STL map utilities

map_utils.hpp

/*
 * map_utils.hpp
 * Utilities for accessing STL maps
 * original work by: Gydo194
 */

#ifndef MAP_GET_H
#define MAP_GET_H

#include <map>

using namespace std;

template<class K, class V>
bool map_get(map<K,V> *src_map, K *key_source, V *dest_var) {
    try
    {
        *dest_var = src_map->at(*key_source);
        return true;
    }
    catch(out_of_range oor)
    {
        return false;
    }
}

/*
 * copies a value from the map into the variable pointed to, leaves the mem. loc and pointer
 * untouched when the key is not in the map
 */
template<class K, class V>
bool map_get(map<K,V> *src_map, const K key_source, V *dest_var) {
    try
    {
        *dest_var = src_map->at(key_source);
        return true;
    }
    catch(out_of_range oor)
    {
        return false;
    }
}

/*
 * allocates an new NULL value on the specified key in the map
 */
template<class K, class V>
bool map_allocate_empty(map<K,V> *dest_map, const K key)
{
	V empty_val;
	pair<K,V> ins = pair<K,V>(key,empty_val);
	dest_map->insert(ins);
	return true;
}

template<class K, class V>
bool map_contains(map<K,V> *src_map, const K key)
{
	return 1 == src_map->count(key);
}

/*
 * updates a value in the map.
 */
template<class K, class V>
bool map_set(map<K,V> *dest_map, const K key, V *value)
{
	try
	{
		dest_map->at(key) = *value;
		return true;
	}
	catch(out_of_range oor)
	{
		return false;
	}
}

/*
 * inserts a new value into the map
 */
template<class K, class V>
bool map_insert(map<K,V> *dest_map, K key, V value)
{
	return dest_map->insert(pair<K,V>(key,value)).second;
}





/*
 * map_access returns a reference to the value from the map.
 * the benefit of this is the ability to actually set the value from the result of this function.
 * this function should be avoided in its current state, as it will return an invalid reference
 * in case of an out_of_range.
 */
template<class K, class V>
V& map_access(map<K,V> *src_map, const K *key)
{
	try
	{
		return src_map->at(*key);
	}
	catch(out_of_range oor)
	{
		//cout << "map_access caught OOR\n";
		//map_allocate_empty<K,V>(src_map,
	}
}




#endif //MAP_GET_H