Tuples

A tuple is a finite collection of values, possibly of different types. Tuples are created using the syntax (A, B, ...) where A, B and ... represent the values stored in a tuple. For example:

(10, 20, 30)

This expression returns a tuple with three values: 10, 20 and 30. Unlike arrays, the values don't need to be of the same type:

(10, 'hello', true)

Tuples are finite meaning that they have a fixed length, unlike arrays which can grow in size. This means there's no equivalent of Array.push, Array.pop and so on.

Accessing tuple values

Tuple values are accessed using their position, using the syntax the_tuple.N where N is the index starting at 0:

let pair = (10, 'hello')

pair.0 # => 10
pair.1 # => 'hello'

Tuples are inline types

Tuples are inline types and thus are stored on the stack. This means it's not possible to assign a new value to a tuple:

let pair = (10, 'hello')

pair.0 = 20 # => not valid, resulting in a compile-time error

Limitations

The tuple syntax is syntax sugar for creating instances of the various tuple types provided by the std.tuple module. For example, the expression (10, 'hello') is syntax sugar for creating an instance of std.tuple.Tuple2. The std.tuple module only provides types for tuples with up to 8 values, and thus tuples can only store at most 8 values.