[Improvement] add utils (#416)

example/pages/dashboard/index.js

@@ -1,14 +1,8 @@
-import config from '../../config';
+import list from '../../config';
 import Page from '../../common/page';
 
 Page({
   data: {
-    list: config
-  },
-
-  onShareAppMessage() {
-    return {
-      title: 'Vant Weapp 组件库演示'
-    };
+    list
   }
 });

packages/search/README.md

@@ -39,7 +39,7 @@ Search 支持自定义右侧取消按钮，使用名字为 action 的 slot 即
   use-action-slot
   @search="onSearch"
 >
-  <view slot="action" @click="onSearch">搜索</view>
+  <view slot="action" bind:tap="onSearch">搜索</view>
 </van-search>
 ```
 

packages/utils/index.js

@@ -0,0 +1,13 @@
+function isDef(value) {
+  return value !== undefined && value !== null;
+}
+
+function isObj(x) {
+  const type = typeof x;
+  return x !== null && (type === 'object' || type === 'function');
+}
+
+export {
+  isObj,
+  isDef
+};