function-patterns/self-defining-functions.html

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		<title>JavaScript Patterns</title>
		<meta charset="utf-8">
	</head>
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		<script>
			/* Title: Self-defining functions
			 Description: self-overwrite with new bodies to do less work from the second invocation and after
			 */

			var scareMe = function () {
				alert("Boo!");
				scareMe = function () {
					alert("Double boo!");
				};
			};

			// 1. adding a new property
			scareMe.property = "properly";
			// 2. assigning to a different name
			var prank = scareMe;
			// 3. using as a method
			var spooky = {
				boo:scareMe
			};
			// calling with a new name
			prank(); // "Boo!"
			prank(); // "Boo!"
			console.log(prank.property); // "properly"
			// calling as a method
			spooky.boo(); // "Boo!"
			spooky.boo(); // "Boo!"
			console.log(spooky.boo.property); // "properly"
			// using the self-defined function
			scareMe(); // Double boo!
			scareMe(); // Double boo!
			console.log(scareMe.property); // undefined
		</script>
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