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    <p>I'm not sure why you get that error. The following seems to work for me, in Delphi XE:</p> <pre><code>program Project1; {$APPTYPE CONSOLE} uses SysUtils, Classes, Contnrs, Generics.Defaults, Generics.Collections, DbxJson, DbxJsonReflect; type TTestObject = class(TObject) aList : TStringList; function Marshal : TJSonObject; public constructor Create; destructor Destroy; override; end; TTestObjectList&lt;T:TTestObject,constructor&gt; = class(TObjectList&lt;T&gt;) function Marshal: TJSonObject; constructor Create; end; { TTestObject } constructor TTestObject.Create; begin inherited Create; aList := TStringList.Create; aList.Add('one'); aList.Add('two'); aList.Add('three'); end; destructor TTestObject.Destroy; begin aList.Free; inherited; end; function TTestObject.Marshal: TJSonObject; var Marshal: TJSONMarshal; begin Marshal := TJSONMarshal.Create(TJSONConverter.Create); try Marshal.RegisterConverter(TStringList, function (Data: TObject): TListOfStrings var I, Count: Integer; begin Count := TStringList(Data).Count; SetLength(Result, Count); for I := 0 to Count - 1 do Result[I] := TStringList(Data)[I]; end ); Result := Marshal.Marshal(Self) as TJSONObject; finally Marshal.Free; end; end; { TTestObjectList&lt;T&gt; } constructor TTestObjectList&lt;T&gt;.Create; begin inherited Create; Add(T.Create); Add(T.Create); end; function TTestObjectList&lt;T&gt;.Marshal: TJSonObject; var Marshal: TJsonMarshal; begin Marshal := TJSONMarshal.Create(TJSONConverter.Create); try Marshal.RegisterConverter(TTestObject, function (Data: TObject): TObject begin Result := T(Data).Marshal; end ); Result := Marshal.Marshal(Self) as TJSONObject; finally Marshal.Free; end; end; procedure Main; var aTestobj : TTestObject; aList : TTestObjectList&lt;TTestObject&gt;; aJsonObject : TJsonObject; begin aTestObj := TTestObject.Create; aJsonObject := aTestObj.Marshal; Writeln(aJsonObject.ToString); Writeln; aList := TTestObjectList&lt;TTestObject&gt;.Create; aJsonObject := aList.Marshal; Writeln(aJsonObject.ToString); Readln; end; begin try Main; except on E: Exception do begin ExitCode := 1; Writeln(Format('[%s] %s', [E.ClassName, E.Message])); end; end; end. </code></pre>
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    1. POGenerics and Marshal / UnMarshal. What am I missing here?
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    1. USOndrej Kelle
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    1. POGenerics and Marshal / UnMarshal. What am I missing here?
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    1. VO
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    2. VO
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      1. VTUpMod
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    1. COJust tried your code in XE - and I must admit. It works. I'll have to try some more complex things with it. Give me a couple of hours and I'll get back. I want to investigate with a bit bigger project - to see if the problem occurs.
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    2. COHi again.. sry for the delay. I've now tested the code in XE2 ... and it fails exactly as my code do ???? Perhaps there is a problem with marshalling in XE2 ? I'm new to generics - and the way you include the constructor in the type declaration is absolutely brilliant. Just for that I'm willing to accept you code as an answer - even that it only work in XE :-)
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    3. COThe problem is now promoted to QC#99313. With the code example from TOndrej.
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