Undo

The procedure Undo undoes any changes to the global variables that resulted from the previous function call. It has no effect on other variables that the user may have defined using objects stored in the global variables.

Restart;
GlobalObserverDeclarations

$\left\{\right\}$

DeclareObservers[A,B];
GlobalObserverDeclarations

$\left\{A\to \left\{\right\},B\to \left\{\right\}\right\}$

Undo;
GlobalObserverDeclarations

$''Last\; change\; to\; global\; variables\; has\; been\; undone!''$
$\left\{\right\}$

Restart