Macro nom::separated_pair

macro_rules! separated_pair {
    ($i:expr, $submac:ident!( $($args:tt)* ), $($rest:tt)*) => { ... };
    ($i:expr, $f:expr, $submac:ident!( $($args:tt)* ), $($rest:tt)*) => { ... };
    ($i:expr, $f:expr, $g:expr, $submac:ident!( $($args:tt)* )) => { ... };
    ($i:expr, $f:expr, $g:expr, $h:expr) => { ... };
}

separated_pair!(I -> IResult<I,O>, I -> IResult<I, T>, I -> IResult<I,P>) => I -> IResult<I, (O,P)> separated_pair(X,sep,Y) returns a tuple of its first and third child parsers if all 3 succeed.

named!(parser<&str, (&str, &str)>, separated_pair!(alpha1, char!(','), digit1));

assert_eq!(parser("abc,123"), Ok(("", ("abc", "123"))));
assert_eq!(parser("123,abc"), Err(Err::Error(Error::new("123,abc", ErrorKind::Alpha))));
assert_eq!(parser("abc;123"), Err(Err::Error(Error::new(";123", ErrorKind::Char))));