Atom — Elixir v1.16.3

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# View Source Atom (Elixir v1.16.3)

Atoms are constants whose values are their own name.

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

    iex> :apple
    :apple
    iex> :orange
    :orange
    iex> :watermelon
    :watermelon

Atoms are equal if their names are equal.

    iex> :apple == :apple
    true
    iex> :apple == :orange
    false

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:

    iex> true == :true
    true
    iex> is_atom(false)
    true
    iex> is_boolean(:false)
    true

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:

    iex> :"this is an atom with spaces"
    :"this is an atom with spaces"

# Summary

## Functions

to_charlist(atom)

Converts an atom to a charlist.

to_string(atom)

Converts an atom to a string.

# Functions

Link to this function

# to_charlist(atom)

View Source

    @spec to_charlist(atom()) :: charlist()

Converts an atom to a charlist.

Inlined by the compiler.

## Examples

    iex> Atom.to_charlist(:"An atom")
    'An atom'

Link to this function

# to_string(atom)

View Source

    @spec to_string(atom()) :: String.t()

Converts an atom to a string.

Inlined by the compiler.

## Examples

    iex> Atom.to_string(:foo)
    "foo"