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Why is my code not compiling, but rather getting E2506. A parameterized type method declared in an interface section must not use a local character

I am using Delphi XE.

The following module cannot compile this error:

[DCC Error] GTSJSONSerializer.pas(27): E2506 Method of parameterized type declared 
   in interface section must not use 
   local symbol 'TSuperRttiContext.AsJson<GTSJSONSerializer.TGTSJSONSerializer<T>.T>'

Why? Is there any workaround?

unit GTSJSONSerializer;

interface

type
   TGTSJSONSerializer<T> = class
     class function SerializeObjectToJSON(const aObject: T): string;
     class function DeserializeJSONToObject(const aJSON: string): T;
   end;

implementation

uses
        SuperObject
      ;

class function TGTSJSONSerializer<T>.SerializeObjectToJSON(const aObject: T): string;
var
  SRC: TSuperRttiContext;
begin
  SRC := TSuperRttiContext.Create;
  try
    Result := SRC.AsJson<T>(aObject).AsString;
  finally
    SRC.Free;
  end;
end;

class function TGTSJSONSerializer<T>.DeserializeJSONToObject(const aJSON: string): T;
var
  LocalSO: ISuperObject;
  SRC: TSuperRttiContext;
begin
  SRC := TSuperRttiContext.Create;
  try
    LocalSO :=  SO(aJSON);
    Result := SRC.AsType<T>(LocalSO);
  finally
    SRC.Free;
  end;
end;

end.
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2 answers

From the XE2 DocWiki :

This occurs when trying to assign a literal value to a generic data field.

program E2506;

{$APPTYPE CONSOLE}

uses
  SysUtils;

type
  TRec<T> = record
  public
    class var x: Integer;
    class constructor Create;
  end;

class constructor TRec<T>.Create;
begin
  x := 4; // <-- e2506 Fix: overload the Create method to 
          // take one parameter x and assign it to the x field.
end;

begin
   Writeln('E2506 Method of parameterized type declared' +
           ' in interface section must not use local symbol');
end.

, , ; SerialObjectToJSON DeserializeJSONToObject. , , , . TSuperRTTIContext?

+4

D2010, DXE DXE2 SuperObject 46.

+1

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