Is there a way to make .padded().repeated() stop when encountering pattern?

[SergeyKasmy]

Hello.

I'm looking for a way to make a .padded().repeated() parser stop at an empty new line, i.e. newline().then(newline()) but sadly I haven't been successful.

For example, I have a file formatted like this:

HEADER1:
    stuff
    more_stuff

HEADER2: foo bar

At first, to parse HEADER1, I came up with something like this

let empty_line = newline().then(newline());

let header1= just(b"HEADER1:")
  .ignore_then(
    text::ident::<u8, Simple<u8>>()
      .padded()
      .repeated()
  );

Sadly this obviously eats up every other input after HEADER1.

Adding .then_ignore(empty_line) at the end doesn't work because .repeated() is eagerly evaluated.

I've tried replacing .padded() with .padded_by(empty_line.not().or(whitespace())) but it screams at me that empty_line and whitespace() parsers return different values.

Just making header1 the last parser in the chain isn't an option because I want to report any unrecognized lines in the file and not interpret them as part of header1, e.g. I want this to error:

HEADER2: foo bar

HEADER1:
    stuff

UNKNOWN_HEADER: bad

Is there anything I can do to make the .padded().repeated() parser stop at \n\n?

Thanks!

[zesterer]

You can do something like a.and_is(b.not()).repeated() to make the repeating pattern stop when it finds a b. This works even if a would normally successfully parse b.