docs(createGlobalState): add an example without persistence (#1991) (#…

…2114)

packages/shared/createGlobalState/index.md

@@ -9,6 +9,51 @@ Keep states in the global scope to be reusable across Vue instances.
 
 ## Usage
 
+### Without Persistence (Sotre in Memory)
+
+```js
+// store.js
+import { ref } from 'vue'
+import { createGlobalState } from '@vueuse/core'
+
+export const useGlobalState = createGlobalState(
+  () => {
+    const count = ref(0)
+    return { count }
+  }
+)
+```
+
+A bigger example:
+
+```js
+// store.js
+import { computed, ref } from 'vue'
+import { createGlobalState } from '@vueuse/core'
+
+export const useGlobalState = createGlobalState(
+  () => {
+    // state
+    const count = ref(initialValue)
+
+    // getters
+    const doubleCount = computed(() => count.value * 2)
+
+    // actions
+    function increment() {
+      count.value++
+    }
+
+    return { count, doubleCount, increase }
+  }
+)
+```
+
+
+### With Persistence
+
+Store in `localStorage` with `useStorage()`:
+
 ```js
 // store.js
 import { createGlobalState, useStorage } from '@vueuse/core'