A cool thing about a Go map or a dictionary, is that if a key is not initialized, then it returns the default value.
Here's an example:
intmap := make(map[int]bool)
Suppose now you add an entry into intmap with:
intmap[1] = true
And you retrieve a non-existent key:
boolval := intmap[2]
boolval will then contain a value of false, the default value for a boolean in Go.
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