rocket::mtls::x509::der_parser::asn1_rs::nom::bits

Function bits

Source
pub fn bits<I, O, E1, E2, P>(parser: P) -> impl FnMut(I)
where E1: ParseError<(I, usize)> + ErrorConvert<E2>, E2: ParseError<I>, I: Slice<RangeFrom<usize>>, P: Parser<(I, usize), O, E1>,
Available on crate feature mtls only.
Expand description

Converts a byte-level input to a bit-level input, for consumption by a parser that uses bits.

Afterwards, the input is converted back to a byte-level parser, with any remaining bits thrown away.

ยงExample

use nom::bits::{bits, streaming::take};
use nom::error::Error;
use nom::sequence::tuple;
use nom::IResult;

fn parse(input: &[u8]) -> IResult<&[u8], (u8, u8)> {
    bits::<_, _, Error<(&[u8], usize)>, _, _>(tuple((take(4usize), take(8usize))))(input)
}

let input = &[0x12, 0x34, 0xff, 0xff];

let output = parse(input).expect("We take 1.5 bytes and the input is longer than 2 bytes");

// The first byte is consumed, the second byte is partially consumed and dropped.
let remaining = output.0;
assert_eq!(remaining, [0xff, 0xff]);

let parsed = output.1;
assert_eq!(parsed.0, 0x01);
assert_eq!(parsed.1, 0x23);