Custom function registered to DWScript and support nested parameters and nested eval?

[wqmeng]

Hello,

I have try to add my custom functions such as Func_A, Func_B and Func_C to DWScript and use them in a Script. By adding TdwsFunction, It seems not work well with nested paramters eval.

          LFunc := Self.dwsUnit.Functions.Add;
          LFunc.Name := 'Func_A';
          LFunc.Overloaded := true;
          LFunc.ResultType := 'Integer';
          LFunc.OnEval := dwsUnitFunctions_Func_A_Eval;   //
          LFunc.Parameters.Add('P1', 'String');
          LFunc.Parameters.Add('P2', 'String');
          LFunc.Parameters.Add('P3', 'Integer');

If the above function Func_A, I would like to call it in script as Func_A(Func_B, Func_C, 10); And even more nested as FuncA(Func_B + Func_C, 'Hello', .... , Seems that the parameter could not pass in as a Expression but a 'String'.

Should I use TFuncSymbol and assign a implmentation of the IExecutable to support the nest eval, or Should I use Something from dwsExprs such as TExprBase to support nested eval in my custom functions Func_A, ...?

Do you have a example to achieve it?

Thank you very much.