add simple store

src/store/index.js

@@ -0,0 +1,27 @@
+class Store {
+  constructor(reducer, catcher) {
+    this.reducer = reducer;
+    this.catcher = catcher;
+    this.state = this.reducer(undefined, {});
+  }
+
+  dispatch(action) {
+    if (action instanceof Promise) {
+      action.then((a) => {
+        this.state = this.reducer(this.state, a);
+      }).catch(this.catcher)
+    } else {
+      try {
+        this.state = this.reducer(this.state, action);
+      } catch (e) {
+        this.catcher(e);
+      }
+    }
+  }
+}
+
+const empty = () => {};
+
+export function createStore(reducer, catcher = empty) {
+  return new Store(reducer, catcher);
+}