Merge pull request #151 from yezyilomo/update_docs

Update documentation

website/docs/api_reference/high_level_api/store.subscribe.md

@@ -40,4 +40,14 @@ store.getState(key).subscribe({
     })
 })
 ```
-With this observer function will only be called when the selected state changes
+With this observer function will only be called when the selected state changes.
+
+
+Another way to subscribe to nested state or derived state is to call `select` on a global state then subscribe to it as
+
+```js
+store.getState(key).select(state => selected_state).subscribe(value =>{
+        // Do your thing here
+    }
+)
+```

website/docs/api_reference/low_level_api/createGlobalState.md

@@ -40,6 +40,16 @@ Some of the methods available in a global state object are `getValue`, `updateVa
   // Signature
   globalState.subscribe(observer: Function | Subscription: {observer, selector});
   ```
+- `select`: This is used to derive another state or select a deeply nested state
+  ```js
+  // Signature
+  globalState.select(selector: Function);
+  ```
+  This returns `DerivedGlobalState` that you can subscribe to by calling `subscribe` on it as
+  ```js
+  // Signature
+  globalState.select(selector: Function).subscribe(observer: Function);
+  ```
 
 Below is an example showing all of them in action
 ```js
@@ -51,12 +61,19 @@ count.getValue()  // This will give 0
 
 count.setValue(1)  // This set the value of count to 1
 
-count.updateValue(val => val+1)  // This will increment the value of count
-
 // This will print whenever count change
 const unsubscribe = count.subscribe(val => console.log(val)) 
 
 unsubscribe()  // This will unsubscribe the observer above
+
+// An example for nested state
+const user = createGlobalState({name: "Yezy", weight: 65});
+
+user.updateValue(user => {user.weight += 1})  // This will increment the weight
+
+// Select user name and subscribe to it,
+// this will be printing whenever user name changes
+user.select(user => user.name).subscribe(name => console.log(name));
 ```
 
 

website/docs/basic_concepts/derived_state.md

@@ -3,7 +3,7 @@ sidebar_position: 3
 ---
 
 # Derived & Nested State
-With state pool you can subscribe to deeply nested global state or a derived state. Both `store.useState` and `store.useReducer` accepts an optional configuration parameter with which you can pass `selector` & `patcher` options that are used to derive and update state.
+With state pool you can subscribe to deeply nested or derived state. Both `store.useState` and `store.useReducer` accepts an optional configuration parameter with which you can pass `selector` & `patcher` options that are used to derive and update state.
 
 Here is a simple example showing how to use `selector` & `Patcher` options
 

website/docs/basic_concepts/managing_subscriptions.md

@@ -40,4 +40,14 @@ store.getState(key).subscribe({
     })
 })
 ```
-With this, observer function will only be called when the selected state changes
+With this, observer function will only be called when the selected state changes.
+
+
+Another way to subscribe to nested state or derived state is to call `select` on a global state then subscribe to it as
+
+```js
+store.getState(key).select(state => selected_state).subscribe(value =>{
+        // Do your thing here
+    }
+)
+```