RWTValMap(3C++)

RWTValMap<K,T,C> - Rogue Wave library class

As shipped in IRIX 6.5.5. Unchanged since IRIX 6.5.

Name
     RWTValMap<K,T,C> - Rogue Wave library class

Synopsis
              #include <rw/tvmap.h>
          RWTValMap<K,T,C> m;



Standard C++ Library Dependent!



     RWTValMap requires the Standard C++ Library.


Description
     This class maintains a collection of keys, each with an associated item
     of type T.  Order is determined by the key according to a comparison
     object of type C.  C must induce a total ordering on elements of type K
     via a public member
        bool operator()(const K& x, const K& y) const which returns true if x
     and its partner should precede y and its partner within the collection.
     The structure less<T> from the C++-standard header file <functional> is
     an example.  RWTValMap<K,T,C> will not accept a key that compares equal
     to any key already in the collection.  (RWTValMultiMap<K,T,C> may contain
     multiple keys that compare equal to each other.)  Equality is based on
     the comparison object and not on the == operator.  Given a comparison
     object comp, keys a and b are equal if
        !comp(a,b) && !comp(b,a).

Persistence
     Isomorphic.

Examples
     In this example, a map of RWCStrings and RWDates is exercised.

              //



              // tvmbday.cpp
          //
          #include <rw/tvmap.h>
          #include <rw/cstring.h>
          #include <rw/rwdate.h>
          #include <iostream.h>
          main(){
            RWTValMap<RWCString, RWDate, less<RWCString> > birthdays;
            birthdays.insert("John", RWDate(12, "April",1975));
            birthdays.insert("Ivan", RWDate(2, "Nov", 1980));
            // Alternative syntax:
            birthdays["Susan"] = RWDate(30, "June", 1955);
            birthdays["Gene"] = RWDate(5, "Jan", 1981);
            // Print a birthday:
            cout << birthdays["John"] << endl;
            return 0;
          }
          Program Output:

Related Classes
     04/12/75


     Class RWTValMultiMap<K,T,C> offers the same interface to a collection
     that accepts multiple keys that compare equal to each other.
     RWTValSet<T,C> maintains a collection of keys without the associated
     values.  Class map<K,T,C,allocator> is the C++-standard collection that
     serves as the underlying implementation for this collection.

Public Typedefs
              typedef map<K,T,C,allocator>                   container_type;
          typedef container_type::iterator               iterator;
          typedef container_type::const_iterator         const_iterator;
          typedef container_type::size_type              size_type;
          typedef pair <const K,T>                       value_type;
          typedef pair <const K,T>&                      reference;
          typedef const pair <const K,T>&                const_reference;



Public Constructors
              RWTValMap<K,T,C>(const C& comp = C());


     Constructs an empty map with comparator comp.

              RWTValMap<K,T,C>(const container_type& m);


     Constructs a map by copying all elements of m.

              RWTValMap<K,T,C>(const RWTValMap<K,T,C>& rwm);


     Copy constructor.

              RWTValMap<K,T,C>(const value_type* first,
               const value_type* last,const C& comp = C());


     Constructs a map by copying elements from the array of value_type pairs
     pointed to by first, up to, but not including, the pair pointed to by

     last.

Public Member Operators
              RWTValMap<K,T,C>&
          operator=(const RWTValMap<K,T,C>& m);
          RWTValMap<K,T,C>&
          operator=(const container_type& m);


     Destroys all elements of self and replaces them by copying all
     associations from m.

              bool
          operator<(const RWTValMap<K,T,C>& m) const;
          bool
          operator<(const container_type & m) const;


     Returns true if self compares lexicographically less than m, otherwise
     returns false.  Assumes that type K has well-defined less-than semantics
     (T::operator<(const K&) or equivalent).

              bool
          operator==(const RWTValMap<K,T,C>& m) const;
          bool
          operator==(const container_type & m) const;


     Returns true if self compares equal to m, otherwise returns false.  Two
     collections are equal if both have the same number of entries, and
     iterating through both collections produces, in turn, individual pairs
     that compare equal to each other.

              T&
          operator[](const K& key);


     Looks up key and returns a reference to its associated item.  If the key
     is not in the dictionary, then it will be added with an associated item
     provided by the default constructor for type T.

Public Member Functions
              void
          apply(void (*fn)(const K&, T&, void*),void* d);
          void
          apply(void (*fn)(const K&, const T&, void*), void* d) const;


     Applies the user-defined function pointed to by fn to every association
     in the collection.  This function must have one of the prototypes:  void
     yourfun(const K& key, T& a, void* d);
      void yourfun(const K& key, const T& a,void* d); Client data may be
     passed through parameter d.

              void
          applyToKeyAndValue(void (*fn)(const K&, T&, void*),void* d);
          void
          applyToKeyAndValue
          (void (*fn)(const K&, const T&, void*), void* d) const;


     This is a deprecated version of the apply member above.  It behaves
     exactly the same as apply.

              iterator
          begin();
          const_iterator
          begin() const;


     Returns an iterator positioned at the first pair in self.

              void
          clear();


     Clears the collection by removing all items from self.  Each key and its
     associated item will have its destructor called.

              bool
          contains(const K& key) const;


     Returns true if there exists a key j in self that compares equal to key,
     otherwise returns false.

              bool
          contains(bool (*fn)(const_reference,void*), void* d) const;


     Returns true if there exists an association a in self such that the
     expression ((*fn)(a,d)) is true, otherwise returns false.  fn points to a
     user-defined tester function which must have prototype:





                 bool yourTester(const_reference 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 association in self.

              size_type
          entries() const;


     Returns the number of associations in self.

              bool
          find(const K& key, Key& r) const;


     If there exists a key j in self that compares equal to key, assigns j to
     r and returns true.  Otherwise, returns false and leaves the value of r
     unchanged.

              bool
          find(bool (*fn)(const_reference,void*), void* d,
               pair<K,T>& r) const;


     If there exists an association a in self such that the expression
     ((*fn)(a,d)) is true, assigns a to r and returns true.  Otherwise,
     returns false and leaves the value of k unchanged.  fn points to a user-
     defined tester function which must have prototype:





                 bool yourTester(const_reference a, void* d);


     Client data may be passed through parameter d.

              bool
          findValue(const K& key, T& r) const;


     If there exists a key j in self that compares equal to key, assigns the
     item associated with j to r and returns true.  Otherwise, returns false
     and leaves the value of r unchanged.

              bool
          findKeyValue(const K& key, K& kr, T& tr) const;

     If there exists a key j in self that compares equal to key, assigns j to
     kr, assigns the item associated with j to tr, and returns true.
     Otherwise, returns false and leaves the values of kr and tr unchanged.

              bool
          insert(const K& key, const T& a);


     Adds key with associated item a to the collection.  Returns true if the
     insertion is successful, otherwise returns false.  The function will
     return true unless the collection already holds an association with the
     equivalent key.

              bool
          insertKeyAndValue(const K& key, const T& a);


     This is a deprecated version of the insert member above.  It behaves
     exactly the same as insert.

              bool
          isEmpty() const;


     Returns true if there are no items in the collection, false otherwise.

              size_type
          occurrencesOf(const K& key) const;


     Returns the number of keys j in self that compare equal to key.

              size_type
          occurrencesOf
          (bool (*fn)(const_reference&,void*),void* d) const;


     Returns the number of associations a in self such that the
     expression((*fn)(a,d)) is true.  fn points to a user-defined tester
     function which must have prototype:





                 bool yourTester(const_reference& a, void* d);


     Client data may be passed through parameter d.

              bool
          remove(const K& key);


     Removes the first association with key j in self such that j compares
     equal to key and returns true.  Returns false if there is no such
     association.

              bool
          remove(bool (*fn)(const_reference,void*), void* d);


     Removes the first association a in self such that the expression
     ((*fn)(a,d)) is true and returns true.  Returns false if there is no such
     element.  fn points to a user-defined tester function which must have
     prototype:





                 bool yourTester(const_reference a, void* d);


     Client data may be passed through parameter d.

              size_type
          removeAll(const K& key);


     Removes all associations with key j in self such that j compares equal to
     key.  Returns the number of items removed.

              size_type
          removeAll(bool (*fn)(const_reference,void*), void* d);


     Removes all associations a in self such that the expression
     ((*fn)(a,d))is true.  Returns the number of items removed.  fn points to
     a user-defined tester function which must have prototype:





                 bool yourTester(const_reference a, void* d);


     Client data may be passed through parameter d.

              map<K,T,C,allocator>&
          std();
          const map<K,T,C,allocator>&
          std() const;


     Returns a reference to the underlying C++-standard collection that serves
     as the implementation for self.  This reference may be used freely,
     providing access to the C++-standard interface as well as
     interoperability with other software components that make use of the
     C++-standard collections.

Related Global Operators
              RWvostream&
          operator<<(RWvostream& strm, const RWTValMap<K,T,C>& coll);
          RWFile&
          operator<<(RWFile& strm, const RWTValMap<K,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, RWTValMap<K,T,C>& coll);
          RWFile&
          operator>>(RWFile& strm, RWTValMap<K,T,C>& coll);


     Restores the contents of the collection coll from the input stream strm.

              RWvistream&
          operator>>(RWvistream& strm, RWTValMap<K,T,C>*& p);
          RWFile&
          operator>>(RWFile& strm, RWTValMap<K,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.