This document discusses different patterns for invoking functions and setting the value of 'this' in JavaScript. It covers: the method invocation pattern where 'this' refers to the object containing the method; the function invocation pattern where 'this' defaults to the global object; the constructor invocation pattern where 'this' refers to a new object created; and the apply invocation pattern where 'this' is explicitly set as the first parameter of the apply method.

1. JavaScript
The good parts for humans
(part 3)
B Anjaneyulu Reddy
Email: anji.t6@gmail.com
Twitter: @_anji
www.evibe.in

2. Agenda
Day 2 revisit
this property
arguments property

3. Method invocation pattern
method: function stored as a property
this - object containing method
late binding
Sample 1

4. Function invocation pattern
this - global object [design mistake]
inner functions this: refers to global object
var that = this
Sample 2

5. Constructor invocation pattern
functions invoked with new prefix
this - new object created
no explicit return value - this is returned
hidden link to function's prototype
Sample 3

6. Apply invocation pattern
apply method
• two parameters
o value for this
o array of parameters
this - first parameter of apply
Sample 4

7. Questions?

8. Thank You