Atom

Atoms are constants whose values are their own name.

They are often useful to enumerate over distinct values, such as:

:apple

:orange

:watermelon

Atoms are equal if their names are equal.

:apple == :apple

:apple == :orange

Often they are used to express the state of an operation, by using values such as :ok and :error.

The booleans true and false are also atoms:

true == true

is_atom(false)

is_boolean(false)

Elixir allows you to skip the leading : for the atoms false, true, and nil.

Atoms must be composed of Unicode characters such as letters, numbers, underscore, and @. If the keyword has a character that does not belong to the category above, such as spaces, you can wrap it in quotes:

:"this is an atom with spaces"

Function to_charlist/1

Converts an atom to a charlist.

Inlined by the compiler.

Examples

Atom.to_charlist(:"An atom")

Function to_string/1

Converts an atom to a string.

Inlined by the compiler.

Examples

Atom.to_string(:foo)