Tim Peters <tim_one at email.msn.com>:
> If will if the "p" and "pipe" in the generator expression use the
> bindings in effect at the time the generator expression is assigned to
> pipe.
Lying awake thinking about this sort of thing last night,
I found myself wondering if there should be a way of
explicitly requesting that a name be evaluated at closure
creation time, e.g.
pipe = source
for p in predicates:
pipe = e for e in pipe if ^p(e)
where the ^ means that p is evaluated in the enclosing
scope when the closure is created, and bound to a slot
which behaves like a default-argument slot (but is
separate from the default arguments).
This would allow the current delayed-evaluation semantics
to be kept as the default, while eliminating any need
for using the default-argument hack when you don't
want delayed evaluation.
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 +--------------------------------------+
RetroSearch is an open source project built by @garambo | Open a GitHub Issue
Search and Browse the WWW like it's 1997 | Search results from DuckDuckGo
HTML:
3.2
| Encoding:
UTF-8
| Version:
0.7.4