comprehensions in dynamo

0-before.ex

defp escape(key) do
  bc <<code>> inbits key do
    << if code in [?[, ?], ?{, ?}, ?*, ??] do
         << ?\\, code >>
       else
         << code >>
       end :: binary >>
  end
end

1-after.ex

defp escape(key) do
  for <<code <- key>> do
    << if code in [?[, ?], ?{, ?}, ?*, ??] do
         << ?\\, code >>
       else
         << code >>
       end :: binary >>
  end
end