singleton docs

core/classes/classes-docs.factor

@@ -47,6 +47,7 @@ $nl
 "Other sorts of classes:"
 { $subsection "builtin-classes" }
 { $subsection "unions" }
+{ $subsection "singletons" }
 { $subsection "mixins" }
 { $subsection "predicates" }
 "Classes can be inspected and operated upon:"

core/classes/singleton/singleton-docs.factor

@@ -1,6 +1,11 @@
 USING: help.markup help.syntax kernel words ;
 IN: classes.singleton
 
+ARTICLE: "singletons" "Singleton classes"
+"A singleton is a class with only one instance and with no state.  Methods may dispatch off of singleton classes."
+{ $subsection POSTPONE: SINGLETON: }
+{ $subsection define-singleton-class } ;
+
 HELP: SINGLETON:
 { $syntax "SINGLETON: class"
 } { $values
@@ -8,7 +13,16 @@ HELP: SINGLETON:
 } { $description
     "Defines a new predicate class whose superclass is " { $link word } ".  Only one instance of a singleton may exist because classes are " { $link eq? } " to themselves.  Methods may be defined on a singleton."
 } { $examples
-    { $example "USING: singleton kernel io ;" "SINGLETON: foo\nGENERIC: bar ( obj -- )\nM: foo bar drop \"a foo!\" print ;\nfoo bar" "a foo!" }
+    { $example "USING: classes.singleton kernel io ;" "SINGLETON: foo\nGENERIC: bar ( obj -- )\nM: foo bar drop \"a foo!\" print ;\nfoo bar" "a foo!" }
 } { $see-also
     POSTPONE: PREDICATE:
 } ;
+
+HELP: define-singleton-class
+{ $values { "word" "a new word" } }
+{ $description
+    "Defines a newly created word to be a singleton class." } ;
+
+{ POSTPONE: SINGLETON: define-singleton-class } related-words
+
+ABOUT: "singletons"