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[Python-Dev] accumulator display syntax

Greg Ewing greg at cosc.canterbury.ac.nz
Sun Oct 19 20:34:54 EDT 2003 
Sean Ross <seandavidross at hotmail.com>:

> # (1) without parentheses:
> B(y) for y in A(x) for x in myIterable

Er, excuse me, but that had better *not* be equivalent to

> # (2) for clarity, we'll add some optional parentheses:
> B(y) for y in (A(x) for x in myIterable)

because the former ought to be a single iterator expression
with two nested loops (albeit an erroneous one, since x
is being used before it's bound).

Greg Ewing, Computer Science Dept, +--------------------------------------+
University of Canterbury,	   | A citizen of NewZealandCorp, a	  |
Christchurch, New Zealand	   | wholly-owned subsidiary of USA Inc.  |
greg at cosc.canterbury.ac.nz	   +--------------------------------------+
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