hashtree.ipp

/******************************************************************************
 * MODULE     : hashtree
 * DESCRIPTION: A tree class that stores a node's children in a hashmap instead
 *              of a list. Can be used to implement a dictionary that maps
 *              strings to strings efficiently.
 * COPYRIGHT  : (C) 2002  Felix Breuer
 *******************************************************************************
 * This software falls under the GNU general public license version 3 or later.
 * It comes WITHOUT ANY WARRANTY WHATSOEVER. For details, see the file LICENSE
 * in the root directory or <http://www.gnu.org/licenses/gpl-3.0.html>.
 ******************************************************************************/

#ifndef HASHTREE_C
#define HASHTREE_C
#include "hashtree.hpp"

template <class K, class V>
inline bool
hashtree_rep<K, V>::contains (K key) {
  return children->contains (key);
}

template <class K, class V>
void
hashtree_rep<K, V>::add_child (K key, hashtree<K, V>& child) {
  child.realize (); // make sure the child has a rep!
  children (key)= child;
}

template <class K, class V>
void
hashtree_rep<K, V>::add_new_child (K key) {
  hashtree<K, V> child;
  add_child (key, child);
}

template <class K, class V>
void
hashtree_rep<K, V>::set_label (V val) {
  label= val;
}

template <class K, class V>
V
hashtree_rep<K, V>::get_label () {
  return label;
}

/******************************************************************************
 * Method to ensure that hashtree is non null
 ******************************************************************************/

template <class K, class V>
inline void
hashtree<K, V>::realize () {
  if (this->is_nil ()) {
    *this= hashtree ();
  }
}

/******************************************************************************
 * Overloaded operators
 ******************************************************************************/

template <class K, class V>
inline hashtree_rep<K, V>*
hashtree<K, V>::operator->(void) {
  // always make sure there is a rep!
  realize ();
  return this->rep;
}

template <class K, class V>
inline hashtree<K, V>
hashtree<K, V>::operator[] (K key) {
  if (*this->contains (key)) return *this->children (key);
  else TM_FAILED ("read-access to non-existent node requested");
}

template <class K, class V>
inline hashtree<K, V>
hashtree<K, V>::operator() (K key) {
  realize ();
  if (!(*this)->contains (key)) (*this)->add_new_child (key);
  return (*this)->children (key);
}

/******************************************************************************
 * Functions
 ******************************************************************************/

template <class K, class V>
inline bool
is_nil (hashtree<K, V> ht) {
  return ht.is_nil ();
}

template <class K, class V>
inline int
N (hashtree<K, V> ht) {
  return N (ht->children);
}

#endif // HASHTREE_C