Function no_partial 

pub fn no_partial<Input, P>(p: P) -> NoPartial<P>
where
    Input: Stream,
    P: Parser<Input>,

Wraps a parser p and disables partial parsing for it (changing the PartialState to ())

Partial parsing lets a parser accept incomplete (partial) input resume parsing when more input is available without re-parsing any part of the input. By disabling partial parsing for a parser it will need to restart its parse from the beginning once more input is available (no_partial ONLY affects the wrapped parser, any parsers calling the no_partial parser will still employ partial parsing).

If you are not using partial parsing this has no effect (except changing the typing of the parser).

assert_eq!(
    (no_partial(letter()), letter()).easy_parse("ab"),
    Ok((('a', 'b'), ""))
);