You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: mod.rs
    path of file: ./repos/surrealdb/core/src/kvs/mem
    
    the code of the file until where you have to start completion: #![cfg(feature = "kv-mem")]

use crate::err::Error;
use crate::kvs::Check;
use crate::kvs::Key;
use crate::kvs::Val;
use crate::vs::{try_to_u64_be, u64_to_versionstamp, Versionstamp};
use std::ops::Range;

pub struct D
    
	pub(crate) fn commit(&mut self) -> Result<(), Error> {
		// Check to see if transaction is closed
		if self.done {
			return Err(Error::TxFinished);
		}
		// Check to see if transaction is writable
		if !self.write {
			return Err(Error::TxReadonly);
		}
		// Mark this transaction as done
		self.done = true;
		// Cancel this transaction
		self.inner.commit()?;
		// Continue
		Ok(())
	}