Why is Scala's syntax for tuples so unusual?

Question

In mathematics and computer science, a tuple is an ordered list of elements. In set theory, an (ordered) n-tuple is a sequence (or ordered list) of n elem

Answer 1

One big difference between List, Seq or any collection and tuple is that in tuple each element has it's own type where in List all elements have the same type.

And as consequence, in Scala you will find classes like Tuple2[T1, T2] or Tuple3[T1, T2, T3], so for each element you also have type parameter. Collections accept only 1 type parameter: List[T]. Syntax like ("Test", 123, new Date) is just syntactic sugar for Tuple3[String, Int, Date]. And _1, _2, etc. are just fields on tuple that return correspondent element.