Functions for working with tuples.

Please note the following functions for tuples are found in Kernel:

• elem/2 - accesses a tuple by index
• put_elem/3 - inserts a value into a tuple by index
• tuple_size/1 - gets the number of elements in a tuple

Tuples are intended as fixed-size containers for multiple elements. To manipulate a collection of elements, use a list instead. Enum functions do not work on tuples.

Tuples are denoted with curly braces:

iex> {}
{}
iex> {1, :two, "three"}
{1, :two, "three"}

A tuple may contain elements of different types, which are stored contiguously in memory. Accessing any element takes constant time, but modifying a tuple, which produces a shallow copy, takes linear time. Tuples are good for reading data while lists are better for traversals.

Tuples are typically used either when a function has multiple return values or for error handling. File.read/1 returns {:ok, contents} if reading the given file is successful, or else {:error, reason} such as when the file does not exist.

The functions in this module that add and remove elements from tuples are rarely used in practice, as they typically imply tuples are being used as collections. To append to a tuple, it is preferable to extract the elements from the old tuple with pattern matching, and then create a new tuple:

tuple = {:ok, :example}

# Avoid
result = Tuple.insert_at(tuple, 2, %{})

# Prefer
{:ok, atom} = tuple
result = {:ok, atom, %{}}