nom::number::streaming

Function i24

Source
pub fn i24<I, E: ParseError<I>>(
    endian: Endianness,
) -> fn(_: I) -> IResult<I, i32, E>
where I: Slice<RangeFrom<usize>> + InputIter<Item = u8> + InputLength,
Expand description

Recognizes a signed 3 byte integer

If the parameter is nom::number::Endianness::Big, parse a big endian i24 integer, otherwise if nom::number::Endianness::Little parse a little endian i24 integer. Streaming version: Will return Err(nom::Err::Incomplete(_)) if there is not enough data.

use nom::number::streaming::i24;

let be_i24 = |s| {
  i24::<_, (_, ErrorKind)>(nom::number::Endianness::Big)(s)
};

assert_eq!(be_i24(&b"\x00\x03\x05abcefg"[..]), Ok((&b"abcefg"[..], 0x000305)));
assert_eq!(be_i24(&b"\x01"[..]), Err(Err::Incomplete(Needed::new(2))));

let le_i24 = |s| {
  i24::<_, (_, ErrorKind)>(nom::number::Endianness::Little)(s)
};

assert_eq!(le_i24(&b"\x00\x03\x05abcefg"[..]), Ok((&b"abcefg"[..], 0x050300)));
assert_eq!(le_i24(&b"\x01"[..]), Err(Err::Incomplete(Needed::new(2))));