M Bfmv writes:
> ```
> if [i for i in range(10) if i == 11]:
> print(this)
>
> Evaluate: []
> ```
This usage of 'this' in that code is called "anaphora". It's very
useful in natural language and most (all? :-) natural languages have
it, but in a programming language it requires a convention (that must
be learned and remembered by anyone who reads your code, including
last year's lint programs!) and either requires reserving the
conventional identifier (in your case, 'this') or creating ambiguity
when some programmer uses it for something else. Some programming
languages have it. Python has preferred to avoid it.
The assignment operator (aka "walrus operator") that others have
pointed out is a good compromise IMO:
if this := [i for i in range(10) if i == 11]:
print(this)
Of course the walrus operator is very new and has the same burden on
human readers and linters, but it's far more flexible and useful than
the implicit use of anaphora. I think the addition of the walrus
operator means there will be no anaphora in Python ever.
Steve
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