How many would you like? " ) )
>
>which would not produce the helpful distinction between 
>line-numbers/function-calls which the above (better-formatted) code 
>does!

Old thread I know, but thought it was worth pointing out that Python 3.11
brought in fine-graned error locations in tracebacks[1]:

    $ python3.10 asin.py
    Enter a small number: 4
    Traceback (most recent call last):
      File "/home/p10365088/asin.py", line 3, in <module>
        print(math.asin(float(input("Enter a small number: "))))
    ValueError: math domain error

    $ python3.11 asin.py
    Enter a small number: 4
    Traceback (most recent call last):
      File "/home/p10365088/asin.py", line 3, in <module>
        print(math.asin(float(input("Enter a small number: "))))
              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    ValueError: math domain error

[1]: https://docs.python.org/3/whatsnew/3.11.html#whatsnew311-pep657

Regards,
Simon
-- 
A complex system that works is invariably found to have evolved from a
simple system that works.—John Gall