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////////////////////////////////////////////////////////////////////////////////
// The Loki Library
// Copyright (c) 2006 Peter Kmmel
// Permission to use, copy, modify, distribute and sell this software for any
// purpose is hereby granted without fee, provided that the above copyright
// notice appear in all copies and that both that copyright notice and this
// permission notice appear in supporting documentation.
// The author makes no representations about the
// suitability of this software for any purpose. It is provided "as is"
// without express or implied warranty.
////////////////////////////////////////////////////////////////////////////////
// $Header: /cvsroot/loki-lib/loki/test/ScopeGuard/main.cpp,v 1.8 2006/02/20 23:40:09 rich_sposato Exp $
#include <loki/ScopeGuard.h>
#include <vector>
#include <string>
#include <iostream>
void Decrement(int& x)
{
--x;
}
struct UserDatabase
{
void AddFriend(const std::string&, const std::string&)
{
throw 55;
}
};
class User
{
public:
User(UserDatabase* db) : fCount(0), pDB_(db)
{}
std::string GetName();
void AddFriend(User& newFriend);
void AddFriendGuarded(User& newFriend);
size_t countFriends();
int fCount;
private:
typedef std::vector<User*> UserCont;
UserCont friends_;
UserDatabase* pDB_;
};
std::string User::GetName()
{
return "A name";
}
size_t User::countFriends()
{
return friends_.size();
}
void User::AddFriend(User& newFriend)
{
friends_.push_back(&newFriend);
fCount++;
pDB_->AddFriend(GetName(), newFriend.GetName());
}
void User::AddFriendGuarded(User& newFriend)
{
friends_.push_back(&newFriend);
Loki::ScopeGuard guard = Loki::MakeObjGuard(friends_, &UserCont::pop_back);
fCount++;
Loki::ScopeGuard guardRef = Loki::MakeGuard(Decrement, Loki::ByRef(fCount));
pDB_->AddFriend(GetName(), newFriend.GetName());
guard.Dismiss();
guardRef.Dismiss();
}
int main()
{
UserDatabase db;
User u1(&db);
User u2(&db);
try{ u1.AddFriend(u2); }
catch (...){}
std::cout << "u1 countFriends: " << u1.countFriends() << "\n";
std::cout << "u1 fCount : " << u1.fCount << "\n";
try{ u2.AddFriendGuarded(u1); }
catch (...){}
std::cout << "u2 countFriends: " << u2.countFriends() << "\n";
std::cout << "u2 fCount : " << u2.fCount << "\n";
#if defined(__BORLANDC__) || defined(_MSC_VER)
system("PAUSE");
#endif
}
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