Wrapped events and added cheatsheet

Author: Ian-Read

cheatsheet/index.md

@@ -0,0 +1,17 @@
+# Node Cheat Sheet
+
+# <a name="Events"></a>Events
+
+Class: events.EventEmitter
+
+```
+emitter.addListener(event, listener)
+emitter.on(event, listener)
+emitter.once(event, listener)
+emitter.removeListener(event, listener)
+emitter.removeAllListeners([event])
+emitter.setMaxListeners(n)
+emitter.listeners(event)
+emitter.emit(event, [arg1], [arg2], [...])
+Event: 'newListener'
+```

events/index.md

@@ -3,9 +3,11 @@ layout: default.njk
 title: Events
 ---
 
+# Events
+
 The Node.js core API is built around the idea of events being "emitted" and "listened" to. Objects called "emitters" emit _named_ events, that are picked up by "listener" functions.
 
-Objects that emit events extend the `EventEmitter` class. These objects expose an eventEmitter.on() function that allows one or more functions to be attached to named events emitted by the object.
+Objects that emit events extend the `EventEmitter` class. These objects expose an `on` method that allows one or more functions to be attached to named events emitted by the object.
 
 When the EventEmitter object emits an event, all of the functions attached to that specific event are called _synchronously_, in the order they were added. This is to prevent race conditions and logic errors. They can switch to an async mode using `setImmediate`.
 
@@ -34,7 +36,9 @@ eventEmitter.emit('foo')
 
 ## Passing parameters
 
-When an event is emitted using the `emit` method, the subsequent arguments are passed through to the listeners. For example:
+When an event is emitted using the `emit` method, the subsequent arguments are passed through to the listeners.
+
+For example:
 
 ```
 const foo = function foo(bar) {
@@ -48,24 +52,16 @@ eventEmitter.on('foo', foo)
 eventEmitter.emit('foo', 'bar')
 ```
 
-## Objects:
-
-```
-require('events)
-```
-
-## Methods
-
-`on(eventName, listenerFunction)`
-
 ## Summary
 
-Main concept = listeners listen for events, that are emitted from emitters.
+Listeners _listen_ for events, that are _emitted_ from emitters.
 
-## Exercise
+Take me to [cheat sheet](../cheatsheet/#events)
 
-Image we are building a SaaS that does a number of things when a user creates an account.   functionality that sends emails "confirmation" to a user when they create an account.
+## Exercise
 
-There is a mock emailer class in the folder that has a method `send`, which expects an email address and a message body as the parameters.
+Imagine we are building a SaaS that does a number of things when a user creates an account. When a user record
+is created, we want to emit a `userCreated` event. One of the listeners for this will email a confirmation
+email to that user.
 
-Use this to send a welcome email when a `userCreated` event is fired.
+Build an event emitter to simulate the `userCreated` event, and an event listener that sends a confirmation email. There is a mock emailer class in the folder that has a method `send`, which expects an email address and a message body as the parameters.

index.md

@@ -9,3 +9,6 @@ TODO:
 
 - Set out the purpose here and list the sections with links
 - Styling and update the default template
+
+
+[Events](/events)