This is normal. See https://elixir-lang.org/getting-started/binaries-strings-and-char-lists.html#charlists for an explanation. Tl;Dr is that in erlang strings are lists of numbers, and elixir has a syntax for that as well to promote compatibility with Erlang.
Edit: also want to point out, you do have a list of numbers there, it’s just printed differently. Eg
'\f' == [12]
