[Python-ideas] Possible PEP 380 tweak
greg.ewing at canterbury.ac.nz
Sat Oct 30 01:30:54 CEST 2010
Guido van Rossum wrote:
> I went over that myself in detail and ended up deciding that for
> "yield-from" nothing should be changed! The expansion in the PEP
> remains the same.
In that case, the proposal has nothing to do with PEP 380
and needn't be mentioned in it -- except perhaps to point
out that using it in the presence of yield-from may
not produce the expected result.
> But since this PEP also specifies "return value" it would be nice if
> there was a convenient way to capture this value,
As long as you're willing to accept that if the generator
you're closing is delegating using yield-from, the return
value from the inner generator will get lost.
To put it another way, if you design a generator to be
used in this way (i.e. its caller using close() to finish
it and get a value), you may find it awkward or impossible
to later refactor it in certain ways.
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