implement

examples/react-example1/src/App.js

@@ -1,6 +1,6 @@
 import React from "react";
 import Subspace from "@status-im/subspace";
-import { $average, $max, $min } from "@status-im/subspace";
+import { $average, $max, $min, $latest } from "@status-im/subspace";
 import { map } from 'rxjs/operators';
 import ProductComponent from "./ProductComponent";
 import web3 from './web3';
@@ -32,6 +32,7 @@ class App extends React.Component {
       averageRating: rating$.pipe($average()),
       minRating: rating$.pipe($min()),
       maxRating: rating$.pipe($max()),
+      last5Ratings: rating$.pipe($latest(5)),
       balance: subspace.trackBalance(Product.options.address)
     });
   }
@@ -66,6 +67,7 @@ class App extends React.Component {
           minRating={this.state.minRating}
           averageRating={this.state.averageRating}
           balance={this.state.balance}
+          last5Ratings={this.state.last5Ratings}
         />
       </div>
     );

examples/react-example1/src/ProductComponent.js

@@ -1,17 +1,21 @@
 import React from "react";
 import { observe } from "@status-im/subspace/react";
 
-const ProductComponent = ({ maxRating, minRating, averageRating, title, balance }) => {
+const ProductComponent = ({ maxRating, minRating, averageRating, title, balance, last5Ratings }) => {
   // Handle initial state when no data is available
   // if (!maxRating && !minRating && !averageRating) {
     // return <p>No data</p>;
   // }
 
+  console.dir("last5Ratings")
+  console.dir(last5Ratings)
+
   return <ul>
     <li><b>title: </b> {title}</li>
     <li><b>minimum rating: </b> {minRating}</li>
     <li><b>maximum rating: </b> {maxRating}</li>
     <li><b>average rating: </b> {averageRating}</li>
+    <li><b>last 5 ratings: </b> {(last5Ratings || []).join(', ')}</li>
     <li><b>balance in contract:</b> {balance}</li>
   </ul>;
 };

src/operators.js

@@ -71,11 +71,6 @@ export function $min(cb) {
       } else {
         currentValue = curr;
       }
-      console.dir("===========");
-      console.dir(currentValue);
-      console.dir(acc);
-      console.dir(currentValue <= acc);
-      console.dir("===========");
 
       if (currentValue < acc) return currentValue;
       return acc;
@@ -83,6 +78,21 @@ export function $min(cb) {
   );
 }
 
+export function $latest(num) {
+  return pipe(
+    scan((acc, curr) => {
+      let currentValue = curr;
+
+      acc.push(currentValue)
+      if (acc.length > num) {
+        acc.shift()
+      }
+
+      return acc;
+    }, [])
+  );
+}
+
 /*
 of(10, 3, 4)
   .pipe($average())