Error with bitwise NOT operator inside binary

[eksperimental]

bitstring(Var) ->
  <<(bnot Var)/integer>>.

is transpiled as:

  defp bitstring(var) do
    <<~~~ var :: integer>>
  end

and you will get a compile error.
unexpected token: "~" (column 8, code point U+007E)

it should use parenthesis (and preferable leave lo space between the operator and the term with the bitwise operators in general.)
<<(~~~var) :: integer>>