pub fn preceded<I, O1, O2, E: ParseError<I>, F, G>(
first: F,
second: G
) -> impl FnMut(I) -> IResult<I, O2, E> where
F: Parser<I, O1, E>,
G: Parser<I, O2, E>,
Expand description
Matches an object from the first parser and discards it, then gets an object from the second parser.
Arguments
first
The opening parser.second
The second parser to get object.
use nom::sequence::preceded;
use nom::bytes::complete::tag;
let mut parser = preceded(tag("abc"), tag("efg"));
assert_eq!(parser("abcefg"), Ok(("", "efg")));
assert_eq!(parser("abcefghij"), Ok(("hij", "efg")));
assert_eq!(parser(""), Err(Err::Error(("", ErrorKind::Tag))));
assert_eq!(parser("123"), Err(Err::Error(("123", ErrorKind::Tag))));