Suggested python feature: allowing except in context maneger

[Yair Eshel via Python-list]

Hello. I read this is a good place to give some suggestions for features in
python. If not, please let me know.

This is an example of a code I normally use in my everyday work:
import logging
try:
  with open('sample_data/READM.md') as f:
print (len(f.read()))
except FileNotFoundError:
  logging.error("File not found")


As you can see I have 2 levels of indentation, which can add some pain to
the work with the context manager. This code without context manager, can
be replaced by this code:

import logging
try:
  f = open('sample_data/READM.md') as f:
  print (len(f.read()))
except FileNotFoundError:
  logging.error("File not found")
finally:
  f.close()

And while this offers less indentations, it skips the usage of the very
handy context manager.

I would like to suggest an alternative syntax, that will, in a sense, apply
the best of both worlds:

import logging
with open('sample_data/README.md') as f:
  print (len(f.read()))
except FileNotFoundError:
  logging.error("File not")

As "with" applies the behavior of the "try / finally" it feels like a
natural part of this syntax. This could provide a cleaner code.
If this idea is accepted, there are several things that need to be
discussed, like what to do with "else" or "finally" statement following a
context manager. I'm not sure about the proper way to handle this.

With hopes for an even more readable future
Yair
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Re: Suggested python feature: allowing except in context maneger

[Yair Eshel via Python-list]

Cameron, I'm not really sure I got your point. I've used the "file not
found" exception as an example for a behavior typical on context managers.
This could be a failure to connect to DB, or threads. It also applies to
any kind of possible exception, whether cased by the context manager itself
or the lines inside it. Long story short, this syntax change is as useful
as context managers are

On Fri, 14 Jun 2024, 01:49 Cameron Simpson,  wrote:

> On 13Jun2024 19:44, dieter.mau...@online.de 
> wrote:
> >Why not use:
> >```
> >try:
> >  with open()...
> >...
> >except FileNotFoundError:
> >  ...
> >```
>
> This is exactly what the OP was expressing dissatisfaction with.
>
> I'm -1 on the idea myself - not every combination of things needs
> additional syntactic support, and doing stuff like merging an `except`
> with a `wtih` is bound to introduce some weird corner case, complicating
> its semantics.
>
> Cheers,
> Cameron Simpson 
>
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