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										 |  |  | USING: help.markup help.syntax kernel words ;
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										 |  |  | IN: classes.singleton | 
					
						
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										 |  |  | ARTICLE: "singletons" "Singleton classes" | 
					
						
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										 |  |  | "A singleton is a class with only one instance and with no state." | 
					
						
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										 |  |  | { $subsections | 
					
						
							|  |  |  |     POSTPONE: SINGLETON: | 
					
						
							|  |  |  |     POSTPONE: SINGLETONS: | 
					
						
							|  |  |  |     define-singleton-class | 
					
						
							|  |  |  | } | 
					
						
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										 |  |  | "The set of all singleton classes is itself a class:" | 
					
						
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										 |  |  | { $subsections | 
					
						
							|  |  |  |     singleton-class? | 
					
						
							|  |  |  |     singleton-class | 
					
						
							|  |  |  | } ;
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							|  |  |  | HELP: define-singleton-class | 
					
						
							|  |  |  | { $values { "word" "a new word" } } | 
					
						
							|  |  |  | { $description | 
					
						
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										 |  |  |     "Defines a singleton class. This is the run-time equivalent of " { $link POSTPONE: SINGLETON: } "." } ;
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							|  |  |  | { POSTPONE: SINGLETON: define-singleton-class } related-words | 
					
						
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										 |  |  | HELP: singleton-class | 
					
						
							|  |  |  | { $class-description "The class of singleton classes." } ;
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										 |  |  | ABOUT: "singletons" |