Remove unnecessar PhantomData

storage_engine/src/cursor.rs

@@ -2,7 +2,7 @@ use tokio::io::{AsyncReadExt, AsyncWriteExt, AsyncSeekExt, SeekFrom};
 use tokio::fs::{File, OpenOptions};
 use std::path::Path;
 use std::marker::PhantomData;
-use crate::error::{Error, DecodeErrorKind};
+use std::collections::{BTreeMap, HashSet};
 
 use async_trait::async_trait;
 
@@ -10,6 +10,7 @@ use bincode;
 use bincode::{Decode, Encode};
 use crate::binary_coding::{encode, decode};
 
+use crate::error::{Error, DecodeErrorKind};
 use crate::entry::{Entry, EntryDetailed};
 use crate::entry_header::{EntryHeaderWithDataSize, EntryHeader};
 use crate::store_header::StoreHeader;
@@ -23,7 +24,6 @@ pub struct ReadCursor<'a, T> {
     header: StoreHeader,
     indexes: &'a [Option<Index<T, FilePosition>>],
     file: File,
-    data_type: PhantomData<T>,
 
     eof_file_position: FilePosition,
 }
@@ -32,7 +32,6 @@ pub struct WriteCursor<'a, T> {
     header: &'a mut StoreHeader,
     indexes: &'a mut [Option<Index<T, FilePosition>>],
     file: File,
-    data_type: PhantomData<T>,
 
     eof_file_position: FilePosition,
 }
@@ -390,7 +389,6 @@ impl <'cursor, T> ReadCursor<'cursor, T> {
             let mut cursor = Self {
                 header: store.header.clone(),
                 file,
-                data_type: store.data_type,
                 indexes: &store.indexes,
 
                 eof_file_position: 0,
@@ -425,7 +423,6 @@ impl <'cursor, T> WriteCursor<'cursor, T>
             let mut cursor = Self {
                 header: &mut store.header,
                 file,
-                data_type: store.data_type,
                 indexes: &mut store.indexes,
 
                 eof_file_position: 0,
@@ -451,7 +448,6 @@ impl <'cursor, T> WriteCursor<'cursor, T>
             let mut cursor = Self {
                 header,
                 file,
-                data_type: PhantomData::<T>,
                 indexes,
 
                 eof_file_position: 0,
@@ -476,7 +472,7 @@ impl <'cursor, T> WriteCursor<'cursor, T>
 
     // ===Deletion===
     pub async fn mark_deleted_at(&mut self, file_position: FilePosition) -> Result<()> 
-        where T: Send
+        where T: Send + Decode + Encode
     {
         self.seek_to(file_position).await?;
         let mut entry_header = self.read_entry_header().await?;
@@ -495,7 +491,7 @@ impl <'cursor, T> WriteCursor<'cursor, T>
     }
 
     async fn find_first_eq_bruteforce_and_delete(&mut self, column: Column, t0: &T) -> Result<Option<EntryDetailed<T>>> 
-        where T: Decode + PartialEq + Send + Sync
+        where T: Decode + Encode + PartialEq + Send + Sync
     {
         let maybe_entry = self.find_first_eq_bruteforce(column, t0).await?;
         if let Some(entry) = maybe_entry {
@@ -508,7 +504,7 @@ impl <'cursor, T> WriteCursor<'cursor, T>
 
     // ===Garbage Collection===
     async fn attempt_garbage_collection_if_necessary(&mut self) -> Result<()> 
-        where T: Send
+        where T: Send + Decode + Encode
     {
         // TODO: What should be the policy? Counting size of garbage? Counting how many entries are
         // garbage?
@@ -519,11 +515,18 @@ impl <'cursor, T> WriteCursor<'cursor, T>
     }
 
     async fn initiate_garbage_collection(&mut self) -> Result<usize> 
-        where T: Send
+        where T: Send + Decode + Encode
     {
-        // We'll dump all alive entries into a new file.
         let mut cursor_to_intermediate = self.spawn_cursor_to_intermediate_file().await?;
 
+        let in_memory_index: BTreeMap<T, HashSet<FilePosition>> = BTreeMap::new();
+
+        // We'll dump all alive entries into a new file.
+        while let Some(live_entry) = self.next_alive().await? {
+            let file_position = cursor_to_intermediate.append_entry(&live_entry.forget()).await?;
+            // TODO: Start indexing all of the indexable columns from scratch.
+        }
+
         // In it there will be only the alive rows.
         // Afterwards we swap the files, and delete the garbage.
         todo!()

storage_engine/src/entry.rs

@@ -48,4 +48,11 @@ impl <T>EntryDetailed<T> {
             .map_err(|e| Error::DecodeError(DecodeErrorKind::EntryData, e))?;
         Ok(EntryDetailed { header, file_position, data })
     }
+
+    pub fn forget(self) -> Entry<T> {
+        Entry {
+            header: self.header.into(),
+            data: self.data,
+        }
+    }
 }

storage_engine/src/storage_engine.rs

@@ -20,7 +20,6 @@ pub type FilePosition = u64;
 #[derive(Debug)]
 pub struct Store<T> {
     pub header: StoreHeader,
-    pub data_type: PhantomData<T>,
     pub indexes: StoreIndexes<T>,
 }
 
@@ -68,7 +67,6 @@ impl <T>Store<T> {
 
         let store = Self {
             header,
-            data_type: PhantomData::<T>,
             indexes,
         };
 
@@ -171,7 +169,6 @@ impl <T>Store<T> {
 
         let store = Self {
             header,
-            data_type: PhantomData::<T>,
             indexes
         };
         Ok(store)