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#ifndef DB_HPP
#define DB_HPP
// db.hpp - convenience wrappers over std::map<K, V>
//
// Copyright © 2013 Ben Longbons <b.r.longbons@gmail.com>
//
// This file is part of The Mana World (Athena server)
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
# include "sanity.hpp"
# include <map>
template<class K, class V>
class Map
{
typedef std::map<K, V> Impl;
Impl impl;
public:
typedef typename Impl::iterator iterator;
typedef typename Impl::const_iterator const_iterator;
iterator begin() { return impl.begin(); }
iterator end() { return impl.end(); }
const_iterator begin() const { return impl.begin(); }
const_iterator end() const { return impl.end(); }
V *search(const K& k)
{
iterator it = impl.find(k);
if (it == impl.end())
return nullptr;
return &it->second;
}
const V *search(const K& k) const
{
const_iterator it = impl.find(k);
if (it == impl.end())
return nullptr;
return &it->second;
}
void insert(K k, V v)
{
// As far as I can tell, this is the simplest way to
// implement move-only insert-with-replacement.
iterator it = impl.lower_bound(k);
// invariant: if it is valid, it->first >= k
if (it != impl.end() && it->first == k)
it->second = std::move(v);
else
it = impl.insert(std::pair<K, V>(std::move(k), std::move(v))).first;
return (void)&it->second;
}
V *init(K k)
{
return &impl[k];
}
void erase(const K& k)
{
impl.erase(k);
}
void clear()
{
impl.clear();
}
bool empty()
{
return impl.empty();
}
};
template<class K, class V>
class DMap
{
typedef Map<K, V> Impl;
Impl impl;
public:
typedef typename Impl::iterator iterator;
typedef typename Impl::const_iterator const_iterator;
iterator begin() { return impl.begin(); }
iterator end() { return impl.end(); }
const_iterator begin() const { return impl.begin(); }
const_iterator end() const { return impl.end(); }
V get(K k)
{
V *vp = impl.search(k);
return vp ? *vp : V();
}
void put(K k, V v)
{
if (v == V())
impl.erase(k);
else
impl.insert(k, v);
}
void clear()
{
impl.clear();
}
};
#endif // DB_HPP
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