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Lars Fosdal

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Lars Fosdal last won the day on October 12

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  • Delphi-Version
    Delphi 10.3 Rio

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  1. Lars Fosdal

    LiveBinding at runtime

    We already had something else doing the job for us, so we had no need to transition to it. The fragile bit can be only be eliminated when we get a NameOf compiler magic function.
  2. Lars Fosdal

    Interesting article about dying languages

    Jack of all trades, master of none - seems to be my modus operandi, which is more or less the same as sucking equally at everything 😉
  3. Lars Fosdal

    LiveBinding at runtime

    Live bindings were dead to me after a short test. Fragile and slow was not a winning combo.
  4. It probably disappeared when they introduced TListHelper. GetList returns arrayofT(FListHelper.FItems);
  5. Lars Fosdal

    Azure Key Vault support

    Feel free to vote for https://quality.embarcadero.com/browse/RSP-26400 if you need Azure Key Vault support for your Delphi/C++Builder projects.
  6. Lars Fosdal

    How to get Linux installed?

    It is truly tragic that Linux is not available for the Pro SKU. It should even have been in the Community version IMO. Imagine the potential plethora of code coming from open source projects.
  7. Lars Fosdal

    Interesting article about dying languages

    https://larsfosdal.blog/2019/10/10/most-popular-programming-languages-1965-2019/ Stumbled on a nice video showing the rise and fall of Pascal and Delphi. That said, like Cobol, Delphi will take a looong time disappearing.
  8. Lars Fosdal

    Add a system-menu item to all applications?

    Adulthood is overrated.
  9. OK, that makes sense. But - it is a bit of a pitfall, since you can call virtual methods from the static one - and not get a warning about it.
  10. The output of the test app below surprised me. Can someone point me to the documentation that says that if a static class method calls a virtual class method, only the base class virtual method will be called, and not the override? TParent.HasOverride: I said no to overrides TParent.HasOverride Static: I said no to overrides TChild.HasOverride: I haz overridez TChild.HasOverride Static: I said no to overrides Press Enter: program StaticClassMethodCallingVirtualClassMethod; {$APPTYPE CONSOLE} {$R *.res} uses System.SysUtils; type TParent = class public class function OverrideMe: Boolean; virtual; class function HasOverride: string; class function HasOverrideStatic: string; static; class procedure Test<T: TParent, constructor>; end; TChild = class(TParent) public class function OverrideMe: Boolean; override; end; { TParent } class function TParent.HasOverride: string; begin if OverrideMe then Result := 'I haz overridez' else Result := 'I said no to overrides'; end; class function TParent.HasOverrideStatic: string; begin if OverrideMe then Result := 'I haz overridez' else Result := 'I said no to overrides'; end; class function TParent.OverrideMe: Boolean; begin Result := False; end; class procedure TParent.Test<T>; begin Writeln(T.ClassName, '.HasOverride: '^I^I, T.HasOverride); Writeln(T.ClassName, '.HasOverride Static: '^I, T.HasOverrideStatic); end; { TChild } class function TChild.OverrideMe: Boolean; begin Result := True; end; begin try try TParent.Test<TParent>; TParent.Test<TChild>; except on E: Exception do Writeln(E.ClassName, ': ', E.Message); end; finally Write('Press Enter: '); Readln; end; end.
  11. I considered XMLDoc, but compile and runtime validation won out.
  12. Pawel, Enums are not the problem. Using helper classes, these are trivial to deal with. Constants that are strings or records are, as is the fact that constants don't have RTTI info. Stefan, the problem with the parser is that it would be near impossible to catch everything since we are talking about a class hierarchy with multiple inheritance branches, and I'd spend more time tinkering with the parser, than manually maintaining explicit output. The current approach is not perfect, but it does make it nearly automatic to keep the API docs up to date and document the source code at the same time. The best formal way would probably be to define it all in Swagger, but ... yeah... not intended for public consumption. An example of how I use RTTI to produce documentation from types and attributes to the various fields, here is a sample of one of the API calls for one of our JsonRPC servers, which is generated (once) at runtime from code. All Json samples are generated using the actual objects, so that changes are reflected whenever something is added/removed/changed. procedure TDoc_TPGMission.Login; begin Method(TLoginRequest); BuildExample<TLoginRequest, TLoginResult>( procedure (const Json:TLoginRequest) begin Json.params.step := TPGStep.S01_Login.AsString; Json.params.username := 'picavi'; Json.params.password := ' ... '; Json.params.clientId := 'Glass-1'; Json.params.deviceType := 'Glass'; Json.params.truckId := 'T011'; end, procedure (const Json: TLoginResult) begin Json.sessionIdent := SessIdent; json.configuration.language := 'NO'; json.configuration.mode := 'professional-superuser'; end, ['Fully qualified login. See below for partially qualified logins.'], -32990, 'Login failed', 'Wrong username [<username>]'); BuildExample<TLoginRequest, TLoginResult>( procedure (const Json:TLoginRequest) begin Json.params.step := TPGStep.S01_Login.AsString; Json.params.clientId := 'Glass-1'; end, procedure (const Json: TLoginResult) begin Json.sessionIdent := SessIdent; json.userList.Add('usrid1', 'foslar', 'Lars Fosdal'); json.userList.Add('usrid2', 'krujon', 'Jonas Krueckels'); json.truckList.Add('T011', 'Truck 11', 'Four slot pick truck'); json.truckList.Add('T012', 'Truck 12', 'Four slot pick truck'); json.truckList.Add('ADIDAS', 'Walking', 'Picker walks without truck'); json.missionList.Add('PICKX', 'X Pick', 'Regular picking at Area X'); json.missionList.Add('PICKY', 'Y Pick', 'Regular picking at Area Y'); json.missionList.Add('SMALL', 'Bag Picking', 'Pick small bag deliveries'); json.Result := False; end, ['Partially qualified login. Missing id(s) will cause an error, but will instead return result.result as False.', 'This means each of the lists has to be inspected to see what was missing', 'and the appropriate input or selection must be done by the user.', 'As long as the login request is missing information, it will "loop" until the login is qualified.', 'Erroneous information should yield an error.'], -32990, 'Login failed', 'Wrong username [<username>]'); end; I use attributes in the Json objects to add a short description of each property. TLoginParams = class(TSessionParams) strict private FdeviceType: string; FclientId: string; Fusername: string; [Encrypted] Fpassword: string; FmissionId: string; Flanguage: string; Fmode: string; Fprotocol: integer; FareaId: string; public class function RPCName:String; override; class function PropDoc(const aPropName: string): string; override; constructor Create; override; function DeviceClient:String; [Doc('Device Type')] property deviceType: string read FdeviceType write FdeviceType; [Doc('Client identifier ')] property clientId: string read FclientId write FclientId; [Doc('User short name')] property username: string read Fusername write Fusername; [Doc('Password')] property password: string read Fpassword write Fpassword; [Doc('UI Language, supported languages: "EN" for English, "NO" for Norwegian, "SE" for Swedish')] property language: string read Flanguage write Flanguage; [Doc('UI Mode - deprecated - should always be "professional"')] property mode: string read Fmode write Fmode; // 'Professional' 'Normal' 'Professional-SuperUser' 'Normal-SuperUser' [Doc('Mission Identity')] property missionId: string read FmissionId write FmissionId; [Doc('Pick area identity (Pick zone)')] property areaId: string read FareaId write FareaId; [Doc('Supported device protocol level')] /// <summary> Supported device protocol level </summary> property protocol: Integer read Fprotocol write Fprotocol; end; TLoginRequest = class(TJsonRPCRequest<TLoginParams>); One exception is an Error code table, which has to be handcrafted and manually updated, since the numerical error codes must be constant. Here is an excerpt: TDispatchError = record // NB! Update procedure TDoc_TPGMission.ErrorCodes in TPG.JsonRPC.Dispatcher when adding error codes private const LoginError = -32900; TUError = -33100; LocationError = -33200; ArticleError = -33300; SaldoError = -33400; MissionError = -33500; SystemError = -33600; MethodError = -33700; SwapError = -33800; DBError = -40000; public const UnknownSession = LoginError - 1; NoDeviceType = LoginError - 2; UnsupportedDeviceType = LoginError - 3; NoDevice = LoginError - 4; InvalidDevice = LoginError - 5; InvalidTruck = LoginError - 6; InvalidMission = LoginError - 7; MethodNotImplemented = LoginError - 8; InvalidArea = LoginError - 70; OtherUserHasTruck = LoginError - 80; LoggedIntoAnotherTruck = LoginError - 81; InvalidUser = LoginError - 90; UserAlreadyLoggedIn = LoginError - 91; CallSuperUser = LoginError - 93; InvalidPassword = LoginError - 94; InvalidPINCode = LoginError - 95; StoragePositionFull = TUError - 1; TUNotFound = TUError - 2; MultipleTUsFound = TUError - 3; OrderSave = MissionError - 1; OrderLineSave = MissionError - 2; OrderRead = MissionError - 3; OrderLineRead = MissionError - 4; AlreadyAllocated = MissionError - 5; This is where I wish I could use NameOf(TDispatchError.Whatever) to get 'Whatever" and put attributes in front of the constant to add a description that I could extract with RTTI. procedure TDoc_TPGMission.ErrorCodes; begin Chapter('TPG Error Codes ', 'Error_Codes', 1); Title := 'All error codes are negative numbers and they are grouped into the following ranges.'; DocTableBegin(html.divStyle.detail); DocTableHeaders(['Error name', 'value', 'description']); DefTitle('Login Errors'); Def('UnknownSession', TDispatchError.UnknownSession); Def('NoDeviceType', TDispatchError.NoDeviceType); Def('UnsupportedDeviceType', TDispatchError.UnsupportedDeviceType); Def('NoDevice', TDispatchError.NoDevice); Def('InvalidDevice', TDispatchError.InvalidDevice); Def('InvalidTruck', TDispatchError.InvalidTruck); Def('InvalidMission', TDispatchError.InvalidMission); Def('MethodNotImplemented', TDispatchError.MethodNotImplemented); Def('InvalidArea', TDispatchError.InvalidArea); The TOC
  13. < wishful > I keep running into cases where I have to manually duplicate the name of a constant to register it for lookup, or associate the constant with a numeric ID which then is used for the lookup. Either method means double book keeping and is error prone. Some of it would be nicely handled by having a compiler magic NameOf method that could give me name of a constant, field or property as a string at compile time. In other cases it would have been awesome to be able to enumerate a class or a record and get the declared constant names, types and values. This particularly goes for types I want to document for f.x. a JsonRPC API. Instead, I have to manually emit that information, constant for constant, which means someone will eventually forget to do that. If only the compiler gods where listening... < / wishful >
  14. https://community.idera.com/developer-tools/b/blog/posts/gm-update?utm_source=Article&utm_medium=email&utm_content=Article-190924-GMUpdate See also Jim's blog https://community.idera.com/developer-tools/b/blog/posts/the-future-of-codecentral
  15. Lars Fosdal

    Search -> Go to Lne Number dialog

    Since I don't have an eidetic memory, I rarely use it, but I won't say that I never use it. I prefer bookmarks if I need to frequently jump between sections in a file.