possible python bug here

manuel manuelbastioniNOSPAM at tin.it
Sun Aug 29 17:10:44 CEST 2004


In the sample below, the foo function modify the b list,
but I think it should modify only c, not b! It work
correctly if if b is one dimension list instead two.

def foo(aList):
     print "use foo..."
     aList[2][0] += .35
     aList[2][1] += .35
     aList[2][2] += .35

p = [2.5,2.5,2.5]
b = [p,p,p,p]

c=b[:] #c is a totally new list cloned from b, it's not an alias!

print "b = ",b[2]

foo(c) #The argument is c, not b! Why b is modified too?

print "b = ", b[2]# after foo(c), the list b now is different!



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