[Chris Barker] > ... > So what about: > > l = [x:=i for i in range(3)] > > vs > > g = (x:=i for i in range(3)) > > Is there any way to keep these consistent if the "x" is in the regular local scope?
I'm not clear on what the question is. The list comprehension would bind ` l ` to [0, 1, 2] and leave the local `x` bound to 2. The second example binds `g` to a generator object, which just sits there unexecuted. That has nothing to do with the PEP, though. If you go on to do, e.g., l = list(g) then, same as the listcomp, `l` will be bound to [0, 1, 2] and the local `x` will be left bound to 2. The only real difference is in _when_ the `x:=i for i in range(3)` part gets executed. There's no new twist here due to the PEP. Put a body B in a listcomp and any side effects due to executing B happen right away, but put B in a genexp and they don't happen until you force the genexp to yield results. For example, do you think these two are "consistent" today? l = [print(i) for i in range(3)] g = (print(i) for i in range(3)) ? If so, nothing essential changes by replacing "print(i)" with "x := i" - in either case the side effects happen when the body is executed. But if you don't think they're already consistent, then nothing gets less consistent either ;-)
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