[BangPypers] Python Gotcha Fibonacci

[Rajiv Subramanian M]

Hi Group,

I just went through this article
http://docs.python-guide.org/en/latest/writing/gotchas/

written a Fibonacci program like this

def fibonacci(next=[1], prev=[0]):
    data = prev.pop()
    prev.append(next.pop())
    next.append(prev[0] + data)
    return data

for i in range(10):
    print fibonacci()

It actually works, it prints first 10 fibonacci numbers

My question is the following code doesn't work the same way as i expected
it to work.

def fibonacci(next=1, prev=0):
    data = prev
    prev = next
    next = data + next
    return data

for i in range(10):
    print fibonacci()

Instead of printing Fibonacci, it just prints 10 zeros

means.. does python only remembers the list in default argument?

-- 

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Rajiv Subramanian M
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