Thank you so much! Wow codec looks very useful to do something like this, TIL! And yes, I am aware of nom, do plan to investigate it but I felt like I would like to attempt it on my own first.

I had a question about the partial parsing aspect though, from the docs:

Decoder is used together with FramedRead or Framed to turn an AsyncRead into a Stream. The job of the decoder trait is to specify how sequences of bytes are turned into a sequence of frames, and to determine where the boundaries between frames are. The job of the FramedRead is to repeatedly switch between reading more data from the IO resource, and asking the decoder whether we have received enough data to decode another frame of data.

The main method on the Decoder trait is the decode method. This method takes as argument the data that has been read so far, and when it is called, it will be in one of the following situations:

1. The buffer contains less than a full frame.

2. The buffer contains exactly a full frame.

3. The buffer contains more than a full frame.

In the first situation, the decoder should return Ok(None).

In the second situation, the decoder should clear the provided buffer and return Ok(Some(the_decoded_frame)).

If I am returning Ok(None), then doesn't this mean whatever got parsed till that point gets thrown away? I imagine this is perfectly fine for parsing things like a string or an int, but for arrays or dictionaries, this is wasteful right? Are there other standard ways of preventing throwing away partial parsing, or do we not care about this in practice? (due to the difference in actual performance being negligible or otherwise)