[Python-Dev] docs - Copy (original) (raw)

Rich Healey healey.rich at gmail.com
Fri Jun 25 03:14:39 CEST 2010

On Fri, Jun 25, 2010 at 11:04 AM, Steve Holden <steve at holdenweb.com> wrote:

Rich Healey wrote:

http://docs.python.org/library/copy.html

Just near the bottom it reads: """Shallow copies of dictionaries can be made using dict.copy(), and of lists by assigning a slice of the entire list, for example, copiedlist = originallist[:]."""

Surely this is a typo? To my understanding, copiedlist = originallist[:] gives you a clean copy (slicing returns a new object....) Yes, but it's a shallow copy: the new object references exactly the same objects as the original list (not copies of those objects). A deep copy would need to copy any referenced lists, and so on.

My apologies guys, I see now.

I will see if I can think of a less ambiguous way to word this and submit a bug.

Thankyou!

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