Function combine::byte::lower

pub fn lower<I>() -> Lower<I> where
    I: Stream<Item = u8>, 

Parses an lowercase ASCII letter (a–z).

use combine::Parser;
use combine::byte::lower;
assert_eq!(lower().parse(&b"a"[..]), Ok((b'a', &b""[..])));
assert!(lower().parse(&b"A"[..]).is_err());