[Python-ideas] Revised**6 PEP on yield-from

Mon Feb 23 14:05:09 CET 2009

Given that the expansion is quite complicated...
Imagine that we want to alter the values while passing them from the
inner generator. For example:
 for x in expr:
 yield x+1
How to let this be as transparent to send/close/etc. as yield from?
If the transformation is an expression, one can use a generator comprehension:
 yield from (x+1 for x in expr)
but this does not work if we have some statements inside:
 seen = set()
 for x in expr:
 if x not in seen:
 seen.add(x)
 yield x
(I'm not familiar with the details of how send works, but I hope the
point is valid.)
-- 
Marcin Kowalczyk
qrczak at knm.org.pl
http://qrnik.knm.org.pl/~qrczak/