[steveklabnik]

Fully acknowledge your final paragraphs here, for sure. But in case you're curious...

I think that if you wrote

  for (term, buff) in self.buffers {

it should have Just Worked. By iterating over a reference to self.buffers, you iterate over a reference to the contents, which you can't move out of. But iterating over it by value, it should give it to you by value, and you'd be fine. That said, I have not tried it, so there might be some context I'm missing. One nice thing about a strict compiler is that I have to think about the details less, and use the error messages to help me fix any problems I find. But that makes it harder to know how it goes without the compiler...

[atombender]

No, I tried that! That actually moves the "Cannot move" error to the "self.buffers" use itself.

The reason I can't just iterate by value is that I'd be consuming data that is already held by the map. The buffer is defined thus:

  use bitstream_io::{BigEndian, BitWriter};

  struct PostingBuffer<W: io::Write> {
    bw: BitWriter<W, BigEndian>,
    // ...
  }

  impl PostingBuffer {
    pub fn get_data(self) -> W {
      self.bw.into_writer()
    }
  }

bitstream_io::BitWriter's [1] into_writer consumes itself:

  pub fn into_writer(self) -> W {
    self.writer
  }

[1] https://docs.rs/bitstream-io/0.8.2/bitstream_io/write/struct...

[steveklabnik]

Ah, ah, I see now. Yes, right.

This is exactly why I couched my last paragraph the way I did, heh.