prism/examples/prism-n4js.html

<h2>Keywords</h2>
<pre><code>
class C {..}
interface I {..}

foo(c: C, i: I) {
    c instanceof C; // ok
    c instanceof I; // ok
}
</code></pre>

<h2>Annotations</h2>
<pre><code>
// Final Methods
@Final
private tasks = new Map&lt;string,Task&gt;();

// Redefinition of Members
@Override
public async size(): int {
  …
}

// Dependency Injection
@Binder
@Bind(Storage,StorageInMemory)
class InMemoryBinder {}

@GenerateInjector @UseBinder(InMemoryBinder)
export public class TaskManagerTest {
  …
}
</code></pre>

<h2>Full example</h2>
<pre><code>
// A Web User Interface in HTML
// NOTE: requires full example project bundled with N4JS IDE to run.

import { TaskManager } from "TaskManager";
import {Application, Response } from "express";
import express from "express";
import { Todo } from "model";


export class WebUI {

     private app: Application;

     @Inject
     private manager: TaskManager;

     public start() {

          this.app = express();

          this.app.get('/', async (req, res) => {
               let page = await this.renderHomePage();
               res.send(page);
          });

          this.app.get("/clear", async (req, res) => {
               await this.manager.clear();
               redirect(res, '/');
          });

          this.app.get("/create", async (req, res) => {
               let values = req.query as ~Object with {type: string, label: string};
               if (values && values.type === 'Todo' && values.label && values.label.length > 0) {
                    await this.manager.createTodo(values.label);
               }
               redirect(res, '/');
          });

          this.app.listen(4000, '0.0.0.0', 511, function() {
               console.log("HTML server listening on http://localhost:4000/");
          });
     }

     protected async renderHomePage(): string {
          let tasks = await this.manager.getTasks();
          let todos = tasks.filter((task) => task instanceof Todo);
          return `

&lt;html&gt;
&lt;body&gt;
     Your to-do's:
     &lt;ul&gt;
     ${
          todos.length === 0 ? '&lt;li&gt;&lt;em&gt;none&lt;/em&gt;&lt;/li&gt;\n'
          : todos.map((task) =>
               '&lt;li&gt;' + task.label + ' &lt;small&gt;(id: ' + task.id + ')&lt;/small&gt;&lt;/li&gt;'
          ).join('\n')
     }
     &lt;/ul&gt;
     &lt;hr/&gt;
     &lt;form action="/create" method="get"&gt;
     &lt;input type="hidden" name="type" value="Todo"&gt;
     Label: &lt;input type="text" name="label"&gt;&lt;br&gt;
     &lt;input type="submit" value="Create Todo"&gt;
     &lt;/form&gt;
     &lt;hr/&gt;
     &lt;a href="/clear"&gt;[Clear All]&lt;/a&gt;
&lt;/body&gt;
&lt;/html&gt;
`;
     }
}

function redirect(res: Response, url: string) {
     res.header('Cache-Control', 'no-cache');
     res.redirect(301, url);
}
</code></pre>