28 lines
742 B
Factor
28 lines
742 B
Factor
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
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POSTPONE: SINGLETON:
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POSTPONE: SINGLETONS:
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define-singleton-class
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}
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"The set of all singleton classes is itself a class:"
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{ $subsections
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singleton-class?
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singleton-class
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} ;
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HELP: define-singleton-class
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{ $values { "word" "a new word" } }
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{ $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
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{ $class-description "The class of singleton classes." } ;
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ABOUT: "singletons"
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