What is scheme's equivalent of tuple unpacking?

Question

In Python, I can do something like this:

t = (1, 2)
a, b = t

...and a will be 1 and b will be 2. Suppose I have a list \'(1 2) in

Answer 1

In racket you can use match,

(define t (list 1 2))
(match [(list a b) (+ a b)])

and related things like match-define:

(match-define (list a b) (list 1 2))

and match-let

(match-let ([(list a b) t]) (+ a b))

That works for lists, vectors, structs, etc etc. For multiple values, you'd use define-values:

(define (t) (values 1 2))
(define-values (a b) (t))

or let-values. But note that I can't define t as a "tuple" since multiple values are not first class values in (most) scheme implementations.