Originally created by: palej

Can there be ENUM in STRUCT? Because I'am getting a weird error from my library saying Instance of reference...

I am just trying to make a simple struct DUT for logging

TYPE sLogEvent :
STRUCT
LogID : WORD;
LogTime: DATE_AND_TIME;
LogType: ErrorLevelType;
LogMessage: STRING(100);
END_STRUCT
END_TYPE

If I comment out the LogType, it works, but with it, it doesn't:

{attribute 'qualified_only'}
{attribute 'strict'}
TYPE ErrorLevelType :
(
NoError := 0,
Debug := 1,
Info := 2,
Warning := 3,
Error := 4,
Critical := 5
) := NoError;
END_TYPE

What I am doing wrong?

Thank you

I've added these 2 DUT's and used both and I'm not getting any errors. Do you have more code available or is this already causing an error?

Originally created by: palej

I have builded this in Codesys library, then "Save Project as Compiled library" -> then used the compiled library in other project in Network Variable List:

EH_EventLog: MyCommonLibrary.sLogEvent;

And when build my project, it says that error. If I comment out those two ENUMs from the MyCommonLibrary and save as compiled library and update the library file from my other project, the error is gone?

Because your enum is in your library also I believe you need to include the library name.

TYPE sLogEvent :
STRUCT
LogID : WORD;
LogTime: DATE_AND_TIME;
LogType: MyCommonLibrary.ErrorLevelType;
LogMessage: STRING(100);
END_STRUCT
END_TYPE

Originally created by: palej

They are in same library. And I still did try that, and it doesn't recognize the library name when it is in it's own library.

Any solution available for this?

I'm in kind of the same situation, when adding custom library structs (containing enums) to a network variable lists, compiling is not completed

The 2 devices exchanging the NVL is in the same project, and the library is installed in the POU library manager.
Linking the NVL to a external file makes no difference.
If i change the enums to INT, compile is completed with no errors.

[ERROR]         Internal error:System.NullReferenceException: The object reference is not set to an instance of an object.
ved _3S.CoDeSys.ApplicationObject.NetVarPDOList.AddVariable(String stVarName, IType type, IPrecompileScope scope, ApplicationObject appl, IVariable var, String& stError, HashSet`1 hsRecursionCheck)
ved _3S.CoDeSys.ApplicationObject.NetVarPDOList.AddVariable(String stVarName, IType type, IPrecompileScope scope, ApplicationObject appl, IVariable var, String& stError, HashSet`1 hsRecursionCheck)
ved _3S.CoDeSys.ApplicationObject.NetVarManager.AddObject(NetVarObject nwObject, String& stError)
ved _3S.CoDeSys.ApplicationObject.NetVarProtocol.AddObject(NetVarObject nwObject, String& stError)    ved _3S.CoDeSys.ApplicationObject.NetVarLanguageModel.AddObject(NetVarObject nwObject)
ved _3S.CoDeSys.ApplicationObject.ApplicationObject.AddNetVarLanguageModel(XmlWriter xmlwriter)
ved _3S.CoDeSys.ApplicationObject.ApplicationObject.GetLanguageModel()
ved _3S.CoDeSys.ApplicationObject.ApplicationObject.GetStructuredLanguageModel(ILanguageModelBuilder lmbuilder)
ved _3S.CoDeSys.LanguageModelManager.LanguageModelManagerConsolidated.PutLanguageModel(ILanguageModelProvider lanmodprov, Boolean bShowSyntaxErrors, Boolean forceCompleteLanguageModel)
ved _3S.CoDeSys.ApplicationObject.ApplicationObject.OnBeforeCompile(Object sender, CompileEventArgs e)    ved _3S.CoDeSys.Core.LanguageModel.CompileEventHandler.Invoke(Object sender, CompileEventArgs e)
ved _3S.CoDeSys.LanguageModelManager.LanguageModelManagerConsolidated.OnBeforeCompile(CompileEventArgs e)
ved _3S.CoDeSys.LanguageModelManager.LanguageModelManagerConsolidated.RaiseAndCheckBeforeCompile(Guid guidApplication, IMessageCategory cmc)
ved _3S.CoDeSys.LanguageModelManager.Compiler35110.Compiler.
(_IPreCompileContext , Guid , Boolean , Boolean , Boolean , Boolean& , _ICompileContext& , _ICompileContext& , IProgressCallback , Boolean , Boolean )
ved _3S.CoDeSys.LanguageModelManager.Compiler35110.Compiler.
(Guid , Boolean , Boolean , Boolean , IOnlineChangeDetails& , IMessage[]& , IMessage[]& )
                Build complete -- 1 errors, 0 warnings : no download possible!

Does strong typing the enums solve your problem ?

see Codesys online help, chapter explicit basic data type

dFx hat geschrieben:
Does strong typing the enums solve your problem ?

No, what i meant was: The variable which was declared as an enum, inside the struct, is changed to an INT.
That is why i strongly suspect the library defined ENUM to be the cause of compile error, when it's part of a library defined STRUCT used in a network variable list.
Maybe a code example will be more clear:

In "CustomLibrary"

//Library ENUM
{attribute 'qualified_only'}
{attribute 'strict'}
TYPE LibraryError :
(
   NO_ERROR := 0,
   ERROR_1,
   ERROR_2  //etc..
);
END_TYPE

//Library STRUCT
TYPE CommonData : 
STRUCT
   eError   :LibraryError; // ENUM
   iDummy   :INT;   
   xDummy   :BOOL;
END_STRUCT
END_TYPE

In Codesys Project with library installed

VAR_GLOBAL //Global Variable list, setup as Network variable list UDP , MainTask, Cyclic Transmission
stCommonData:CustomLibrary.CommonData;
END_VAR

Not able to compile because of Library Enum inside the struct.

I was asking if typing your enum solves your problem, not what your problem is.

exemple :

TYPE COLOR :
(
    white := 16#FFFFFF00,
    yellow := 16#FFFFFF00,
    green := 16#FF00FF00,
    blue := 16#FF0000FF,
    black := 16#88000000
) DWORD := black; // Basic data type is DWORD, default initialization for all COLOR variables is black
END_TYPE

using this explicit type declaration in your library may help to compile your project.

dFx hat geschrieben:
I was asking if typing your enum solves your problem, not what your problem is.
using this explicit type declaration in your library may help to compile your project.

Okay, i misunderstood.

I've just tested your suggestion, but it doesn't solve the compile error in the network variable list.
I should mention i get the "The object reference is not set to an instance of an object." dialog too.

The compile error was caused by the library "Project Information" setup.
Changing the "LanguageModelAttribute" property from the default value "qualified-access-only" to "qualified-access-mandatory" solved the compile error, when declaring library structs with enums, in Network variable list NVL.

Deleting the property gives the same result.