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I occasionally see the list slice syntax used in Python code like this:
newList = oldList[:] Surely this is just the same as:
newList = oldList Or am I missing something?
Like NXC said, Python variable names actually point to an object, and not a specific spot in memory.
newList = oldListwould create two different variables that point to the same object, therefore, changingoldListwould also changenewList.However, when you do
newList = oldList[:], it ‘slices’ the list, and creates a new list. The default values for[:]are 0 and the end of the list, so it copies everything. Therefore, it creates a new list with all the data contained in the first one, but both can be altered without changing the other.