Use associated types instead of generics

src/vtab/csvtab.rs

@@ -89,7 +89,9 @@ impl CSVTab {
     }
 }
 
-impl VTab<CSVTabCursor> for CSVTab {
+impl VTab for CSVTab {
+    type Cursor = CSVTabCursor;
+
     unsafe fn connect(db: *mut ffi::sqlite3, _aux: *mut c_void, args: &[&[u8]]) -> Result<CSVTab> {
         if args.len() < 4 {
             return Err(Error::ModuleError("no CSV file specified".to_owned()));
@@ -246,7 +248,9 @@ impl CSVTabCursor {
     }
 }
 
-impl VTabCursor<CSVTab> for CSVTabCursor {
+impl VTabCursor for CSVTabCursor {
+    type Table = CSVTab;
+
     fn vtab(&self) -> &CSVTab {
         unsafe { & *(self.base.pVtab as *const CSVTab) }
     }

src/vtab/int_array.rs

@@ -59,7 +59,9 @@ struct IntArrayVTab {
     array: *const Rc<RefCell<Vec<i64>>>,
 }
 
-impl VTab<IntArrayVTabCursor> for IntArrayVTab {
+impl VTab for IntArrayVTab {
+    type Cursor = IntArrayVTabCursor;
+
     unsafe fn connect(db: *mut ffi::sqlite3,
                aux: *mut c_void,
                _args: &[&[u8]])
@@ -100,7 +102,9 @@ impl IntArrayVTabCursor {
     }
 }
 
-impl VTabCursor<IntArrayVTab> for IntArrayVTabCursor {
+impl VTabCursor for IntArrayVTabCursor {
+    type Table = IntArrayVTab;
+
     fn vtab(&self) -> &IntArrayVTab {
         unsafe { & *(self.base.pVtab as *const IntArrayVTab) }
     }

src/vtab/mod.rs

@@ -41,7 +41,8 @@ use types::{FromSql, FromSqlError, ToSql, ValueRef};
 //
 
 /// Virtual table instance trait.
-pub trait VTab<C: VTabCursor<Self>>: Sized {
+pub trait VTab: Sized {
+    type Cursor: VTabCursor;
     /// Create a new instance of a virtual table in response to a CREATE VIRTUAL TABLE statement.
     /// The `db` parameter is a pointer to the SQLite database connection that is executing
     /// the CREATE VIRTUAL TABLE statement.
@@ -54,7 +55,7 @@ pub trait VTab<C: VTabCursor<Self>>: Sized {
     /// Determine the best way to access the virtual table.
     fn best_index(&self, info: &mut IndexInfo) -> Result<()>;
     /// Create a new cursor used for accessing a virtual table.
-    fn open(&self) -> Result<C>;
+    fn open(&self) -> Result<Self::Cursor>;
 }
 
 bitflags! {
@@ -180,9 +181,10 @@ impl<'a> IndexConstraintUsage<'a> {
 }
 
 /// Virtual table cursor trait.
-pub trait VTabCursor<V: VTab<Self>>: Sized {
+pub trait VTabCursor: Sized {
+    type Table: VTab;
     /// Accessor to the associated virtual table.
-    fn vtab(&self) -> &V;
+    fn vtab(&self) -> &Self::Table;
     /// Begin a search of a virtual table.
     fn filter(&mut self, idx_num: c_int, idx_str: Option<&str>, args: &Values) -> Result<()>;
     /// Advance cursor to the next row of a result set initiated by `filter`.

src/vtab/series.rs

@@ -60,7 +60,9 @@ struct SeriesTab {
 }
 
 
-impl VTab<SeriesTabCursor> for SeriesTab {
+impl VTab for SeriesTab {
+    type Cursor = SeriesTabCursor;
+
     unsafe fn connect(db: *mut ffi::sqlite3,
                _aux: *mut c_void,
                _args: &[&[u8]])
@@ -171,7 +173,9 @@ impl SeriesTabCursor {
         Default::default()
     }
 }
-impl VTabCursor<SeriesTab> for SeriesTabCursor {
+impl VTabCursor for SeriesTabCursor {
+    type Table = SeriesTab;
+
     fn vtab(&self) -> &SeriesTab {
         unsafe { & *(self.base.pVtab as *const SeriesTab) }
     }