diff --git a/lib/src/tuple.dart b/lib/src/tuple.dart
index 13c89d3..15cc2c9 100644
--- a/lib/src/tuple.dart
+++ b/lib/src/tuple.dart
@@ -38,7 +38,7 @@
   ///
   /// The elements are in item order. The list is variable-length
   /// if [growable] is true.
-  List toList({bool growable: false}) =>
+  List toList({bool growable = false}) =>
       new List.from([item1, item2], growable: growable);
 
   @override
@@ -94,7 +94,7 @@
   ///
   /// The elements are in item order. The list is variable-length
   /// if [growable] is true.
-  List toList({bool growable: false}) =>
+  List toList({bool growable = false}) =>
       new List.from([item1, item2, item3], growable: growable);
 
   @override
@@ -159,7 +159,7 @@
   ///
   /// The elements are in item order. The list is variable-length
   /// if [growable] is true.
-  List toList({bool growable: false}) =>
+  List toList({bool growable = false}) =>
       new List.from([item1, item2, item3, item4], growable: growable);
 
   @override
@@ -237,7 +237,7 @@
   ///
   /// The elements are in item order. The list is variable-length
   /// if [growable] is true.
-  List toList({bool growable: false}) =>
+  List toList({bool growable = false}) =>
       new List.from([item1, item2, item3, item4, item5], growable: growable);
 
   @override
@@ -336,7 +336,7 @@
   ///
   /// The elements are in item order. The list is variable-length
   /// if [growable] is true.
-  List toList({bool growable: false}) =>
+  List toList({bool growable = false}) =>
       new List.from([item1, item2, item3, item4, item5, item6],
           growable: growable);