fix

pkg/expr/mongo.go

@@ -213,6 +213,8 @@ func (c *compiler) UnaryNode(node *ast.UnaryNode) interface{} {
 
 func (c *compiler) identifier(node ast.Node) string {
 	switch l := node.(type) {
+	case *ast.MemberNode:
+		return c.MemberNode(l)
 	case *ast.IdentifierNode:
 		return c.IdentifierNode(l)
 	}
@@ -314,6 +316,14 @@ func (c *compiler) BinaryNode(node *ast.BinaryNode) interface{} {
 	}
 }
 
+func (c *compiler) MemberNode(node *ast.MemberNode) string {
+	v := c.compile(node.Node)
+	if val, ok := v.(string); ok {
+		return fmt.Sprintf("%s.%s", val, node.Property)
+	}
+	panic(fmt.Sprintf("unsupported property for %v", ast.Dump(node.Node)))
+}
+
 func (c *compiler) SliceNode(node *ast.SliceNode) interface{} {
 	panic("unsupported slice node")
 }