A.M. Hoornweg

Sure it is documented. But it may be off the radar that existing binaries such as DLL's may suddenly behave differently if they were written in Delphi. I use some third-party DLL's that were written in Delphi.

As far as I can see you can't download from that site though.

I am getting "Disconnected Session" all the time whilst working on a 64-bit project. Never had this problem in 12.0. The error dialog window contains this information: [69E0B1C0]{dbkdebugide290.bpl} Debug.TDebugKernel.msgBox (Line 5951, "Debug.pas" + 30) + $0 [2BCC6EB3]{bordbk290.dll} Unknown function at DllUnregisterServer + $5037 [2BD3B88C]{bordbk290.dll} Unknown function at @isDbkLoggingOn$qv + $619B4 [2BD3B90B]{bordbk290.dll} Unknown function at @isDbkLoggingOn$qv + $61A33 [2BD3C351]{bordbk290.dll} Unknown function at @isDbkLoggingOn$qv + $62479 [2BD3C5A1]{bordbk290.dll} Unknown function at @isDbkLoggingOn$qv + $626C9 [2BD6C3D3]{bordbk290.dll} Unknown function at @isDbkLoggingOn$qv + $924FB [69E0B6FD]{dbkdebugide290.bpl} Debug.TThread.DoGetCurAddr (Line 6080, "Debug.pas" + 1) + $4 [2BCD9D72]{bordbk290.dll} Unknown function at DllUnregisterServer + $17EF6 [2BD6A91D]{bordbk290.dll} Unknown function at @isDbkLoggingOn$qv + $90A45 [2BD3C577]{bordbk290.dll} Unknown function at @isDbkLoggingOn$qv + $6269F [2BD3C7E0]{bordbk290.dll} Unknown function at @isDbkLoggingOn$qv + $62908 [2BCC6A4B]{bordbk290.dll} Unknown function at DllUnregisterServer + $4BCF [2BD5AB32]{bordbk290.dll} Unknown function at @isDbkLoggingOn$qv + $80C5A [2BD5AB3C]{bordbk290.dll} Unknown function at @isDbkLoggingOn$qv + $80C64 [69E17AFD]{dbkdebugide290.bpl} Debug.GetNextEvent (Line 11764, "Debug.pas" + 1) + $24 [6DC6037A]{rtl290.bpl } System.@IsClass (Line 18904, "System.pas" + 1) + $8 [69E185E1]{dbkdebugide290.bpl} Debug.TDebugger.UpdateEventLog (Line 11776, "Debug.pas" + 9) + $1 [69E11931]{dbkdebugide290.bpl} Debug.TProcess.ntfyNewEventLogData (Line 9020, "Debug.pas" + 1) + $7 [2BD5B3A0]{bordbk290.dll} Unknown function at @isDbkLoggingOn$qv + $814C8 [2BD3B90B]{bordbk290.dll} Unknown function at @isDbkLoggingOn$qv + $61A33 [2BD3C577]{bordbk290.dll} Unknown function at @isDbkLoggingOn$qv + $6269F [2BD570FB]{bordbk290.dll} Unknown function at @isDbkLoggingOn$qv + $7D223 [2BD57136]{bordbk290.dll} Unknown function at @isDbkLoggingOn$qv + $7D25E [2BD6C4C7]{bordbk290.dll} Unknown function at @isDbkLoggingOn$qv + $925EF [2BCD9D72]{bordbk290.dll} Unknown function at DllUnregisterServer + $17EF6 [2BD3B8B0]{bordbk290.dll} Unknown function at @isDbkLoggingOn$qv + $619D8 [2BD3C7E0]{bordbk290.dll} Unknown function at @isDbkLoggingOn$qv + $62908 [2BCE4247]{bordbk290.dll} Unknown function at @isDbkLoggingOn$qv + $A36F [625AA5EA]{CnWizards_D120A.DLL} Unknown function at __dbk_fcall_wrapper + $788AA [6CB305FD]{vcl290.bpl } Vcl.Themes.TStyleHook.WndProc (Line 7733, "Vcl.Themes.pas" + 38) + $6 [6CC598FC]{vcl290.bpl } Vcl.Styles.TStyleEngine.HandleMessage (Line 3616, "Vcl.Styles.pas" + 20) + $C [6340DEA9]{mmx_bds23.dll} IDEEdtHooks.GetMessageHook (Line 66, "IDEEdtHooks.pas" + 7) + $12 [6279DE04]{CnWizards_D120A.DLL} Unknown function at INITWIZARD0001 + $17CC00 [6CB7392F]{vcl290.bpl } Vcl.Forms.TApplication.ProcessMessage (Line 13284, "Vcl.Forms.pas" + 25) + $1 [6CB73952]{vcl290.bpl } Vcl.Forms.TApplication.ProcessMessages (Line 13304, "Vcl.Forms.pas" + 1) + $4 [00487F2B]{bds.exe } AppMain.TAppBuilder.ApplicationActivated + $7 [6CBCD24F]{vcl290.bpl } Vcl.AppEvnts.TCustomApplicationEvents.DoActivate (Line 210, "Vcl.AppEvnts.pas" + 1) + $16 [6CBCD8ED]{vcl290.bpl } Vcl.AppEvnts.TMultiCaster.DoActivate (Line 438, "Vcl.AppEvnts.pas" + 5) + $10 [6CB72DD0]{vcl290.bpl } Vcl.Forms.TApplication.WndProc (Line 12854, "Vcl.Forms.pas" + 140) + $C [6DD8477C]{rtl290.bpl } System.Classes.StdWndProc (Line 19085, "System.Classes.pas" + 9) + $2 [6CB73927]{vcl290.bpl } Vcl.Forms.TApplication.ProcessMessage (Line 13282, "Vcl.Forms.pas" + 23) + $1 [6CB7396A]{vcl290.bpl } Vcl.Forms.TApplication.HandleMessage (Line 13312, "Vcl.Forms.pas" + 1) + $4 [6CB73CA9]{vcl290.bpl } Vcl.Forms.TApplication.Run (Line 13451, "Vcl.Forms.pas" + 27) + $3 [004D8AD2]{bds.exe } bds.bds + $DE

There are ways to achieve that (passing an EMF cross-process) but yes, it would be ugly. It would be like re-inventing the RDP protocol.

If you'd ask me to attempt a thing like that, I'd first look for a suitable bidirectional RPC framework. Something having capabilities like COM. COM was used by IDE's such as Visual Basic to host (in-process) VBX controls but it works across processes as well. The "helper processes" would only need to contain the designtime part of the components, at runtime they do nothing. Such an approach would move the design time components out of the address space of the IDE. Also, the "bitness" of the helper processes and the IDE would be independent from each other.

My preference would be to have the component packages in separate helper processes.

Please remember that all installed design time packages (BPL files) and their associated runtime packages must be compiled to the same architecture and bitness as the IDE itself. BPLs are just DLLs and the IDE loads them directly, in-process. This means that moving away from 32-bit x86 would be a huge breaking change for the deployment of third party components. Frankly, I've never understood why the design time packages are hosted in the IDE process itself because bugs in components will affect the IDE. Many of us will know the phenomenon that the IDE may throw an AV exception in some BPL when you terminate Delphi.

Can't you make a read-only property out of it instead of a plain method? That way you could make it show up in the watch list of the debugger.

No need for this, the debugger has that functionality built-in: -Set a breakpoint on your corner case condition and wait until it fires -Right-click the line where you want to "go to" -Enter submenu "Debug" -Select menu item "Set next statement". The debugger will jump here when you single-step through your code.

A thread using While not terminated do begin Dosomething; Sleep(xxx); end; is perfectly OK if the thread has to do something useful periodically and if xxx isn't a terribly small number. But if "Dosomething()" is merely polling for some state change to respond to, then it's rather inefficient to have this thread constantly wakeup, consume CPU time and sleep again. The "Sleep(xxx)" also limits the response time and the number of state changes that can be handled per second. For such a scenario it's much more efficient if you can wake up the thread "from the outside" ASAP when it has to react. This is where events really shine.

I would personally write such a program as a service application and let it monitor messages like WM_POWERBROADCAST to log the events. This way you can be sure that the application is always running and will capture the events when they happen.

Hello all, I see that the Delphi 12 source code formatter (Ctrl-D) still mutilates generic class declarations, it inserts inappropriate line feeds between keywords and ruins indentation. Is there a way to set markers in the source code that tell the formatter to skip those areas from formatting? Or can you recommend a better code formatter that handles generics properly? Have a nice day! Arthur

Hello all, suppose I have a generic class that's going to be inherited. I want to give the base class a method that creates a new instance of the same object type (a class factory so to speak). How can I do that? I need to somehow tell the compiler which constructor to call. Type tSomeclass<T:iInterface>=CLass (tInterfacedObject, iSomeInterface<T>) //many methods here Procedure SomeMethod(intf: T); Function SomeFunction:T; Constructor Create(someparameters); Function CreateNewInstance:iSomeInterface<T>; end; ... Function tSomeclass<T>.CreateNewInstance:iSomeInterface<T> begin result:=Self.Classtype.Create(fSomeParameters); //Does not compile end;

Thank you! That seems to work indeed !

The reason I'm trying to achieve this is the following. I have made a generic tStreamableInterfaceList<T:iInterface> which is basically a managed Tlist<T> that implements iInterfacelist<T>. The elements are interfaces. This list object knows several special tricks such as saving its contents to XML and BSON. It can also load those elements back from such data files, which necessitates a virtual ClassFactory() method to create the correct objects "on the fly" based on the class names found in the data. So far, this all works very nicely. I wanted to enhance this list with a few LinQ-like methods such as: Function .Where(aCondition:tPredicate<T>):iInterfacelist<T>; Function .OrderBy(aCompare:tComparison<T>):iInterfacelist<T>; ... but in order to achieve that, the base class must be able to dynamically instantiate derived classes or else the resulting objects would have the base nonfunctional Classfactory() method. The "ugly" solution would be to put an abstract virtual Clone() method in the base class, but I'd very much like to avoid that.

That doesn't do the trick, because function TMyClass<T>.CloneObject: TMyClass<T>; ... will just construct an instance of the base class, I would have to re-implement that method in each derived class. With non-generic classes it is possible to achieve what I want (see below). With generics, the "class of..." syntax does not work. type SomeClassType = class of tSomeClass; tSomeClass = class protected SomeNumber: Integer; public constructor Create(aSomeNumber: Integer); virtual; function Copy: tSomeClass; procedure Whoami; end; tSomeClass2=Class(tSomeClass) End; tSomeClass3=Class(tSomeClass2) End; function tSomeClass.Copy: tSomeClass; var ctype: SomeClassType; begin ctype := SomeClassType(self.ClassType); result := ctype.Create(SomeNumber+1); end; constructor tSomeClass.Create(aSomeNumber: Integer); begin inherited Create; SomeNumber := aSomeNumber; end; procedure tSomeClass.Whoami; begin OutputDebugString(pchar( format('Class name = %s, number is %d',[self.classname,somenumber] ))); end; procedure TForm1.Button2Click(Sender: TObject); begin tSomeclass3.Create(1).Copy.Copy.Copy.Whoami; //yes, this test leaks some memory. end;

Hello all, I'm using Delphi 12 enterprise and in this version I'm unable to create regions using the IDE context menu because the menu item surround is grayed out. What could have caused it and how can I re-enable it?

Eh what, the internal IDE source code formatter is deprecated? Are they just abandoning it without any replacement? I find it rather essential.

tSearchrec is a record that contains a managed type (the file name is a string). When managed types go out of scope, the code generated by the compiler checks if they are no longer in use and that any heap memory they occupy is freed properly. That costs time.

You misinterpret my idea. OP merely used power() and rounding to demonstrate that 32- and 64 bit code do not have identical FP accuracy. Unfortunately people think in decimal digits and want those represented and rounded accurately. I simply recommend to use a fixed point numeric variable type for storage if this is the purpose and if the number of decimals is <=4. A soon as there is a FP calculation involved there is the risk that the result (a double, single or extended) isn't an exact representation anymore. But still, replacing "double" by "currency" in OP's example produces the expected result in both 32 and 64 bit mode.

I wouldn't. But I certainly do have a use for fixed comma numbers that must be compared for exactness. As in being part of the composite primary key of a database table. So I cherish the fact that this numeric type can be tested with exactness.

One would only do this if one wants to convert floating point numbers to fixed point numbers. Fixed point numbers can be compared with exactness and there are use cases for that.

If the number of decimal places is not greater than 4, OP might consider using the currency data type. Currencies are exact fixed-point numbers having four decimals after the dot so a value like 1.015 can be stored with perfect precision. Adding, subtracting and comparing currencies always gives an exact result. Internally, they are 64-bit signed integers with an implicit divisor of 10,000. [edit] functions like "power" return a double or extended. Prior to comparing the results of such functions, store them in currencies.

Or write a tiny command line program that scans a dfm file and removes that property. Run that program prior to committing code to your source code repository. TortoiseSVN allows you to fully automate this by setting "hooks", I don't know about Git.

OP needs 300 billion bits or so he said. I assume that collecting that amount of data takes a long time and that the data will be evaluated to obtain some sort of useful result afterwards. So the program must run for a long time and may not be terminated prematurely or else the contents of the tBits are lost and everything has to start over again. That sounds like a very time consuming development/debugging cycle that can be avoided by splitting up the program into an acquisition process and an evaluation process that share a common block of virtual memory. The acquisition part can run "forever" in the background, it can be straightforward because it needs not evaluate the results. It just supplies live data (bits) in memory that become more complete over time. The evaluation part can be a work in progress that can be comfortably debugged, refined and re-compiled. It can observe "live" data that become more complete over time.