# Function nom::combinator::not

source · [−]

    pub fn not<I: Clone, O, E: ParseError<I>, F>(
        parser: F
    ) -> impl FnMut(I) -> IResult<I, (), E> where
        F: Parser<I, O, E>,

Expand description

Succeeds if the child parser returns an error.

    use nom::combinator::not;
    use nom::character::complete::alpha1;

    let mut parser = not(alpha1);

    assert_eq!(parser("123"), Ok(("123", ())));
    assert_eq!(parser("abcd"), Err(Err::Error(("abcd", ErrorKind::Not))));