How to conditionally change class inheritance at compile-time in Delphi??

I'm working on a Delphi project where I have a specific set of classes defined, such as:

TClassA = class(TObject)
...
TClassB = class(TObject)
...
TMyClass = class(TClassA)
...

I have a requirement where, based on certain conditions that are determined at compile time, I want TMyClass to instead inherit from TClassB.

Essentially, I would like to be able to write something like this:

{$IFDEF SOME_COMPILE_TIME_CONDITION}
TMyClass = class(TClassB)
{$ELSE}
TMyClass = class(TClassA)
{$ENDIF}

Is it possible in Delphi to conditionally define the parent class of TMyClass at compile time? If so, how can I achieve this? If not, are there any workarounds or alternative approaches you can suggest?

I'm not sure if this qualifies for more elegant, but you might have difficulties to find anything else anyway:

{$IFDEF SOME_COMPILE_TIME_CONDITION}
TMyParentClass = TClassB
{$ELSE}
TMyParentClass = TClassA
{$ENDIF}

TMyClass = class(TMyParentClass)

This might be a little off, depending on what you're trying to do, but based on the information I have I'd solve this problem using an interface.

pseudocode...

type
  TMyClass = class( TMyBaseClass ); 
    
  TMyBaseClass = class
  private
    fImplementation: IMyImplementation;
  public
    constructor Create;
  end;
    
constructor TMyBaseClass.Create;
begin
  {$ifdef CONDA}
  fImplementation := TCondAImplementation.Create;
  {$else}
  fImplementation := TCondBImplementation.Create;
  {$end}
end;

Your descendant can then either call protected methods of the base class which call on the differing implementations, OR provide protected access to the fImplementation member directly.