2.7. Tuples

How many times have you wanted to return two or more values from a method? In many languages, like Java, you only have a few options, none of which is very appealing. You could pass in parameters to the method that will be modified for all or some of the “return” values, which is ugly. Or you could declare some small “structural” class that holds the two or more values, then return an instance of that class.

Scala, supports tuples, a grouping of two or more items, usually created with the literal syntax of a comma-separated list of the items inside parentheses, e.g., (x1, x2, ...). The types of the x_i elements are unrelated to each other; you can mix and match types. These literal “groupings” are instantiated as scala.TupleN instances, where N is the number of items in the tuple. The Scala API defines separate TupleN classes for N between 1 and 22, inclusive. Tuple instances are immutable, first-class values, so you can assign them to variables, pass them as values, and return them from methods.