list as paremeters...

[Mel Wilson]

In article <bislss$ckt13$1 at ID-67890.news.uni-berlin.de>,
"Ulrich Petri" <ulope at gmx.de> wrote:
>IIRC Default values are not created each time the function called but rather
>only the first time (am i correct here?). And since a list is mutable it
>"rememberes" the previous value.

   Default values are created when the 'def' statement is
executed, for example:


def f1 (t, usual=[]):
    usual.append (t)
    print 'F1:', usual

for x in [1, 2, 3, 4, 5]:
    def f2 (t, usual=[]):
        usual.append (t)
        print 'F2:', usual

    f1 (x)
    f2 (x)


Results in


F1: [1]
F2: [1]
F1: [1, 2]
F2: [2]
F1: [1, 2, 3]
F2: [3]
F1: [1, 2, 3, 4]
F2: [4]
F1: [1, 2, 3, 4, 5]
F2: [5]


        Regards.        Mel.