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// Copyright (c) 2018-2025 Jean-Louis Leroy
// Distributed under the Boost Software License, Version 1.0.
// See accompanying file LICENSE_1_0.txt
// or copy at http://www.boost.org/LICENSE_1_0.txt)
#include <boost/openmethod.hpp>
#include <boost/openmethod/initialize.hpp>
using boost::openmethod::virtual_ptr;
struct Role {
virtual ~Role() {
}
};
struct Employee : Role {
virtual auto pay() -> double;
};
struct Manager : Employee {
virtual auto pay() -> double;
};
struct Founder : Role {};
struct Expense {
virtual ~Expense() {
}
};
struct Public : Expense {};
struct Bus : Public {};
struct Metro : Public {};
struct Taxi : Expense {};
struct PrivateJet : Expense {};
BOOST_OPENMETHOD_CLASSES(
Role, Employee, Manager, Founder, Expense, Public, Bus, Metro, Taxi,
PrivateJet);
BOOST_OPENMETHOD(pay, (virtual_ptr<Employee>), double);
BOOST_OPENMETHOD(
approve, (virtual_ptr<const Role>, virtual_ptr<const Expense>, double),
bool);
BOOST_OPENMETHOD_OVERRIDE(pay, (virtual_ptr<Employee>), double) {
return 3000;
}
BOOST_OPENMETHOD_OVERRIDE(pay, (virtual_ptr<Manager> exec), double) {
return next(exec) + 2000;
}
BOOST_OPENMETHOD_OVERRIDE(
approve, (virtual_ptr<const Role>, virtual_ptr<const Expense>, double),
bool) {
return false;
}
BOOST_OPENMETHOD_OVERRIDE(
approve, (virtual_ptr<const Employee>, virtual_ptr<const Public>, double),
bool) {
return true;
}
BOOST_OPENMETHOD_OVERRIDE(
approve, (virtual_ptr<const Manager>, virtual_ptr<const Taxi>, double),
bool) {
return true;
}
BOOST_OPENMETHOD_OVERRIDE(
approve, (virtual_ptr<const Founder>, virtual_ptr<const Expense>, double),
bool) {
return true;
}
auto main() -> int {
boost::openmethod::initialize();
}
auto call_pay(Employee& emp) -> double {
return pay(emp);
}
auto Employee::pay() -> double {
return 3000;
}
auto Manager::pay() -> double {
return Employee::pay() + 2000;
}
auto call_pay_vfunc(Employee& emp) -> double {
return emp.pay();
}
auto call_approve(const Role& r, const Expense& e, double a) -> bool {
return approve(r, e, a);
}
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