nom::is_not!

macro_rules! is_not(
  ($input:expr, $arr:expr) => (
    {
      #[inline(always)]
      fn as_bytes<T: $crate::AsBytes>(b: &T) -> &[u8] {
        b.as_bytes()
      }

      let expected   = $arr;
      let bytes      = as_bytes(&expected);
      let mut parsed = false;
      let mut index  = 0;

      for idx in 0..$input.len() {
        index = idx;
        for &i in bytes.iter() {
          if $input[idx] == i {
            parsed = true;
            break;
          }
        }
        if parsed { break; }
      }
      if index == 0 {
        $crate::IResult::Error($crate::Err::Position($crate::ErrorCode::IsNot as u32,$input))
      } else {
        $crate::IResult::Done(&$input[index..], &$input[0..index])
      }
    }
  );
);

is_not!(&[T:AsBytes]) => &[T] -> IResult<&[T], &[T]> returns the longest list of bytes that do not appear in the provided array

 named!( not_space, is_not!( " \t\r\n" ) );

 let r = not_space(&b"abcdefgh\nijkl"[..]);
 assert_eq!(r, Done(&b"\nijkl"[..], &b"abcdefgh"[..]));