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我编写了一个自定义记录器，并希望添加 POU 的名称pszComponent以便于调试。
我编写了一个自定义FB_init，它接受 POU 的名称作为字符串作为输入，但遇到了令人费解的行为（至少对我而言）。

有人可以向我解释为什么以下编译

VAR
  name : STRING := __POUNAME();
  test : FB_logAdd(sCmpName:=name);
END_VAR

但以下

VAR
  test : FB_logAdd(sCmpName:=__POUNAME());
END_VAR

引发以下编译器错误？

[ERROR]         Internal error:System.NullReferenceException: Object reference not set to an instance of an object.    at _3S.CoDeSys.LanguageModelManager.CompileContext.NeedsExternalFunctionCall(IOperatorExpression op, ICompiledType type, String& stFunctionName, TypeClass& tcWithType)    at _3S.CoDeSys.Compiler35160.ExpressionTypifier.(_IOperatorExpression )    at _3S.CoDeSys.LanguageModelManager.OperatorExpression.Accept(IExprementVisitor visitor)    at _3S.CoDeSys.Compiler35160.InterfaceCompiler.(_IVariable , _ISignature , ISignature , ISignature , IScope5 , _ICompileContext , IList`1 , IVariable[] , ExpressionTypifier , TypeChecker , ErrorVisitor )    at _3S.CoDeSys.Compiler35160.InterfaceCompiler.(IList`1& , IVariable[] , _IVariable , IScope5 , _ICompileContext , _ISignature , ISignature , ISignature , ExpressionTypifier , TypeChecker , ErrorVisitor )    at _3S.CoDeSys.Compiler35160.InterfaceCompiler.(_IVariable , IScope5 , _ICompileContext , _ISignature , ISignature , ISignature , ExpressionTypifier , TypeChecker , ErrorVisitor )    at _3S.CoDeSys.Compiler35160.InterfaceCompiler.(_IVariable , IScope5 , _ICompileContext , _ISignature , ExpressionTypifier , TypeChecker , ErrorVisitor , ISignature , ISignature )    at _3S.CoDeSys.Compiler35160.InterfaceCompiler.(_IVariable , IScope5 , _ICompileContext , _ISignature )    at _3S.CoDeSys.Compiler35160.InterfaceCompiler.(_ISignature , IScope5 , _ICompileContext )    at _3S.CoDeSys.Compiler35160.Compiler.(_ICompileContext , _IPreCompileContext , _IPreCompileContext , _ICompileContext , Boolean , Boolean , Boolean& , IProgressCallback )    at _3S.CoDeSys.Compiler35160.Compiler.(_ICompileContext , Boolean , Boolean , _IPreCompileContext , _IPreCompileContext , _ICompileContext , Boolean , Boolean& , IProgressCallback )    at _3S.CoDeSys.Compiler35160.Compiler.(Guid , Boolean , Boolean , Boolean , Boolean& , _ICompileContext& , _ICompileContext& , IProgressCallback , Boolean , Boolean , Boolean )

是因为它__POUNAME()的行为像一个功能块而不是我假设的功能吗？
这就是为什么

VAR
  test : FB_logAdd(pCmpName:=ADR(__POUNAME()));
END_VAR

如果我将输入更改为字符串指针也可以吗？

编辑 1

我最初的FB_init样子是这样的

//FB_Init is always available implicitly and it is used primarily for initialization.
//The return value is not evaluated. For a specific influence, you can also declare the
//methods explicitly and provide additional code there with the standard initialization
//code. You can evaluate the return value.
METHOD FB_Init: BOOL
VAR_INPUT
    bInitRetains: BOOL; // TRUE: the retain variables are initialized (reset warm / reset cold)
    bInCopyCode: BOOL;  // TRUE: the instance will be copied to the copy code afterward (online change)   
    sCmpName : STRING;
END_VAR

THIS^.sCmpName := sCmpName;

因为我想用FB_logAdd(sCmpName:=__POUNAME())（仍然抛出上述错误）初始化功能块

如果我使用FB_logAdd(sCmpName:=THIS^.___POUNAME())，它会引发编译器错误

C0004:  '__POUNAME' is no component of 'THIS^'

这是有道理的，因为__POUNAME()它是一个运算符，实际上并不属于父功能块（我认为）

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