Hi.
And I thought I understood python pretty well. Until I got hit by this:
>>> def f(x):
... print x
>>> cb = [lambda :f(what) for what in "1234"]
>>> for c in cb:c()
4
4
4
4
And even this works
>>> what = "foo"
>>> for c in cb:c()
foo
foo
foo
foo
I expected the output to be 1 2 3 4. Now I understand the cookbook
recipe for currying:
def curry(func, *args, **kwds):
def callit(*moreargs, **morekwds):
kw = kwds.copy()
kw.update(morekwds)
return func(*(args+moreargs), **kw)
return callit
cb = [curry(f,what) for what in "1234"]
gives the right functions.
Regards,
Igor
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