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No, spamizbad is correct that wahnfrieden's comment was insightful. List and tuple have totally different semantics; they also happen to differ in mutability wh

No, spamizbad is correct that wahnfrieden's comment was insightful. List and tuple have totally different semantics; they also happen to differ in mutability which just confuses the issue unfortunately.

klibertp 13y ago
I'm not that sure about "totally different" semantics; in Python lists and tuples happen to share quite a lot of public interface. As they both are heterogeneous by default (in Python), I disagree with this being their biggest difference. It's not a case in OCaml or Erlang, where lists and tuples differ significantly in both interface and complexity of basic actions. For example, what is a computational complexity of getting nth element of tuple and list in Python, and why it's exactly the same for both of them? In Erlang, where lists are real lists, getting nth element is O(n) in case of lists and O(1) in case of tuples. In Python, lists and tuples mean almost exactly the same thing. That's how Python is implemented. Those two things have "totally different" semantics in many other languages, not so in Python. As so, using the one over the other in many cases is purely stylistic matter, not the matter of semantics... unless it's about mutability, of course. If they're as different as you and grandparent suggest, then please list those differences, and mean in Python. As I said, in OCaml Lists and tuples are completely different types, starting with the fact that tuples are not iterables (!). The same is true in Erlang, where you need to explicitly convert a tuple to list to get all the elements of a tuple. Both list and tuple are iterable in Python, however. I just see much more similarities between lists and tuples in Python than differences, to the point that I wouldn't mind calling tuples an immutable_list or frozenlist, or something like that.
- Myrmornis 13y ago
  This was best and most succinctly stated by wahnfrieden: tuples are appropriate where a named-tuple could also conceivably be used.

klibertp 13y ago

I'm not that sure about "totally different" semantics; in Python lists and tuples happen to share quite a lot of public interface. As they both are heterogeneous by default (in Python), I disagree with this being their biggest difference. It's not a case in OCaml or Erlang, where lists and tuples differ significantly in both interface and complexity of basic actions. For example, what is a computational complexity of getting nth element of tuple and list in Python, and why it's exactly the same for both of them? In Erlang, where lists are real lists, getting nth element is O(n) in case of lists and O(1) in case of tuples. In Python, lists and tuples mean almost exactly the same thing. That's how Python is implemented. Those two things have "totally different" semantics in many other languages, not so in Python. As so, using the one over the other in many cases is purely stylistic matter, not the matter of semantics... unless it's about mutability, of course. If they're as different as you and grandparent suggest, then please list those differences, and mean in Python. As I said, in OCaml Lists and tuples are completely different types, starting with the fact that tuples are not iterables (!). The same is true in Erlang, where you need to explicitly convert a tuple to list to get all the elements of a tuple. Both list and tuple are iterable in Python, however. I just see much more similarities between lists and tuples in Python than differences, to the point that I wouldn't mind calling tuples an immutable_list or frozenlist, or something like that.

Myrmornis 13y ago
This was best and most succinctly stated by wahnfrieden: tuples are appropriate where a named-tuple could also conceivably be used.