Function nom::multi::many_m_n

pub fn many_m_n<I, O, E, F>(
    min: usize,
    max: usize,
    parse: F
) -> impl FnMut(I) -> IResult<I, Vec<O>, E>
where
    I: Clone + InputLength,
    F: Parser<I, O, E>,
    E: ParseError<I>,

Repeats the embedded parser m..=n times

This stops before n when the parser returns Err::Error and returns the results that were accumulated. To instead chain an error up, see cut.

Arguments

• m The minimum number of iterations.
• n The maximum number of iterations.
• f The parser to apply.

Note: If the parser passed to many1 accepts empty inputs (like alpha0 or digit0), many1 will return an error, to prevent going into an infinite loop.

use nom::multi::many_m_n;
use nom::bytes::complete::tag;

fn parser(s: &str) -> IResult<&str, Vec<&str>> {
  many_m_n(0, 2, tag("abc"))(s)
}

assert_eq!(parser("abcabc"), Ok(("", vec!["abc", "abc"])));
assert_eq!(parser("abc123"), Ok(("123", vec!["abc"])));
assert_eq!(parser("123123"), Ok(("123123", vec![])));
assert_eq!(parser(""), Ok(("", vec![])));
assert_eq!(parser("abcabcabc"), Ok(("abc", vec!["abc", "abc"])));