Can't reference Sink in struct

[ferristseng]

The Sink type is private, but parse_html returns a Parser<Sink> type.

This makes it impossible to reference the return type in a struct:

struct App {
    config: Config,
    current_parser: Option<Parser<Sink>>, // <-- Can't do this
    buffer: [u8; 1024],
    counter: usize,
}