fs=[]
fs = [(lambda n: i + n) for i in range(10)]
[fs[i](1) for i in range(10)]
[10, 10, 10, 10, 10, 10, 10, 10, 10, 10] <=== not good
( that was a big surprise! . . . )
( let's try it another way . . . )
fs =[]
def g(i): return (lambda n: i + n)
fs = [g(i) for i in range(10)]
[fs[i](1) for i in range(10)]
[1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
(aaah, that's better . . . )
(hmmm, let's try another . . . )
fs =[]
for i in range(10):
fs.append(lambda n, i=i: i + n)
[fs[i](1) for i in range(10)]
[1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
(aaaah, that works too . . . )
(... and another... )
fs=[]
fs = [(lambda n, i=i: i + n) for i in range(10)]
[fs[i](1) for i in range(10)]
[1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
(great! . . . )
(now then, what's wrong with this picture ?)
lambda? closure? scope? bug?
What is going on with the binding in the first construct... this
seems to reduce the usefulness of lambda to a considerable extent?
kind regards,
m harris
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