add readme

1 files changed, 9 insertions, 10 deletions

diff --git a/src/lib.rs b/src/lib.rs
index 6e3109d..61aeb72 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -5,17 +5,17 @@
 //! ```
 //! use growthring::{WALStoreAIO, wal::WALLoader};
 //! use futures::executor::block_on;
-//! // start from empty WAL (trucate = true)
+//! // Start with empty WAL (truncate = true).
 //! let store = WALStoreAIO::new("./walfiles", true, |_, _| {Ok(())});
 //! let mut wal = WALLoader::new(9, 8, 1000).recover(store).unwrap();
-//! // write a vector of records to WAL
+//! // Write a vector of records to WAL.
 //! for f in wal.grow(vec!["record1(foo)", "record2(bar)", "record3(foobar)"]).into_iter() {
 //!     let ring_id = block_on(f).unwrap().1;
 //!     println!("WAL recorded record to {:?}", ring_id);
 //! }
 //!
 //!
-//! // load from WAL if exists (trucate = false)
+//! // Load from WAL (truncate = false).
 //! let store = WALStoreAIO::new("./walfiles", false, |payload, ringid| {
 //!     // redo the operations in your application
 //!     println!("recover(payload={}, ringid={:?})",
@@ -24,22 +24,21 @@
 //!     Ok(())
 //! });
 //! let mut wal = WALLoader::new(9, 8, 1000).recover(store).unwrap();
-//! // We'll see the playback of the log even if there is no failure. Let's remove the old log
-//! // entries by assuming they are already persistent in your application.
+//! // We saw some log playback, even there is no failure.
+//! // Let's try to grow the WAL to create many files.
 //! let ring_ids = wal.grow((0..100).into_iter().map(|i| "a".repeat(i)).collect::<Vec<_>>())
 //!                   .into_iter().map(|f| block_on(f).unwrap().1).collect::<Vec<_>>();
-//!
-//!
-//! // Let's assume all these records are not longer needed. There will only be one remaining file
-//! // in ./walfiles
+//! // Then assume all these records are not longer needed. We can tell WALWriter by the `peel`
+//! // method.
 //! block_on(wal.peel(ring_ids)).unwrap();
+//! // There will only be one remaining file in ./walfiles.
 //!
 //! let store = WALStoreAIO::new("./walfiles", false, |payload, _| {
 //!     println!("payload.len() = {}", payload.len());
 //!     Ok(())
 //! });
 //! let wal = WALLoader::new(9, 8, 1000).recover(store).unwrap();
-//! // The ./walfiles is empty now as all records are played back.
+//! // After each recovery, the ./walfiles is empty.
 //! ```
 
 #[macro_use] extern crate scan_fmt;