Function winnow::combinator::separated_foldr1

pub fn separated_foldr1<Input, Output, Sep, Error, ParseNext, SepParser, Op>(
    parser: ParseNext,
    sep: SepParser,
    op: Op,
) -> impl Parser<Input, Output, Error>
where
    Input: Stream,
    ParseNext: Parser<Input, Output, Error>,
    SepParser: Parser<Input, Sep, Error>,
    Error: ParserError<Input>,
    Op: FnMut(Output, Sep, Output) -> Output,

Available on crate feature alloc only.

Alternates between two parsers, merging the results (right associative)

This stops when either parser returns ErrMode::Backtrack. To instead chain an error up, see cut_err.

Example

use winnow::combinator::separated_foldr1;
use winnow::ascii::dec_uint;

fn parser(s: &str) -> IResult<&str, u32> {
  separated_foldr1(dec_uint, "^", |l: u32, _, r: u32| l.pow(r)).parse_peek(s)
}

assert_eq!(parser("2^3^2"), Ok(("", 512)));
assert_eq!(parser("2"), Ok(("", 2)));
assert_eq!(parser(""), Err(ErrMode::Backtrack(InputError::new("", ErrorKind::Token))));
assert_eq!(parser("def|abc"), Err(ErrMode::Backtrack(InputError::new("def|abc", ErrorKind::Verify))));