Delphi

function TfrmMain.CopyVarRec(const Item: TVarRec): TVarRec;
begin
  // Copy entire TVarRec first.
  Result := Item;

  // Now handle special cases.
  case Item.VType of
    vtExtended:
      begin
        New(Result.VExtended);
        Result.VExtended^ := Item.VExtended^;
      end;
    vtPChar:
      begin
        Result.VPChar := StrNew(Item.VPChar);
      end;
    // A little trickier: casting to string will ensure
    // reference counting is done properly.
    vtAnsiString:
      begin
        // Nil out first, so no attempt to decrement
        // reference count.
        Result.VAnsiString := nil;
        string(Result.VAnsiString) := string(Item.VAnsiString);
      end;
  end;
end;

// TVarRecs created by CopyVarRec must be finalized with this function.
// You should not use it on other TVarRecs.
procedure TfrmMain.FinalizeVarRec(var Item: TVarRec);
begin
  case Item.VType of
    vtExtended: Dispose(Item.VExtended);
    vtString: Dispose(Item.VString);
    // vtAnsiString uses reference counting.
  end;
  Item.VInteger := 0;
end;

Result.VAnsiString := nil;