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6.1.2 Creating Objects with new

6.1.2 Creating Objects with new


The newoperator creates and initializes a new object. The newkeyword must be followed by a function invocation. A function used in this way is called a constructor and serves to initialize a newly created object. Core JavaScript includes built-in constructors for native types. For example:

var o = new Object(); // Create an empty object: same as {}. var a = new Array(); // Create an empty array: same as []. var d = new Date(); // Create a Date object representing the current time var r = new RegExp("js"); // Create a RegExp object for pattern matching.

In addition to these built-in constructors, it is common to define your own constructor functions to initialize newly created objects. Doing so is covered in Chapter 9 .

6.1 Creating Objects | 117

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