On Fri, May 14, 2010 at 11:45 AM, Graeme Geldenhuys <graemeg.li...@gmail.com> wrote: > Hi, > > I tried using FPC 2.5.1 today to see how compatible is our application with > it compared to FPC 2.4.1 > > I got stacks of the following errors. Why is this change forced in FPC > 2.5.1? TBulkInvoiceRateListForm class is a descendant of TfpgWindowBase so > there should be a problem. I don't understand. :-/ > > ------------- > frm_bulkinvoiceratelist.pas(84,77) Error: Call by var for arg no. 2 has to > match exactly: Got "TBulkInvoiceRateListForm" expected "TfpgWindowBase" > fpg_base.pas(2207,31) Hint: Found declaration: > TfpgApplicationBase.CreateForm(TComponentClass,out TfpgWindowBase); > frm_bulkinvoiceratelist.pas(307) Fatal: There were 1 errors compiling > module, stopping > -------------------- > > > To get my code to compile again, I have to change the following code from > > fpgApplication.CreateForm(TBulkInvoiceRateListForm, BulkDiscountListForm); > > ...to this... > > fpgApplication.CreateForm(TBulkInvoiceRateListForm, > TfpgWindowBase(BulkDiscountListForm)); > > Now I have to include ugly casts all over the place. :-( > > > I got similar issues with TStrings and TStringList. TStringList is a > descendant of TStrings, but I can't pass a TStringList type as a parameter > to a method declared with TStrings. > > > Maybe I don't understand the var parameter correctly (but haven't tested to > see what happens if I remove var from parameter list). If I have a class > instance, when should I pass it to a method or function/procedure as var > and when don't I need to use var parameters? > > > > Regards, > - Graeme - > > --
I thought this feature was an improvement over Delphi too. But IIRC the argumentation was that it generated confusion, as somebody could think a reintroduced method would be invoked instead of the base one. I guess there was some other more compelling reason, but I can't remember right now, but I'm positive this was already brought up on the list. Best regards, Flávio _______________________________________________ fpc-devel maillist - fpc-devel@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-devel
