Refactor usages of Next().

blob.go

@@ -52,6 +52,7 @@ type ZeroBlobLength int
 //  // check err
 //
 // Calls http://sqlite.org/c3ref/blob_open.html
+// TODO A real 'incremental' example...
 func (c *Conn) NewBlobReader(db, table, column string, row int64) (*BlobReader, error) {
 	bl, err := c.blob_open(db, table, column, row, false)
 	if err != nil {

meta.go

@@ -27,18 +27,19 @@ func (c *Conn) Databases() (map[string]string, error) {
 	}
 	defer s.Finalize()
 	var databases map[string]string = make(map[string]string)
-	var ok bool
 	var name, file string
-	for ok, err = s.Next(); ok; ok, err = s.Next() {
+	for {
+		if ok, err := s.Next(); err != nil {
+			return nil, err
+		} else if !ok {
+			break
+		}
 		err = s.Scan(nil, &name, &file)
 		if err != nil {
 			return nil, err
 		}
 		databases[name] = file
 	}
-	if err != nil {
-		return nil, err
-	}
 	return databases, nil
 }
 
@@ -50,15 +51,19 @@ func (c *Conn) Tables() ([]string, error) {
 	}
 	defer s.Finalize()
 	var tables []string = make([]string, 0, 20)
-	var ok bool
 	var name string
-	for ok, err = s.Next(); ok; ok, err = s.Next() {
-		s.Scan(&name)
-		tables = append(tables, name)
+	for {
+		if ok, err := s.Next(); err != nil {
+			return nil, err
+		} else if !ok {
+			break
 		}
+		err = s.Scan(&name)
 		if err != nil {
 			return nil, err
 		}
+		tables = append(tables, name)
+	}
 	return tables, nil
 }
 
@@ -82,8 +87,12 @@ func (c *Conn) Columns(table string) ([]Column, error) {
 	}
 	defer s.Finalize()
 	var columns []Column = make([]Column, 0, 20)
-	var ok bool
-	for ok, err = s.Next(); ok; ok, err = s.Next() {
+	for {
+		if ok, err := s.Next(); err != nil {
+			return nil, err
+		} else if !ok {
+			break
+		}
 		c := Column{}
 		err = s.Scan(&c.Cid, &c.Name, &c.DataType, &c.NotNull, &c.DfltValue, &c.Pk)
 		if err != nil {
@@ -91,9 +100,6 @@ func (c *Conn) Columns(table string) ([]Column, error) {
 		}
 		columns = append(columns, c)
 	}
-	if err != nil {
-		return nil, err
-	}
 	return columns, nil
 }
 
@@ -113,10 +119,14 @@ func (c *Conn) ForeignKeys(table string) (map[int]*ForeignKey, error) {
 	}
 	defer s.Finalize()
 	var fks = make(map[int]*ForeignKey)
-	var ok bool
 	var id, seq int
 	var ref, from, to string
-	for ok, err = s.Next(); ok; ok, err = s.Next() {
+	for {
+		if ok, err := s.Next(); err != nil {
+			return nil, err
+		} else if !ok {
+			break
+		}
 		err = s.NamedScan("id", &id, "seq", &seq, "table", &ref, "from", &from, "to", &to)
 		if err != nil {
 			return nil, err
@@ -130,9 +140,6 @@ func (c *Conn) ForeignKeys(table string) (map[int]*ForeignKey, error) {
 		fk.From = append(fk.From, from)
 		fk.To = append(fk.To, to)
 	}
-	if err != nil {
-		return nil, err
-	}
 	return fks, nil
 }
 
@@ -151,8 +158,12 @@ func (c *Conn) Indexes(table string) ([]Index, error) {
 	}
 	defer s.Finalize()
 	var indexes []Index = make([]Index, 0, 5)
-	var ok bool
-	for ok, err = s.Next(); ok; ok, err = s.Next() {
+	for {
+		if ok, err := s.Next(); err != nil {
+			return nil, err
+		} else if !ok {
+			break
+		}
 		i := Index{}
 		err = s.Scan(nil, &i.Name, &i.Unique)
 		if err != nil {
@@ -160,9 +171,6 @@ func (c *Conn) Indexes(table string) ([]Index, error) {
 		}
 		indexes = append(indexes, i)
 	}
-	if err != nil {
-		return nil, err
-	}
 	return indexes, nil
 }
 
@@ -175,8 +183,12 @@ func (c *Conn) IndexColumns(index string) ([]Column, error) {
 	}
 	defer s.Finalize()
 	var columns []Column = make([]Column, 0, 5)
-	var ok bool
-	for ok, err = s.Next(); ok; ok, err = s.Next() {
+	for {
+		if ok, err := s.Next(); err != nil {
+			return nil, err
+		} else if !ok {
+			break
+		}
 		c := Column{}
 		err = s.Scan(nil, &c.Cid, &c.Name)
 		if err != nil {
@@ -184,9 +196,6 @@ func (c *Conn) IndexColumns(index string) ([]Column, error) {
 		}
 		columns = append(columns, c)
 	}
-	if err != nil {
-		return nil, err
-	}
 	return columns, nil
 }
 

sqlite.go

@@ -600,14 +600,15 @@ func (s *Stmt) BindByIndex(index int, value interface{}) error {
 }
 
 // Evaluate an SQL statement
+//
 // With custom error handling:
-//	var ok bool
-//	var err os.Error
-// 	for ok, err = s.Next(); ok; ok, err = s.Next() {
-//		err = s.Scan(&fnum, &inum, &sstr)
+//	for {
+//		if ok, err := s.Next(); err != nil {
+//			return nil, err
+//		} else if !ok {
+//			break
 //		}
-//	if err != nil {
-//		...
+//		err = s.Scan(&fnum, &inum, &sstr)
 //	}
 // With panic on error:
 // 	for Must(s.Next()) {
@@ -712,6 +713,7 @@ func (s *Stmt) ColumnType(index int) Type {
 // Scan result values from a query by name (name1, value1, ...)
 // Example:
 //	stmt, err := db.Prepare("SELECT 1 as id, 'test' as name")
+//	// TODO error handling
 //	defer stmt.Finalize()
 //	var id int
 //	var name string
@@ -749,6 +751,7 @@ func (s *Stmt) NamedScan(args ...interface{}) error {
 // Scan result values from a query
 // Example:
 //	stmt, err := db.Prepare("SELECT 1, 'test'")
+//	// TODO error handling
 //	defer stmt.Finalize()
 //	var id int
 //	var name string
@@ -1093,7 +1096,7 @@ func (s *Stmt) ReadOnly() bool {
 func (c *Conn) EnableLoadExtension(b bool) {
 	C.sqlite3_enable_load_extension(c.db, btocint(b))
 }
-// Load an xxtension
+// Load an extension
 // Calls http://sqlite.org/c3ref/load_extension.html
 func (c *Conn) LoadExtension(file string, proc ...string) error {
 	cfile := C.CString(file)
@@ -1133,11 +1136,9 @@ func (c *Conn) IntegrityCheck(max int, quick bool) error {
 		return err
 	}
 	defer s.Finalize()
-	ok, err := s.Next()
-	if err != nil {
+	if ok, err := s.Next(); err != nil {
 		return err
-	}
-	if !ok {
+	} else if !ok {
 		return errors.New("Integrity check failed (no result)")
 	}
 	msg, null := s.ScanText(0)

sqlite_test.go

@@ -130,7 +130,7 @@ func TestInsert(t *testing.T) {
 		t.Errorf("column count error: %d <> 1", columnCount)
 	}
 
-	if ok := Must(cs.Next()); !ok {
+	if !Must(cs.Next()) {
 		t.Fatal("no result for count")
 	}
 	var i int
@@ -193,7 +193,7 @@ func TestInsertWithStatement(t *testing.T) {
 	if !cs.ReadOnly() {
 		t.Errorf("update statement is not readonly")
 	}
-	if ok := Must(cs.Next()); !ok {
+	if !Must(cs.Next()) {
 		t.Fatal("no result for count")
 	}
 	var i int
@@ -216,7 +216,7 @@ func TestInsertWithStatement(t *testing.T) {
 		t.Errorf("column name error: %s <> 'int_num'", secondColumnName)
 	}
 
-	if ok := Must(rs.Next()); ok {
+	if Must(rs.Next()) {
 		var fnum float64
 		var inum int64
 		var sstr string
@@ -231,7 +231,7 @@ func TestInsertWithStatement(t *testing.T) {
 			t.Errorf("Expected 'hello' <> %s\n", sstr)
 		}
 	}
-	if ok := Must(rs.Next()); ok {
+	if Must(rs.Next()) {
 		var fnum float64
 		var inum int64
 		var sstr string
@@ -320,7 +320,7 @@ func TestScanColumn(t *testing.T) {
 		t.Fatalf("prepare error: %s", err)
 	}
 	defer s.Finalize()
-	if ok := Must(s.Next()); !ok {
+	if !Must(s.Next()) {
 		t.Fatal("no result")
 	}
 	var i1, i2, i3 int
@@ -353,7 +353,7 @@ func TestNamedScanColumn(t *testing.T) {
 		t.Fatalf("prepare error: %s", err)
 	}
 	defer s.Finalize()
-	if ok := Must(s.Next()); !ok {
+	if !Must(s.Next()) {
 		t.Fatal("no result")
 	}
 	var i1, i2, i3 int