/*
 * Copyright (C) 2002 Daniel Heck
 *
 * 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 2
 * 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, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 */
#ifndef ECL_ALIST_HH
#define ECL_ALIST_HH

/* 
 * This file defines STL-like associative lists (similar to the ones
 * found in Lisp dialects, but with a C++-ish look and feel.  They can
 * be used as a std::map replacement when linear searches aren't
 * expensive.
 */

#include <string>
#include <list>
#include <utility>

namespace ecl
{
    template <class KEY, class VAL> 
    class AssocList : public std::list<std::pair<KEY, VAL> > {
    public:
        typedef KEY key_type;
        typedef std::pair<KEY,VAL> value_type;
        typedef typename std::list<value_type>::iterator iterator;
        typedef typename std::list<value_type>::const_iterator const_iterator;

        //	
        // Lookup of keys
        //
        iterator find (const key_type &key) {
            iterator i=this->begin(), e=this->end();
            for (; i!=e; ++i) 
                if (i->first == key)
                    break;
            return i;
        }

        const_iterator find (const key_type &key) const {
            const_iterator i=this->begin(), e=this->end();
            for (; i!=e; ++i) 
                if (i->first == key)
                    break;
            return i;
        }

        VAL &operator[] (const key_type &key) { 
            iterator i=find(key);
            if (i==this->end())
                i=insert(this->end(), make_pair(key, VAL()));
            return i->second;
        }
        
        void remove_key(const key_type &key) {
            iterator i = find(key);
            if (i != this->end())
                erase(i);
        }
    };
}
#endif

