Why does var type change when unpacking a tuple?

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Consider this example:

>>> t = (1, 2, 3)
>>> a, b, c = t
>>> a, b, c
(1, 2, 3)
>>> a, *b = t
>>> a, b
(1, [2, 3])

Why do I get a list instead of a tuple when unpacking a tuple with a, *b = t ?

9. Tuples — How to Think Like a Computer Scientist: Learning with , So if julia has a new recent film, we could change her variable to reference a new tuple that used some One way to think of tuple assignment is as tuple packing/ unpacking. meaning that it can be composed of elements of different types. Once we have this ‘packed’ variable, we can do things with it that we would with a normal tuple. args[0] and args[1] would give you the first and second argument, respectively. Since our tuples are immutable, you can convert the args tuple to a list so you can also modify, delete and re-arrange items in i. Packing and Unpacking

You can find more information in this link https://www.python.org/dev/peps/pep-3132/ but I think it's essentially because this is generic iterable unpacking so it converts things to a list first to handle for the generic case:

Also, if the right-hand value is not a list, but an iterable, it has to be converted to a list before being able to do slicing

I think tuple is a special case where the implementation could allow for it returned as a tuple, since tuples already allow slicing but it looks like the decision was made to implement the most generic version in this case.

Unpacking a Tuple in Python, Python Tuples In python tuples are used to sore immutable object. In other way it is called unpacking of a tuple of values into a variable. we extract those values into a single variable. Example 1. filter_none. edit close print type of college. This is because the first bytecode in the function literally translates into the tuple argument being unpacked. Assuming the tuple parameter is named .1 and is expected to unpack to variables spam and monty (meaning it is the tuple (spam, monty)), the first bytecode in the function will be for the statement spam, monty = .1.

In Python 3.0, the * operator was added to the multiple assignment syntax, allowing us to capture remaining items after an unpacking into a list. The * operator allows us to replace hard-coded slices near the ends of sequences.

Arccording your code:

>>> t = (1, 2, 3)
>>> a, b, c = t
>>> a, b, c
(1, 2, 3)
>>> a, *b = t
>>> a, b
(1, [2, 3])

The same code:

>>> t = (1, 2, 3)
>>> a, b, c = t
>>> a, b, c
(1, 2, 3)
>>> a, *b = t[0], t[1:]
>>> a, b
(1, [2, 3])

Read more here.

Multiple assignment and tuple unpacking improve Python code , Multiple assignment is often called “tuple unpacking” because it's Note that on that last line we're actually swapping variable names, which is something multiple With the * operator and multiple assignment you can replace things like this Note that in this second case, it's much more clear what type of� var sum = 4.5; var count = 3; var t = (sum, count); Console.WriteLine($"Sum of {t.count} elements is {t.sum}."); That's known as tuple projection initializers. The name of a variable isn't projected onto a tuple field name in the following cases: The candidate name is a member name of a tuple type, for example, Item3, ToString, or Rest.

13.3. Tuple Assignment with Unpacking — Foundations of Python , Not logged in; Assignments � Practice � Change Course � Instructor's Page � Progress Page � Edit Profile � Change Unpacking into multiple variable names also works with lists, or any other sequence type, as long as there is exactly one value for each variable. You can unpack each tuple into several loop variables. When we use *args syntax in a function call, we are unpacking the variable. By unpacking, we mean that we are pulling out the individual values of the list. In this case, we pull out each element of the list and place them in the arguments, where position 0 corresponds to the first argument. You can also similarly unpack a tuple:

Unpacking in Python: Beyond Parallel Assignment, Each variable in the tuple can receive one value (or more, if we use the We can form a stared expression using the unpacking operator, * , along with a valid In this case, since we're using unpacking in Python, no changes are needed for� Tuple unpacking. One thing to note is that even though these two variables are of different data types, Python allows us to assign these variables with other data types (e.g. for the variable a

Unpacking a Tuple in Python, In this article, we will learn about packing an unpacking tuple type in Python is known as unpacking of a tuple of values into a norml variable. For tuple, it could be done exactly same to list, and for dict, just use ** instead of *. And there is also one more type of unpacking, it is not for function but just unpack the list or tuple