RWTPtrHashMapIterator< K, T, H, EQ, A > Class Template Reference
[STL Extension-based Collections]

Provides an iterator for RWTPtrHashMap. More...

#include <rw/tphdict.h>

List of all members.

Public Member Functions
	RWTPtrHashMapIterator (RWTPtrHashMap< K, T, H, EQ, A > &h)
bool	operator++ ()
K *	operator() ()
RWTPtrHashMap< K, T, H, EQ,A > *	container () const
K *	key () const
void	reset ()
void	reset (RWTPtrHashMap< K, T, H, EQ, A > &m)
T *	value () const

---

Detailed Description

template<class K, class T, class H, class EQ, class A = std:: allocator < K* >>
class RWTPtrHashMapIterator< K, T, H, EQ, A >

RWTPtrHashMapIterator provides an iterator interface to the C++ Standard Library-based collection represented by RWTPtrHashMap. (An STL iterator interface is provided through RWTPtrHashMap::iterator.)

Iteration over an RWTPtrHashMap is pseudo-random and dependent on the capacity of the underlying hash table and the hash function being used.

The current item referenced by this iterator is undefined after construction or after a call to reset(). The iterator becomes valid after being advanced with either a pre-increment or operator()().

For both operator++() and operator()(), iterating past the last element returns a value equivalent to boolean false. Continued increments return a value equivalent to false until reset() is called.

The value type must have operator==() defined. This requirement is imposed by the C++ Standard Library.

Synopsis

 #include<rw/tphdict.h>
 RWTPtrHashMap<K,T,H,EQ,A>m;
 RWTPtrHashMapIterator<K,T,H,EQ,A>itr(m);

Persistence

None

Examples

 #include <rw/tphdict.h>
 #include <iostream>
 #include <rw/cstring.h>
 
 int main() {
    RWTPtrHashMap
      <RWCString,int,RWTHasher<RWCString>,std::equal_to<RWCString> >
        age(RWCString::hash);
 
    RWTPtrHashMapIterator
      <RWCString,int,RWTHasher<RWCString>,std::equal_to<RWCString> >
        itr(age);
 
    age.insert(new RWCString("John"),new int(30));
    age.insert(new RWCString("Steve"),new int(17));
    age.insert(new RWCString("Mark"),new int(24));
 
    for(;++itr;) {
      std::cout << *itr.key()
                << "\'s age is "
                << *itr.value()
                << std::endl;
    }
 
    age.clearAndDestroy();
    return 0;
 }

Program Output (not necessarily in this order):

 John's age is 30
 Mark's age is 24
 Steve's age is 17

---

Constructor & Destructor Documentation

template<class K, class T, class H, class EQ, class A = std:: allocator < K* >>

RWTPtrHashMapIterator< K, T, H, EQ, A >::RWTPtrHashMapIterator

(

RWTPtrHashMap< K, T, H, EQ, A > &

h

)

[inline]

Creates an iterator for the hashmap h. The iterator begins in an undefined state and must be advanced before the first element is accessible.

---

Member Function Documentation

template<class K, class T, class H, class EQ, class A = std:: allocator < K* >>

RWTPtrHashMap<K,T,H,EQ ,A >* RWTPtrHashMapIterator< K, T, H, EQ, A >::container

(

)

const [inline]

Returns a pointer to the collection being iterated over.

template<class K, class T, class H, class EQ, class A = std:: allocator < K* >>

K* RWTPtrHashMapIterator< K, T, H, EQ, A >::key

(

)

const [inline]

Returns the key portion of the association pointed to by self. The return value is undefined if self is not referencing an association within the map.

template<class K, class T, class H, class EQ, class A = std:: allocator < K* >>

K* RWTPtrHashMapIterator< K, T, H, EQ, A >::operator()

(

void

)

[inline]

Advances self to the next element, dereferences the resulting iterator and returns its key. If the iterator has advanced past the last item in the hashmap, returns rwnil.

template<class K, class T, class H, class EQ, class A = std:: allocator < K* >>

bool RWTPtrHashMapIterator< K, T, H, EQ, A >::operator++

(

)

[inline]

Advances self to the next element. If the iterator has been reset or just created, self references the first element. If used when self references the last association in the hashmap, self references an undefined value and the method returns a value equivalent to false. Otherwise, the method returns a value equivalent to true.

Note:

No post-increment operator is provided.

template<class K, class T, class H, class EQ, class A = std:: allocator < K* >>

void RWTPtrHashMapIterator< K, T, H, EQ, A >::reset

(

RWTPtrHashMap< K, T, H, EQ, A > &

m

)

[inline]

Resets the iterator so that after being advanced it will reference the first element of the collection m.

template<class K, class T, class H, class EQ, class A = std:: allocator < K* >>

void RWTPtrHashMapIterator< K, T, H, EQ, A >::reset

(

void

)

[inline]

Resets the iterator so that after being advanced it will reference the first element of the collection.

template<class K, class T, class H, class EQ, class A = std:: allocator < K* >>

T* RWTPtrHashMapIterator< K, T, H, EQ, A >::value

(

void

)

const [inline]

Returns the value portion of the association pointed to by self. The return value is undefined if self is not referencing an association within the map.