   @doc """
   Checks if `string` contains any of the given `contents`.
 
-  `matches` can be either a single string or a list of strings.
+  `contents` can be either a single string or a list of strings.
 
   ## Examples
 

  end

  @doc """
  Returns the last grapheme from an utf8 string,
  `nil` if the string is empty.

  ## Examples

  defdelegate upcase(binary), to: String.Unicode

  @doc """
  Converts all characters in the given string to lowercase.

  ## Examples

