How to create unique automatic JavaScript objects (2/2)

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How To Create Unique Automatic JavaScript Objects

Why this works

In JavaScript a function is an object of type Function, and you can treat the function's name as a variable which references the function as an object. So you can give the function object custom properties, just as you can with any other object.

Why I gave the constructor's custom property such a strange name

The code on page 1 meets the requirement not to create any hard-coded global names. But it creates a custom property of the constructor function myObjectType. This creates two small risks of name conflicts:

• A future extension of the ECMAscript standard may add properties to the built-in Function object type, and I can't predict their names.
• A user who knows this technique may wish to create his / her own custom properties of constructor functions, and should not have to read through my code to avoid name conflicts.

So I try to minimize the risk of name conflicts in custom properties of standard objects by following these rules:

• names which are for internal use only begin with _ (underscore), a convention which has worked well in C for decades.
• the next part of the name is my initials, followed by a 2-letter code for the package of which the object is part. This reduces the risk of conflicts with custom properties created by other users who use the _ (underscore) convention--and with custom properties created by other scripts I write!

About the author

Philip Chalmers has worked in IT since the early 1970s (sometimes feels like the 1870s). He has specified, designed, and developed systems on platforms ranging from mainframes to PCs in several languages. His first technical publication appeared in 1979, when he wrote several sections of the Adabas DBA Manual.

You can email him or check out some of his other ideas at his Web site.

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Created: November 7, 2002
Revised: November 7, 2002

URL: https://webreference.com/programming/javascript/objects/2.html