1 // A global event.
2 class DestroyEvent : public Signal::Event {};
3
4 class Employee
5 { ...
6 // Employee-specific events.
7
8 class EnterEvent : public Signal::Event {...};
9 class LeaveEvent : public Signal::Event {...};
10
11 void enter()
12 { ...
13 // Report an employee-entering-facility event.
14 Signal::emit(*this, EnterEvent());
15 }
16
17 void leave()
18 { ...
19 // Report an employee-leaving-facility event.
20 Signal::emit(*this, LeaveEvent());
21 }
22
23 ~Employee()
24 { ...
25 // Report an event of employee being fired.
26 Signal::emit(*this, DestroyEvent());
27 }
28 };
29
30 class PayrollOffice
31 { ...
32 // Callbacks.
33 void employee_enters(
34 const Employee::EnterEvent&, Employee&);
35 void employee_leaves(
36 const Employee::LeaveEvent&, Employee&);
37 };
38
39 PayrollOffice::employee_enters(
40 const Employee::EnterEvent& ev, Employee* employee)
41 {
42 if (ev.is_late()) // Employee is late in.
43 {
44 remember_the_guy(employee);
45 }
46 else { ... }
47 }
48
49 PayrollOffice::employee_leaves(
50 const Employee::LeaveEvent& ev, Employee* employee)
51 {
52 if (ev.is_early()) // Employee is early out.
53 {
54 remember_the_guy(employee);
55 }
56 else { ... }
57 }
58
59 int main()
60 {
61 PayrollOffice po;
62 Employee john;
63
64 typedef PayrollOffice PO;
65
66 Signal::connect(john, po, &PO::employee_enters);
67 Signal::connect(john, po, &PO::employee_leaves);
68
69 // Registered for Employee::EnterEvent callbacks will be
70 // invoked in response to the employee entering facility.
71
72 john.enter();
73
74 Signal::disconnect(john, po, &PO::employee_enters);
75 Signal::disconnect(john, po, &PO::employee_leaves);
76 }
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