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(Singleton)
(Intent)
(Motivation)
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(Applicability)
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(Structure)
(Participants)
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(Collaborations)
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(consequences)
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(Implementation)
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TSingleton = class public constructor Create; virtual; destructor Destroy; override; end; var Glob_Singleton1: TSingleton;//
implementation
constructor TSingleton.Create; begin if Glob_Singleton1 <> nil then abort else Glob_Singleton1 := Self; end;
destructor TSingleton.Destroy; begin if Glob_Singleton1 = self then Glob_Singleton1 := nil; inherited Destroy; end; Delphi /0IJ Glob_Singleton1 à_ Singleton , È xP !~Çk Ó ¦§¡ Tsingleton %,^_ }Ó ÈÚyz½ Create ¹JijæIJP C¡ È /0 ºIJM ²o ÈÆ ¶·89WX a
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type TSingletonList = class(TList);
TSingletonl = class public constructor Create;virtual; destructor Destroy; override; protected function Lookup(PSingleton: TSingletonl): boolean; end;
TChildSingletonl = class(TSingletonl);
var Glob_Singletonlist: TSingletonList; //
implementation
L Lookup()¹Jb Ó 1 plSingleton.ClassName = PSingleton.ClassNametD/¦§ TSingleton TChildSingletonl = class(TSingletonl)P8&EFĬ îÄÈ }$P8F ÄG HIJvKY%a
(Sample Code)
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(Known uses)
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(Related Patterns)
&'e%, Singleton uCMNOP(Abstract Factory)Q`¸ (Builder)QR(Prototype) 2000/12/ http://home.kimo.com.tw/areca_chen/
