[Question] Melting

[gooftroop]

Do you have an example of how to save the gamestate to a new file? I'm new to rust so reading the melter is only getting me so far

[nickbabcock]

What are you trying to accomplish? Sounds like you are after save file editing, if so, you may be interested in pdxu.

[gooftroop]

I am, but the existing tools don't do exactly want I want, so I'm using your library to build one out. I've got a modified gamestate that I want to write back to a file - is this something that your library can do now or something I can easily add?

[nickbabcock]

If I understand correctly, you want to splice in data in an already existing save. That is a tough problem as the deserialized model is often only a partial view of the data.

There is a write API available (it's not exposed on save files, as I didn't intend for this use case, but it's a change that can be made). You can drive a creation of a save through that API when all the data is known.

Here's an example of splicing in "is_human=yes" and adjusting the positions of everything after insertion.

    let data = b"foo=bar a={b=1} d={c}";
    let tape = TextTape::from_slice(&data[..]).unwrap();
    let mut edit = tape.tokens().to_vec();
    let start = edit
        .iter()
        .position(|x| matches!(x, TextToken::Unquoted(i) if i.as_bytes() == b"a"))
        .unwrap();

    edit.insert(start + 2, TextToken::Unquoted(Scalar::new(b"yes")));
    edit.insert(start + 2, TextToken::Unquoted(Scalar::new(b"is_human")));
    for token in &mut edit[start..] {
        match token {
            TextToken::End(x) if *x > start => *x += 2,
            TextToken::Array { end, .. } | TextToken::Object { end, .. } => *end += 2,
            _ => {}
        }
    }

    let out_tape = TextTape::from_tokens(edit);
    let mut out: Vec<u8> = Vec::new();
    let mut writer = TextWriterBuilder::new().indent_char(b' ').indent_factor(2).from_writer(&mut out);
    writer.write_tape(&out_tape).unwrap();
    assert_eq!(&out, br#"foo=bar
a={
  is_human=yes
  b=1
}
d={
  c
}"#);

[gooftroop]

hmm this would mean that I'd need to serialize the structs, probably by implementing a custom Serialize for serde? I can try and fork Jomini and give it a try (no guarantees on the best code...my forte is in c# and js)