Updates to chapter 1 and 2.

code/hp-react.js

@@ -1,3 +1,16 @@
+var Hello = ({ dateTime }) => {
+    return ['h1', {}, [`It is: ${dateTime}`]];
+};
+
+var App = () => {
+    return ['div', { 'className': 'header' },
+            [Hello({ dateTime: new Date() }),
+             ['input', { 'type': 'submit', 'disabled': 'disabled' }, []]
+            ]
+           ];
+}
+
+
 var d =
 ['div', { 'className': 'header' },
   [['h1', {}, ['Hello']],
@@ -126,3 +139,10 @@ function renderChildren(element, domElement, prevElement = { props: { children:
         return render_internal(child, domElement, prevChild);
     });
 }
+
+
+
+var Hello = memo(({ dateTime }) => {
+    return ['h1', {}, [`It is: ${dateTime}`]];
+});
+