The only differences are that tuples are immutable and that lists have extra methods.
Is there ever a strong need for list-type data to be immutable? Evough to justify a whole extra data-type in the language?
Should they release a python 4 with it removed?
The only thing I can think of is as a default function parameter. This function is okay:
def dothings(a=(1,2)):
print(a)
a = (a[0], 3)
But this function misbehaves the second time it is called:
def dothings(a=[1,2]):
print(a)
a[1] = 3
But IMO the “mutable arguments” thing is another bug to be fixed in a hypothetical python 4. And even in python 3 you just write the function the recommended way, so there is not such a big problem.
def dothings(a=None):
if a is None:
a = [1, 2]
print(a)
a[1] = 3
The Python devs are clever guys though. There must be some really important reason to maintain both types?
This could be the right answer. I know tuples use slightly less memory. But I’m not if that’s so important. I don’t think programs ever need to iterate over 1 million tuple entries, where speed or memory would be important.
One important reason why tuples exist is that unlike lists they are immutable. So they are hashable and can be used as keys in dictionaries among other things.