Function rocket::mtls::oid::asn1_rs::nom::combinator::verify

source ·
pub fn verify<I, O1, O2, E, F, G>(first: F, second: G) -> impl FnMut(I)
where I: Clone, E: ParseError<I>, F: Parser<I, O1, E>, G: Fn(&O2) -> bool, O1: Borrow<O2>, O2: ?Sized,
Available on crate feature mtls only.
Expand description

Returns the result of the child parser if it satisfies a verification function.

The verification function takes as argument a reference to the output of the parser.

use nom::combinator::verify;
use nom::character::complete::alpha1;

let mut parser = verify(alpha1, |s: &str| s.len() == 4);

assert_eq!(parser("abcd"), Ok(("", "abcd")));
assert_eq!(parser("abcde"), Err(Err::Error(("abcde", ErrorKind::Verify))));
assert_eq!(parser("123abcd;"),Err(Err::Error(("123abcd;", ErrorKind::Alpha))));