Elaborate on which characters are considered printable in charlists (#8492)

1 files changed, 17 insertions, 3 deletions

diff --git a/lib/elixir/lib/list.ex b/lib/elixir/lib/list.ex
index 8addc819f..87346662d 100644
--- a/lib/elixir/lib/list.ex
+++ b/lib/elixir/lib/list.ex
@@ -448,14 +448,28 @@ defmodule List do
     do_zip(list_of_lists, [])
   end
 
-  @doc """
+  @doc ~S"""
   Checks if a list is a charlist made only of printable ASCII characters.
 
-  A printable charlist in Elixir contains only ASCII characters.
-
   Takes an optional `limit` as a second argument. `ascii_printable?/2` only
   checks the printability of the list up to the `limit`.
 
+  A printable charlist in Elixir contains only the printable characters in the
+  standard seven-bit ASCII character encoding, which are characters ranging from
+  32 to 126 in decimal notation, plus the following control characters:
+
+    * `?\a` - Bell
+    * `?\b` - Backspace
+    * `?\t` - Horizontal tab
+    * `?\n` - Line feed
+    * `?\v` - Vertical tab
+    * `?\f` - Form feed
+    * `?\r` - Carriage return
+    * `?\e` - Escape
+
+  For more information read the [Character groups](https://en.wikipedia.org/wiki/ASCII#Character_groups)
+  section in the Wikipedia article of the [ASCII](https://en.wikipedia.org/wiki/ASCII) standard.
+
   ## Examples
 
       iex> List.ascii_printable?('abc')