Minor optim.

function.go

@@ -376,8 +376,8 @@ type sqliteFunction struct {
 	final      FinalFunction
 	d          DestroyDataFunction
 	pApp       interface{}
-	scalarCtxs map[*ScalarContext]bool
-	aggrCtxs   map[*AggregateContext]bool
+	scalarCtxs map[*ScalarContext]struct{}
+	aggrCtxs   map[*AggregateContext]struct{}
 }
 
 //export goXAuxDataDestroy
@@ -400,7 +400,7 @@ func goXFunc(scp, udfp, ctxp unsafe.Pointer, argc int, argv unsafe.Pointer) {
 		c.udf = udf
 		C.goSqlite3SetAuxdata((*C.sqlite3_context)(c.sc), 0, unsafe.Pointer(c))
 		// To make sure it is not cged
-		udf.scalarCtxs[c] = true
+		udf.scalarCtxs[c] = struct{}{}
 	}
 	c.argv = (**C.sqlite3_value)(argv)
 	udf.scalar(c, argc)
@@ -420,7 +420,7 @@ func goXStep(scp, udfp unsafe.Pointer, argc int, argv unsafe.Pointer) {
 			c.sc = (*Context)(scp)
 			*(*unsafe.Pointer)(cp) = unsafe.Pointer(c)
 			// To make sure it is not cged
-			udf.aggrCtxs[c] = true
+			udf.aggrCtxs[c] = struct{}{}
 		} else {
 			c = (*AggregateContext)(p)
 		}
@@ -476,7 +476,7 @@ func (c *Conn) CreateScalarFunction(functionName string, nArg int, deterministic
 			fmt.Sprintf("<Conn.CreateScalarFunction(%q)", functionName))
 	}
 	// To make sure it is not gced, keep a reference in the connection.
-	udf := &sqliteFunction{f, nil, nil, d, pApp, make(map[*ScalarContext]bool), nil}
+	udf := &sqliteFunction{f, nil, nil, d, pApp, make(map[*ScalarContext]struct{}), nil}
 	if len(c.udfs) == 0 {
 		c.udfs = make(map[string]*sqliteFunction)
 	}
@@ -500,7 +500,7 @@ func (c *Conn) CreateAggregateFunction(functionName string, nArg int, pApp inter
 			fmt.Sprintf("<Conn.CreateAggregateFunction(%q)", functionName))
 	}
 	// To make sure it is not gced, keep a reference in the connection.
-	udf := &sqliteFunction{nil, step, final, d, pApp, nil, make(map[*AggregateContext]bool)}
+	udf := &sqliteFunction{nil, step, final, d, pApp, nil, make(map[*AggregateContext]struct{})}
 	if len(c.udfs) == 0 {
 		c.udfs = make(map[string]*sqliteFunction)
 	}

vtab.go

@@ -22,13 +22,13 @@ type sqliteModule struct {
 	c      *Conn
 	name   string
 	module Module
-	vts    map[*sqliteVTab]bool
+	vts    map[*sqliteVTab]struct{}
 }
 
 type sqliteVTab struct {
 	module *sqliteModule
 	vTab   VTab
-	vtcs   map[*sqliteVTabCursor]bool
+	vtcs   map[*sqliteVTabCursor]struct{}
 }
 
 type sqliteVTabCursor struct {
@@ -65,9 +65,9 @@ func goMInit(db, pClientData unsafe.Pointer, argc int, argv **C.char, pzErr **C.
 	vt := &sqliteVTab{m, vTab, nil}
 	// prevents 'vt' from being gced
 	if m.vts == nil {
-		m.vts = make(map[*sqliteVTab]bool)
+		m.vts = make(map[*sqliteVTab]struct{})
 	}
-	m.vts[vt] = true
+	m.vts[vt] = struct{}{}
 	*pzErr = nil
 	return unsafe.Pointer(vt)
 }
@@ -101,9 +101,9 @@ func goVOpen(pVTab unsafe.Pointer, pzErr **C.char) unsafe.Pointer {
 	// prevents 'vt' from being gced
 	vtc := &sqliteVTabCursor{vt, vTabCursor}
 	if vt.vtcs == nil {
-		vt.vtcs = make(map[*sqliteVTabCursor]bool)
+		vt.vtcs = make(map[*sqliteVTabCursor]struct{})
 	}
-	vt.vtcs[vtc] = true
+	vt.vtcs[vtc] = struct{}{}
 	*pzErr = nil
 	return unsafe.Pointer(vtc)
 }