diff --git a/js/ast.go b/js/ast.go
index 929a515..a9608f5 100644
--- a/js/ast.go
+++ b/js/ast.go
@@ -1194,6 +1194,8 @@ func (n BindingArray) String() string {
 			s += ","
 		}
 		s += " ...Binding(" + n.Rest.String() + ")"
+	} else if 0 < len(n.List) && n.List[len(n.List)-1].Binding == nil {
+		s += ","
 	}
 	return s + " ]"
 }
@@ -1203,9 +1205,14 @@ func (n BindingArray) JS(w io.Writer) {
 	w.Write([]byte("["))
 	for j, item := range n.List {
 		if j != 0 {
-			w.Write([]byte(", "))
+			w.Write([]byte(","))
+		}
+		if item.Binding != nil {
+			if j != 0 {
+				w.Write([]byte(" "))
+			}
+			item.JS(w)
 		}
-		item.JS(w)
 	}
 	if n.Rest != nil {
 		if len(n.List) != 0 {
@@ -1213,6 +1220,8 @@ func (n BindingArray) JS(w io.Writer) {
 		}
 		w.Write([]byte("..."))
 		n.Rest.JS(w)
+	} else if 0 < len(n.List) && n.List[len(n.List)-1].Binding == nil {
+		w.Write([]byte(","))
 	}
 	w.Write([]byte("]"))
 }
diff --git a/js/ast_test.go b/js/ast_test.go
index eeab979..c879b5b 100644
--- a/js/ast_test.go
+++ b/js/ast_test.go
@@ -118,6 +118,7 @@ func TestJS(t *testing.T) {
 		{"{};;", "{} ;"},
 		{"{}\n;", "{} ;"},
 		{"- - --3", "- - --3;"},
+		{"([,,])=>P", "([,,]) => { return P; };"},
 	}
 
 	re := regexp.MustCompile("\n *")