Move concrete Cursor definitions on top

storage_engine/src/cursor.rs

@@ -15,6 +15,25 @@ use crate::entry_header::{EntryHeaderWithDataSize, EntryHeader};
 use crate::store_header::StoreHeader;
 use crate::storage_engine::{Store, FilePosition, Column, Result, ROWS_FILE_NAME, GARBAGE_COLLECTION_INTERMEDIATE_ROWS_FILE_NAME};
 
+// ===Concrete Cursors===
+pub struct ReadCursor<T> {
+    header: StoreHeader,
+    file: File,
+    data_type: PhantomData<T>,
+
+    eof_file_position: FilePosition,
+}
+
+pub struct WriteCursor<'a, T> {
+    header: &'a mut StoreHeader,
+    file: File,
+    data_type: PhantomData<T>,
+
+    eof_file_position: FilePosition,
+}
+
+
+// ===Traits===
 #[async_trait]
 // TODO: Make this private
 pub trait PrimitiveCursor<T> {
@@ -206,23 +225,6 @@ pub trait CursorWithStoreHeader<T>: PrimitiveCursor<T> {
 }
 
 
-// ===Concrete Cursors===
-pub struct ReadCursor<T> {
-    header: StoreHeader,
-    file: File,
-    data_type: PhantomData<T>,
-
-    eof_file_position: FilePosition,
-}
-
-pub struct WriteCursor<'a, T> {
-    header: &'a mut StoreHeader,
-    file: File,
-    data_type: PhantomData<T>,
-
-    eof_file_position: FilePosition,
-}
-
 // ===PrimitiveCursor===
 impl <T>PrimitiveCursor<T> for ReadCursor<T> {
     fn file(&mut self) -> &mut File {