I'm not able to understand the mechanism behind this behavior in python.
def fun(s=[]):
s.append(1)
print s
fun()
fun()
Output is:
[1]
[1,1]
Why does python "remember" the value of the list passed on the function?
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siddharth iyer
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`Actually, this is not a design flaw, and it is not because of internals, or performance. It comes simply from the fact that functions in Python are first-class objects, and not only a piece of code.` – cs95 Oct 31 '17 at 05:54
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This is explained here: http://docs.python-guide.org/en/latest/writing/gotchas/#mutable-default-arguments – Sharad Oct 31 '17 at 05:56