Pass Object from magic function

Question

I need to use TStringList in dwscript.

In compiled delphi code I use both

sl := TStringList.Create;

and

sl := genSL;

where genSL creates and poulates the TStringList.

I would like to use this in dwscript but I have trouble returning a TStringList from genSL.

Apparently there are two approaches.

1 using RTTI

In delphi I write

dwsUnit1.Dependencies.Add(RTTI_UnitName);
dwsUnit1.Functions.Add('genSL', 'RTTIVariant');

and in the callback

procedure TMainForm.genSLEval(info: TProgramInfo);
var
  sl: TStringList;
begin
  sl := TStringList.Create;
  // populate sl    
  Info.ResultAsVariant := TdwsRTTIVariant.FromObject(sl);
end;

This does allow my the pass an externally created TStringList into the script.

Problem: In the script I need to declare the list as RTTIVariant.

This is misleading as it actually is a TStringList (also I would like to use existing code without modification). I would prefer to declare the List as TStringList in the script.

2 Exposing TStringList to dwsUnit

In delphi I write

dwsUnit1.ExposeClassToUnit(TPersistent, TObject);
dwsUnit1.ExposeClassToUnit(TStrings, TPersistent);
dwsUnit1.ExposeClassToUnit(TStringList, TStrings);

In the script I can create and use TStringList.

But I can't declare a magic function that returns something TStringList-y

delphi code:

dwsUnit1.Functions.Add('genSL', 'TStringList');

and scriptcode:

var sl: TStringList;
sl := genSL;

Problem: this will abort script compilation with Syntax Error: Incompatible types: Cannot assign "TStringList" to "TStringList"

I assume I'm missing something. What is necessary to either

• Declare an Object as something other than RTTIVariant to pass objects to it

or

• Introduce a type so it can be passed into the script?

I'm using Delphi 2010 with dwscript-svn checked out back in 2013-07 (recent svn didn't compile in d2010). Any suggestions are appreciated.