Hello NG,
I am wondering if there were proposals or previous disscussions in this
NG considering using 'while' in comprehension lists
# pseudo code
i=2
lst=[i**=2 while i<1000]
of course this could be easily rewritten into
i=2
lst=[]
while i<1000:
i**=2
lst.append(i)
usually I would prefer one liners like
lines=[line.strip() for line in file("foo").readlines() if line]
they make the purpose clear
so if 'while' were allowed in comprehension list this would allow
to write concise code
to the example above, I tried a workaround
i=2
lst=[i**=2 for _ in iter(lambda:_<1000, False)]
but this failes with SyntaxError because of i**=2
and must be also rewritten into
>>> i=2
>>> def f():
... global i
... i**=2
... return i
...
>>> lst=[f() for _ in iter(lambda:i<1000, False)]
>>> lst
[4, 16, 256, 65536]
I think this loses compared with
i=2
lst=[i**=2 while i<1000]
Regards, Daniel
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