turned spaced helper into a extension

lib/pages/create_post.dart

@@ -8,8 +8,8 @@ import '../hooks/logged_in_action.dart';
 import '../hooks/memo_future.dart';
 import '../hooks/stores.dart';
 import '../util/extensions/api.dart';
+import '../util/extensions/spaced.dart';
 import '../util/goto.dart';
-import '../util/spaced.dart';
 import '../widgets/markdown_text.dart';
 import 'full_post.dart';
 
@@ -197,7 +197,7 @@ class CreatePost extends HookWidget {
       ),
       body: SafeArea(
         child: Column(
-          children: spaced(6, [
+          children: [
             instanceDropdown,
             communitiesDropdown,
             url,
@@ -226,7 +226,7 @@ class CreatePost extends HookWidget {
                 )
               ],
             ),
-          ]),
+          ].spaced(6),
         ),
       ),
     );

lib/util/extensions/spaced.dart

@@ -0,0 +1,9 @@
+import 'package:flutter/cupertino.dart';
+
+/// Creates gaps between given widgets
+extension SpaceWidgets on List<Widget> {
+  List<Widget> spaced(double gap) => expand((item) sync* {
+        yield SizedBox(width: gap, height: gap);
+        yield item;
+      }).skip(1).toList();
+}

lib/util/spaced.dart

@@ -1,10 +0,0 @@
-import 'package:flutter/cupertino.dart';
-
-/// Creates gaps between given widgets
-List<Widget> spaced(double gap, Iterable<Widget> children) => children
-    .expand((item) sync* {
-      yield SizedBox(width: gap, height: gap);
-      yield item;
-    })
-    .skip(1)
-    .toList();