alex23 <wuwe...@gmail.com> wrote: > keakon <kea...@gmail.com> wrote: > > def h2(x=[]): > > y = x > > y.append(1) > > return y + [] > > Are you aware that 'y = x' _doesn't_ make a copy of [], that it > actually points to the same list as x?
Sorry, I meant to suggest trying the following instead: def h2(x=None): if x is None: x = [] x.append(1) return x + [] It's a common idiom to use None as a sentinel for this situation, esp. where you _don't_ want a default mutable object to be reused. -- http://mail.python.org/mailman/listinfo/python-list
