Trait winnow::stream::ContainsToken

source · 
pub trait ContainsToken<T> {
    fn contains_token(&self, token: T) -> bool;
}
Expand description

Check if a token in in a set of possible tokens

This is generally implemented on patterns that a token may match and supports u8 and char tokens along with the following patterns

  • b'c' and 'c'
  • b"" and ""
  • |c| true
  • b'a'..=b'z', 'a'..='z' (etc for each range type)
  • (pattern1, pattern2, ...)

Example

For example, you could implement hex_digit0 as:

fn hex_digit1(input: &str) -> IResult<&str, &str> {
    take_while1(('a'..='f', 'A'..='F', '0'..='9')).parse_next(input)
}

assert_eq!(hex_digit1("21cZ"), Ok(("Z", "21c")));
assert_eq!(hex_digit1("H2"), Err(ErrMode::Backtrack(Error::new("H2", ErrorKind::Slice))));
assert_eq!(hex_digit1(""), Err(ErrMode::Backtrack(Error::new("", ErrorKind::Slice))));

Required Methods§

Returns true if self contains the token

Implementations on Foreign Types§

Implementors§