Primitive Data Types, Arrays, Loops, and Conditions

Comments

One last thing for this chapter: comments. Inside your JavaScript code you can put comments. These are ignored by the JavaScript engine and don't have any effect on how the program works. But they can be invaluable when you revisit your code after a few months, or transfer the code to someone else for maintenance.

Two types of comments are allowed:

Single line comments—start with // and end at the end of the line
Multi-line comments—start with /* and end with */ on the same line or any subsequent line. Note that any code in between the comment start and the comment end will be ignored.

Some examples:

// beginning of line
var a = 1; // anywhere on the line
/* multi-line comment on a single line */	
/* 
    comment
    that spans
    several lines
 */

There are even utilities, such as JSDoc, that can parse your code and extract meaningful documentation based on your comments.

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Object-Oriented JavaScript

Object-Oriented JavaScript

Overview of this book

Comments

Object-Oriented JavaScript

Object-Oriented JavaScript

Overview of this book

Comments

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