Function winnow::number::u16

source ·
pub fn u16<I, E: ParseError<I>>(
    endian: Endianness
) -> impl FnMut(I) -> IResult<I, u16, E>where
    I: StreamIsPartial + Stream<Token = u8>,
    <I as Stream>::Slice: AsBytes,
Expand description

Recognizes an unsigned 2 bytes integer

If the parameter is winnow::number::Endianness::Big, parse a big endian u16 integer, otherwise if winnow::number::Endianness::Little parse a little endian u16 integer.

Complete version: returns an error if there is not enough input data

Partial version: Will return Err(winnow::error::ErrMode::Incomplete(_)) if there is not enough data.

Example

use winnow::number::u16;

let be_u16 = |s| {
  u16(winnow::number::Endianness::Big)(s)
};

assert_eq!(be_u16(&b"\x00\x03abcefg"[..]), Ok((&b"abcefg"[..], 0x0003)));
assert_eq!(be_u16(&b"\x01"[..]), Err(ErrMode::Backtrack(Error::new(&[0x01][..], ErrorKind::Eof))));

let le_u16 = |s| {
  u16(winnow::number::Endianness::Little)(s)
};

assert_eq!(le_u16(&b"\x00\x03abcefg"[..]), Ok((&b"abcefg"[..], 0x0300)));
assert_eq!(le_u16(&b"\x01"[..]), Err(ErrMode::Backtrack(Error::new(&[0x01][..], ErrorKind::Eof))));
use winnow::number::u16;

let be_u16 = |s| {
  u16::<_, Error<_>>(winnow::number::Endianness::Big)(s)
};

assert_eq!(be_u16(Partial::new(&b"\x00\x03abcefg"[..])), Ok((Partial::new(&b"abcefg"[..]), 0x0003)));
assert_eq!(be_u16(Partial::new(&b"\x01"[..])), Err(ErrMode::Incomplete(Needed::new(1))));

let le_u16 = |s| {
  u16::<_, Error<_>>(winnow::number::Endianness::Little)(s)
};

assert_eq!(le_u16(Partial::new(&b"\x00\x03abcefg"[..])), Ok((Partial::new(&b"abcefg"[..]), 0x0300)));
assert_eq!(le_u16(Partial::new(&b"\x01"[..])), Err(ErrMode::Incomplete(Needed::new(1))));