#include <rw/tpsrtdli.h> RWTPtrSortedDlist<T,C> srtdlist;
RWTPtrSortedDlist requires the Standard C++ Library.
This class maintains an always-sorted pointer-based collection of values, implemented as a doubly-linked list. Items are ordered according to a comparison object of type C. Class T is the type pointed to by the items in the collection. C must induce a total ordering on elements of type T via a public member
bool operator()(const T& x, const T& y)
which returns true if x should precede y within the collection. The structure less<T> from the C++-standard header file <functional> is an example. Note that items in the collection will be dereferenced before being compared.
The value type must have operator== and operator< defined. This requirement is imposed by the Standard C++ Library.
Isomorphic.
In this example, a sorted doubly-linked list of RWDates is exercised.
//
// tpsrtdli.cpp
//
#include <rw/tpsrtdli.h>
#include <rw/rwdate.h>
#include <iostream.h>
main(){
RWTPtrSortedDList<RWDate,greater<RWDate> > lst;
lst.insert(new RWDate(10, "Aug", 1991));
lst.insert(new RWDate(9, "Aug", 1991));
lst.insert(new RWDate(1, "Sep", 1991));
lst.insert(new RWDate(14, "May", 1990));
lst.insert(new RWDate(1, "Sep", 1991)); // Add a duplicate
lst.insert(new RWDate(2, "June", 1991));
for (int i=0; i<lst.entries(); i++)
cout << *lst[i] << endl;
lst.clearAndDestroy();
return 0;
}
Program Output:
09/01/91
09/01/91
08/10/91
08/09/91
06/02/91
05/14/90
Class RWTPtrSortedVector<T> is an alternative always-sorted pointer-based collection. RWTPtrDlist<T> is an unsorted pointer-based doubly-linked list.
Class list<T*,allocator> is the C++-standard collection that serves as the underlying implementation for this class.
typedef rw_deref_compare<C,T> container_comp; typedef list<T*,allocator> container_type; typedef container_type::size_type size_type; typedef container_type::difference_type difference_type; typedef container_type::const_iterator const_iterator; typedef container_type::iterator iterator; typedef T* value_type; typedef T*& reference; typedef T* const& const_reference;
RWTPtrSortedDlist<T,C>();
Constructs an empty doubly-linked list.
RWTPtrSortedDlist<T,C>(const RWTPtrSortedDlist<T,C>& lst);
Copy constructor.
RWTPtrSortedDlist<T,C>(const list<T*,allocator>& lst);
Constructs a doubly-linked list by iterating over all elements in lst and performing an order preserving insertion on self for each.
RWTPtrSortedDlist<T,C>(size_type n, T* p);
Constructs a doubly-linked list with n elements, each initialized to p.
RWTPtrSortedDlist<T,C>(T** first,T** last);
Constructs a doubly-linked list by copying and sorting elements from the array of T*s pointed to by first, up to, but not including, the element pointed to by last.
bool operator<(const RWTPtrSortedDlist<T,C>& lst) const;
Returns true if self compares lexicographically less than lst, otherwise returns false. Items in each collection are dereferenced before being compared.
bool operator==(const RWTPtrSortedDlist<T,C>& lst) const;
Returns true if self compares equal to lst, otherwise returns false. Two collections are equal if both have the same number of entries, and iterating through both collections produces, in turn, individual elements that compare equal to each other. Elements are dereferenced before being compared.
reference operator()(size_type i); const_reference operator()(size_type I) const;
Returns a reference to the ith element of self. Index i should be between 0 and one less then the number of entries, otherwise the results are undefined--no bounds checking is performed.
reference operator[](size_type I); const_reference operator[](size_type I) const;
Returns a reference to the ith element of self. Index i must be between 0 and one less then the number of entries in self, otherwise the function throws an exception of type RWBoundsErr.
void apply(void (*fn)(T*&,void*), void* d); void apply(void (*fn)(T*,void*), void* d); void apply(void (*fn)(const T*,void*), void* d) const;
Applies the user-defined function pointed to by fn to every item in the collection. This function must have one of the prototypes:
void yourfun(const T* a, void* d); void yourfun(T* a, void* d); void yourfun(T* &a,void* d)
Client data may be passed through parameter d.
reference at(size_type i); const_reference at(size_type i) const;
Returns a reference to the ith element of self. Index i must be between 0 and one less then the number of entries in self, otherwise the function throws an exception of type RWBoundsErr.
iterator begin(); const_iterator begin() const;
Returns an iterator positioned at the first element of self.
void clear();
Clears the collection by removing all items from self.
void clearAndDestroy();
Removes all items from the collection and uses operator delete to destroy the objects pointed to by those items. Do not use this method if multiple pointers to the same object are stored.
bool contains(const T* a) const;
Returns true if there exists an element t in self such that the expression(*t == *a) is true, otherwise returns false.
bool contains(bool (*fn)(const T*,void*), void* d) const;
Returns true if there exists an element t in self such that the expression ((*fn)(t,d)) is true, otherwise returns false. fn points to a user-defined tester function which must have prototype:
bool yourTester(const T* a, void* d);
Client data may be passed through parameter d.
iterator end(); const_iterator end() const;
Returns an iterator positioned "just past" the last element in self.
size_type entries() const;
Returns the number of items in self.
const T* find(const T* a) const;
If there exists an element t in self such that the expression (*t == *a) is true, returns t. Otherwise, returns rwnil.
const T* find(bool (*fn)(const T*,void*), void* d) const;
If there exists an element t in self such that the expression ((*fn)(t,d)) is true, returns t. Otherwise, returns rwnil. fn points to a user-defined tester function which must have prototype:
bool yourTester(const T* a, void* d);
Client data may be passed through parameter d.
reference first(); const_reference first() const;
Returns a reference to the first element of self.
size_type index(const T* a) const;
Returns the position of the first item t in self such that (*t == *a), or returns the static member npos if no such item exists.
size_type index(bool (*fn)(const T*,void*), void* d) const;
Returns the position of the first item t in self such that((*fn)(t,d)) is true, or returns the static member npos if no such item exists. fn points to a user-defined tester function which must have prototype:
bool yourTester(const T* a, void* d);
Client data may be passed through parameter d.
size_type insert(const list<T*,allocator>& a);
Adds the items from a to self in an order preserving way. Returns the number of items inserted.
bool insert(T* a);
Adds the item a to self. The collection remains sorted. Returns true.
bool isEmpty() const;
Returns true if there are no items in the collection, false otherwise.
bool isSorted() const;
Returns true if the collection is sorted relative to the supplied comparator object, false otherwise.
T*& last(); T* const& last() const;
Returns a reference to the last item in the collection.
size_type merge(const RWTPtrSortedDlist<T,C>& dl);
Inserts all elements of dl into self, preserving sorted order. Returns the number of items inserted.
size_type occurrencesOf(const T* a) const;
Returns the number of elements t in self such that the expression (*t == *a) is true.
size_type occurrencesOf(bool (*fn)(const T*,void*), void* d) const;
Returns the number of elements t in self such that the expression((*fn)(t,d)) is true. fn points to a user-defined tester function which must have prototype:
bool yourTester(const T* a, void* d);
Client data may be passed through parameter d.
T* remove(const T* a);
Removes and returns the first element t in self such that the expression (*t == *a) is true. Returns rwnil if there is no such element.
T* remove(bool (*fn)(const T*,void*), void* d);
Removes and returns the first element t in self such that the expression ((*fn)(t,d)) is true. Returns rwnil if there is no such element. fn points to a user-defined tester function which must have prototype:
bool yourTester(const T* a, void* d);
Client data may be passed through parameter d.
size_type removeAll(const T* a);
Removes all elements t in self such that the expression (*t == *a) is true. Returns the number of items removed.
size_type removeAll(bool (*fn)(const T*,void*), void* d);
Removes all elements t in self such that the expression ((*fn)(t,d))is true. Returns the number of items removed. fn points to a user-defined tester function which must have prototype:
bool yourTester(const T* a, void* d);
Client data may be passed through parameter d.
T* removeAt(size_type i);
Removes and returns the item at position i in self. This position must be between zero and one less then the number of entries in the collection, otherwise the function throws an exception of type RWBoundsErr.
T* removeFirst();
Removes and returns the first item in the collection.
T* removeLast();
Removes and returns the first item in the collection.
const list<T*,allocator>& std() const;
Returns a reference to the underlying C++-standard collection that serves as the implementation for self.
const size_type npos;
This is the value returned by member functions such as index to indicate a non-position. The value is equal to ~(size_type)0.
RWvostream&
operator<<(RWvostream& strm,
const RWTPtrSortedDlist<T,C>& coll);
RWFile&
operator<<(RWFile& strm, const RWTPtrSortedDlist<T,C>& coll);
Saves the collection coll onto the output stream strm, or a reference to it if it has already been saved.
RWvistream& operator>>(RWvistream& strm, RWTPtrSortedDlist<T,C>& coll); RWFile& operator>>(RWFile& strm, RWTPtrSortedDlist<T,C>& coll);
Restores the contents of the collection coll from the input stream strm.
RWvistream& operator>>(RWvistream& strm, RWTPtrSortedDlist<T,C>*& p); RWFile& operator>>(RWFile& strm, RWTPtrSortedDlist<T,C>*& p);
Looks at the next object on the input stream strm and either creates a new collection off the heap and sets p to point to it, or sets p to point to a previously read instance. If a collection is created off the heap, then you are responsible for deleting it.