Function winnow::combinator::preceded

source · 
pub fn preceded<Input, Ignored, Output, Error, IgnoredParser, ParseNext>(
    ignored: IgnoredParser,
    parser: ParseNext
) -> impl Parser<Input, Output, Error>
where
    Input: Stream,
    Error: ParserError<Input>,
    IgnoredParser: Parser<Input, Ignored, Error>,
    ParseNext: Parser<Input, Output, Error>,
Expand description

Sequence two parsers, only returning the output from the second.

See also seq to generalize this across any number of fields.

§Example

use winnow::combinator::preceded;

let mut parser = preceded("abc", "efg");

assert_eq!(parser.parse_peek("abcefg"), Ok(("", "efg")));
assert_eq!(parser.parse_peek("abcefghij"), Ok(("hij", "efg")));
assert_eq!(parser.parse_peek(""), Err(ErrMode::Backtrack(InputError::new("", ErrorKind::Tag))));
assert_eq!(parser.parse_peek("123"), Err(ErrMode::Backtrack(InputError::new("123", ErrorKind::Tag))));