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Yes, actually it does. The thing on its left is the * token. It might help to visualize this if you add whitespace between the TObject and * tokens - the compiler will simply ignore that whitespace, but the tokens are still treated separate: void FreeAndNil(const TObject * const &Obj); So, the 1st const binds to the TObject type, and the 2nd const binds to the * pointer, so you end up with the Obj parameter being a reference to type "const pointer to const TObject".

in C++, const is much more flexible than in Delphi, more so than that documentation explains. The semantics of const depend on WHERE the const is placed. In general, const applies to the thing on its left, unless there is nothing there then it applies to the thing on its right instead. So, for instance, if we have these declarations in C++: void FreeAndNil(const TObject* &Obj); or void FreeAndNil(TObject const * &Obj); Then the const applies only to the TObject instance that is being pointed at, so its data members cannot be changed by the function. The const does not apply to the TObject* pointer itself, which is being passed by reference, so that pointer can be freely assigned a new value by the function to point at a different TObject instance or null, and that change is reflected to the caller's variable. Whereas if we have this declaration instead in C++: void FreeAndNil(TObject* const &Obj); Then the const applies only to the TObject* pointer itself, thus it can't be assigned a new value by the function. The const does not apply to the TObject instance, so its data members can be freely modified by the function. The two examples above can be combined to have a const pointer to a const TObject instance: void FreeAndNil(const TObject* const &Obj); or void FreeAndNil(TObject const * const &Obj); It does not make sense to put const after Obj, since by definition a reference cannot be reseated once it has been initialized: void FreeAndNil(... &Obj const); or void FreeAndNil(... &Obj const); Now, given this declaration in Delphi: procedure FreeAndNil(const [ref] Obj: TObject); The semantics of this are roughly equivalent to the above C++ code - a reference to a const pointer to a const TObject instance (I don't have 10.4 installed to look at how FreeAndNil() is actually declared in C++Builder). That is fine and good to get a pointer to a TObject-based instance passed into the function by reference, but normally Delphi would then not allow that pointer to be assigned a new value. So FreeAndNil() employs a workaround for that: TObject(Pointer(@Obj)^) := nil; Applying the @ operator to a reference parameter returns the address of the passed variable. Then all const-ness on that variable is being casted away, thus allowing the function to assign a new value to that variable. That would be something along the lines of the following in C++: ((TObject*&)(*(void**)&ref)) = nullptr; or reinterpret_cast<TObject*&>(const_cast<void*&>(*reinterpret_cast<const void * const *>(&ref))) = nullptr; or const_cast<TObject*&>(const_cast<const TObject * const &>(ref)) = nullptr; Except that if a C++ compiler sees a 'const TObject* const &' function parameter, and is passed anything other than a 'const TObject*' variable, an implicit conversion is performed and an rvalue gets passed to the reference parameter, so the function modifies the rvalue, not the caller's original variable. For example: https://ideone.com/CO4Dac So, there is likely some additional compiler magic in C++Builder to avoid this problem with FreeAndNil() specifically. Unless I'm missing something.

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Would choose FreeNullminator, ... hasta la vista .... Object

This code must crash horribly on the first call to FreeAndNil with a non-nil pointer. So this code was either never used or the memory is already freed and the pointer set to nil before that call.

Everyone please vote for Global Generics https://quality.embarcadero.com/browse/RSP-13724 So we can have type safe FreeAndNil without quirks and lies.

Refactoring away from objects to something else and forgetting FreeAndNil is probably the number one source of defects of this category which is why I am happy for this change in 10.4 even though it also has its quirks most notably an API that tells a lie.

Thanks, I am using a portion of mORMot (check my mORMotJWT repository: https://github.com/andrea-magni/mORMot-JWT) I have extracted (with permission) in order to benefit of their JWT implementation (that is way better than the JOSE implementation). Unfortunately, they are (were?) not supporting Linux compilation with Delphi because of ARC. That's the reason I still have JOSE and mORMotJWT support at the same time. Glad you solved! Sincerely, Andrea

This is not the correct process as I understand it, you should: - Fork the repository on github web, so you that have your own repository that you can permission to make changes - Clone your forked repository to your local pc - Change the source code as needed (following the contribution rules, if any) - Commit and push your changes to your forked repository - Make a pull request to the original SynEdit2 repository, and wait for acceptance

Try finslly still wrong. You must acquire the resource immediately before the try Foo := TMyObject.Create; try Foo.Use; finally Foo.Free; end; As you have it, if an exception is raised before the variable is assigned, you'll call Free on an uninitialized variable.