Context-aware return

Sven R. Kunze srkunze at mail.de
Thu Sep 10 20:21:36 CEST 2015


I need to add: you need to look up the stack to see if you have been 
called by __main__ and if __main__.__file__ is missing.

Implementation: I would write decorator for your func.

Best,
Sven

PS: did I say it would probably be a bad idea? If not, it would probably 
be a bad idea.

PPS: what is the reason for this special behavior?

On 10.09.2015 20:03, Sven R. Kunze wrote:
> http://stackoverflow.com/questions/2356399/tell-if-python-is-in-interactive-mode 
>
>
>
> On 10.09.2015 19:54, Steven D'Aprano wrote:
>> I have a function which is intended for use at the interactive 
>> interpreter,
>> but may sometimes be used non-interactively. I wish to change it's 
>> output
>> depending on the context of how it is being called.
>>
>> If the function is being called as if it were a procedure or command, 
>> that
>> is the return result is just ignored, I want to return one thing. But 
>> if it
>> is being called where the return result goes somewhere, I want to return
>> something else. Most importantly, I don't want to pass a flag to the
>> function myself, I want the function to know its own context.
>>
>> I don't mind if it is CPython only, or if it is a bit expensive.
>>
>>
>> E.g.
>>
>> def func():
>>      do_stuff()
>>      if procedure:  # FIXME what goes here???
>>          return "Awesome"
>>      else:
>>          return 999
>>
>> Now I can do this:
>>
>>
>> x = func()
>> assert x == 999
>>
>> L = [1, 2, func(), 4]
>> assert L[2] == 999
>>
>> func()
>> # interactive interpreter prints "Awesome"
>>
>> Is such a thing possible, and if so, how would I do it?
>>
>> If I did this thing, would people follow me down the street booing and
>> jeering and throwing things at me?
>
> Probably. ;)
>
> But it it solve a problem, why not.
>
>
> Best,
> Sven



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