CopperSpice API  1.7.2
QHash< Key, Val, Hash, KeyEqual >::const_iterator Class Reference

STL style const iterator for QHash. More...

Public Methods

 const_iterator () = default
 
 const_iterator (iterator other)
 
const Key & key () const
 
bool operator!= (const_iterator other) const
 
const Val & operator* () const
 
const_iterator operator+ (size_type n) const
 
const_iterator & operator++ ()
 
const_iterator operator++ (int)
 
const_iterator & operator+= (size_type n)
 
const_iterator operator- (size_type n) const
 
const_iterator & operator-= (size_type n)
 
const Val * operator-> () const
 
bool operator== (const_iterator other) const
 
const std::pair< const Key, Val > & pair () const
 
const Val & value () const
 

Friends

bool operator!= (iterator iter1, const_iterator iter2)
 
bool operator== (iterator iter1, const_iterator iter2)
 
class QHash< Key, Val, Hash, KeyEqual >
 

Detailed Description

template<typename Key, typename Val, typename Hash, typename KeyEqual>
class QHash< Key, Val, Hash, KeyEqual >::const_iterator

The QHash::const_iterator class provides an STL style const iterator for QHash. QHash features both STL style iterators and Java style iterators.

QHash::const_iterator allows you to iterate over a QHash. If you want to modify the QHash as you iterate over it use QHash::iterator instead.

After construction you must initialize the iterator using a method like QHash::constBegin(), QHash::constEnd(), or QHash::find() before you can start iterating. The following is an example which prints all of the (key, value) pairs in the container.

hash.insert("January", 1);
hash.insert("February", 2);
...
hash.insert("December", 12);
for (auto iter = map.constBegin(); iter != map.constEnd(); ++iter) {
cout << iter.key() << ": " << iter.value() << endl;
}

Unlike QMap which orders its items by key, QHash stores its items in an arbitrary order.

See also
QHash::iterator

Constructor & Destructor Documentation

template<typename Key , typename Val , typename Hash , typename KeyEqual >
QHash< Key, Val, Hash, KeyEqual >::const_iterator::const_iterator ( )
default

Constructs an uninitialized iterator.

Methods like key(), value(), and operator++() must not be called on an uninitialized iterator. Use operator=() to assign a value to it before using it.

See also
QHash::constBegin(), QHash::constEnd()
template<typename Key , typename Val , typename Hash , typename KeyEqual >
QHash< Key, Val, Hash, KeyEqual >::const_iterator::const_iterator ( iterator  other)
inline

Constructs a copy of other.

Method Documentation

template<typename Key , typename Val , typename Hash , typename KeyEqual >
const Key & QHash< Key, Val, Hash, KeyEqual >::const_iterator::key ( ) const
inline

Returns the current item's key.

See also
value()
template<typename Key , typename Val , typename Hash , typename KeyEqual >
bool QHash< Key, Val, Hash, KeyEqual >::const_iterator::operator!= ( const_iterator  other) const
inline

Returns true if other points to a different item than this iterator, otherwise it returns false.

See also
operator==()
template<typename Key , typename Val , typename Hash , typename KeyEqual >
const Val & QHash< Key, Val, Hash, KeyEqual >::const_iterator::operator* ( ) const
inline

Returns the current item's value. Equivalent to calling value().

See also
key()
template<typename Key , typename Val , typename Hash , typename KeyEqual >
const_iterator QHash< Key, Val, Hash, KeyEqual >::const_iterator::operator+ ( size_type  n) const
inline

Returns an iterator to the item at n positions forward from this iterator. If n is negative, the iterator goes backward.

This operation can be slow for large values of n.

See also
operator-()
template<typename Key , typename Val , typename Hash , typename KeyEqual >
const_iterator & QHash< Key, Val, Hash, KeyEqual >::const_iterator::operator++ ( )
inline

The prefix ++ operator (++i) advances the iterator to the next item in the hash and returns an iterator to the new current item.

Calling this method on QHash::end() leads to undefined behavior.

template<typename Key , typename Val , typename Hash , typename KeyEqual >
const_iterator QHash< Key, Val, Hash, KeyEqual >::const_iterator::operator++ ( int  )
inline

The postfix ++ operator (i++) advances the iterator to the next item in the hash and returns an iterator to the previously current item.

template<typename Key , typename Val , typename Hash , typename KeyEqual >
const_iterator & QHash< Key, Val, Hash, KeyEqual >::const_iterator::operator+= ( size_type  n)
inline

Advances the iterator by n items. If n is negative the iterator goes backward.

This operation can be slow for large values of n.

See also
operator-=(), operator+()
template<typename Key , typename Val , typename Hash , typename KeyEqual >
const_iterator QHash< Key, Val, Hash, KeyEqual >::const_iterator::operator- ( size_type  n) const
inline

Returns an iterator to the item at n positions backward from this iterator. If n is negative the iterator goes forward.

This operation can be slow for large values of n.

See also
operator+()
template<typename Key , typename Val , typename Hash , typename KeyEqual >
const_iterator & QHash< Key, Val, Hash, KeyEqual >::const_iterator::operator-= ( size_type  n)
inline

Makes the iterator go back by n items. If n is negative the iterator goes forward.

This operation can be slow for large values of n.

See also
operator+=(), operator-()
template<typename Key , typename Val , typename Hash , typename KeyEqual >
const Val * QHash< Key, Val, Hash, KeyEqual >::const_iterator::operator-> ( ) const
inline

Returns a pointer to the current item's value.

See also
value()
template<typename Key , typename Val , typename Hash , typename KeyEqual >
bool QHash< Key, Val, Hash, KeyEqual >::const_iterator::operator== ( const_iterator  other) const
inline

Returns true if other points to the same item as this iterator, otherwise it returns false.

See also
operator!=()
template<typename Key , typename Val , typename Hash , typename KeyEqual >
const std::pair< const Key, Val > & QHash< Key, Val, Hash, KeyEqual >::const_iterator::pair ( ) const
inline

Returns the current item's key and value as a pair.

template<typename Key , typename Val , typename Hash , typename KeyEqual >
const Val & QHash< Key, Val, Hash, KeyEqual >::const_iterator::value ( ) const
inline

Returns the current item's value.

See also
key(), operator*()

Friends And Related Function Documentation

template<typename Key , typename Val , typename Hash , typename KeyEqual >
bool operator!= ( iterator  iter1,
const_iterator  iter2 
)
friend

Returns true if iter1 points to a different item than iter2, otherwise it returns false.

template<typename Key , typename Val , typename Hash , typename KeyEqual >
bool operator== ( iterator  iter1,
const_iterator  iter2 
)
friend

Returns true if iter1 points to the same item as iter2, otherwise it returns false.