How does compression work?

[johannesCmayer]

Hi,

Could somebody explain to me how the compression works? I am slow to understand the code. I'd guess that summarize is called repeatedly for the start of the session text, to replace the current text, until we are under the compression threshold.

Is this a destructive edit, or is the previous session text saved somewhere?

I think it would be good if this was explained at least briefly in the main readme.

[sigoden]

aichat/src/config/mod.rs

Lines 795 to 810 in 5635ca6

	pub fn should_compress_session(&mut self) -> bool {
	if let Some(session) = self.session.as_mut() {
	if session.need_compress(self.compress_threshold) {
	session.compressing = true;
	return true;
	}
	}
	false
	}
	pub fn compress_session(&mut self, summary: &str) {
	if let Some(session) = self.session.as_mut() {
	let summary_prompt = self.summary_prompt.as_deref().unwrap_or(SUMMARY_PROMPT);
	session.compress(format!("{}{}", summary_prompt, summary));
	}
	}

aichat/src/config/session.rs

Lines 297 to 302 in 5635ca6

	pub fn compress(&mut self, prompt: String) {
	self.compressed_messages.append(&mut self.messages);
	self.messages.push(Message::new(
	MessageRole::System,
	MessageContent::Text(prompt),
	));