c# - Generic Abstract Class -


i have following code fine...

namespace genericabstract {     public interface inotifmodel     {         string data { get; set; }     }      public interface inotif<t> t: inotifmodel     {        t model { get; set; }     }      public interface inotifprocessor<in t> t : inotif<inotifmodel>     {         void yell(t notif);     }      public class helloworldmodel : inotifmodel     {         public string data { get; set; }          public helloworldmodel()         {             data = "hello world!";         }     }      public class helloworldnotif : inotif<helloworldmodel>     {         public helloworldmodel model { get; set; }          public helloworldnotif()         {             model = new helloworldmodel();         }     }      public class helloworldprocessor<t> : inotifprocessor<t> t : inotif<inotifmodel>     {         public void yell(t notif)         {             throw new notimplementedexception();         }     } }

as can see there 3 interfaces , each of implemented.

however, processor implemented this:

public class helloworldprocessor : inotifprocessor<helloworldnotif<helloworldmodel>> {     public void yell(helloworldnotif<helloworldmodel> notif)     {         throw new notimplementedexception();     } }

but following error:

the non-generic type 'helloworldnotif' cannot used type arguments

i want helloworldprocessor implement inotifprocessor helloworldnotif...

can't figure out doing wrong..

for work first have make inotif<t> co-variant. means model property has read interface (it can still have public set in implementation). fix immediate error don't put <helloworldmodel> after helloworldnotif because it's inotif<helloworldmodel>

public interface inotifmodel {     string data { get; set; } }  public interface inotif<out t> t : inotifmodel {     t model { get; } }  public interface inotifprocessor<in t> t : inotif<inotifmodel> {     void yell(t notif); }  public class helloworldmodel : inotifmodel {     public string data { get; set; }      public helloworldmodel()     {         data = "hello world!";     } }  public class helloworldnotif : inotif<helloworldmodel> {     public helloworldmodel model { get; set; }      public helloworldnotif()     {         model = new helloworldmodel();     } }  public class helloworldprocessor<t> : inotifprocessor<t> t : inotif<inotifmodel> {     public void yell(t notif)     {         throw new notimplementedexception();     } }  public class helloworldprocessor : inotifprocessor<helloworldnotif> {     public void yell(helloworldnotif notif)     {         throw new notimplementedexception();     } }

then guess implementation 

console.writeline(notif.model.data);

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