Are you looking for an example in using Delphi 8's class operators?
Well, the source codes in the RTL had some class operators stuff, but there were no class operator demos shipped with the product.
That being said, I investigated into the issue of that, and the following example was written by me. It's probably the world's first Delphi 8 class operators example, outside of Borland.
Initially, I wanted to write something like
Degree = packed record;
Fahrenheit = packed record(IConvertible) class operator Implicit(AValue: Degree): Fahrenheit;end;
Degree = packed record(IConvertible) class operator Implicit(AValue: Fahrenheit): Degree;end;
But then, I discovered I couldn't declare forward records, just as I could declare forward classes, or forward procedures, collectively known as forward declarations.
That being said, the following is a complete example to using class operators. The example demonstrates converting between degree celsius, degree fahrenheit and kelvin.
The example can be downloaded here.
In 2017, with the release of Delphi 10.2 Tokyo, Embarcadero introduced a specialized implementation of the Observer pattern into the System.Classes unit. While it has been in the wild for 9 years, it remains a "hidden" architecture for many, primarily because it serves as the invisible engine behind LiveBindings. Other than live bindings, you can also use the Observer pattern as a way to update component settings to the Windows registry, an .ini file, or persist it elsewhere.
System.Classes