Built-in Objects | Object-Oriented JavaScript

Function

JavaScript functions are objects. They can be defined using the Function constructor, like so:

>>> var sum = new Function('a', 'b', 'return a + b;');

This is equivalent to the function literal:

>>> var sum = function(a, b){return a + b;};

or the more common:

>>> function sum(a, b){return a + b;}

The use of the Function constructor is discouraged in favor of the function literals.

Members of the Function Objects

Property/Method	Description
`apply(this_obj, params_array)`	Allows you to call another function while overwriting its `this` value. The first parameter that `apply()` accepts is the object to be bound to `this` inside the function and the second is an array of parameters to be passed to the function being called. function whatIsIt(){ return this.toString(); } >>> var myObj = {}; >>> whatIsIt.apply(myObj); "[object Object]" >>> whatIsIt.apply(window); "[object Window]"
`call(this_obj, p1, p2, p3, ......`

Property/Method

Description

apply(this_obj, params_array)

Allows you to call another function while overwriting its this value. The first parameter that apply() accepts is the object to be bound to this inside the function and the second is an array of parameters to be passed to the function being called.

function whatIsIt(){
  return this.toString();
}
>>> var myObj = {};
>>> whatIsIt.apply(myObj);

"[object Object]"

>>> whatIsIt.apply(window);

"[object Window]"

call(this_obj, p1, p2, p3, ......

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Object-Oriented JavaScript

By : Stoyan STEFANOV

Object-Oriented JavaScript

By: Stoyan STEFANOV

Overview of this book

Function

Members of the Function Objects

Object-Oriented JavaScript

By : Stoyan STEFANOV

Object-Oriented JavaScript

By: Stoyan STEFANOV

Overview of this book

Function

Members of the Function Objects

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