RWTFunctorMapR2< SR, Key, S1 > Class Template Reference
[Functor Map]

A functor map that takes two arguments at invocation time, and returns a value. More...

#include <rw/functor/map/RWTFunctorMapR2.h>

Inheritance diagram for RWTFunctorMapR2< SR, Key, S1 >:

Public Types
typedef Key	key_type
typedef unsigned(*	hash_function )(const Key &)
Public Member Functions
	RWTFunctorMapR2 (hash_function hf, size_t size=RW_FUNCTOR_MAP_CAPACITY)
	RWTFunctorMapR2 (const RWTFunctorMapR2< SR, Key, S1 > &second)
	~RWTFunctorMapR2 (void)
RWTFunctorMapR2< SR, Key, S1 > &	operator= (const RWTFunctorMapR2< SR, Key, S1 > &second)
SR	operator() (Key key, S1 s1) const
RWTFunctorMapR2Imp< SR, Key, S1 > &	body (void) const
bool	add (Key key, RWTFunctorR1< SR, S1 > functor)
bool	remove (Key key)
bool	contains (Key key) const
bool	find (Key key, RWTFunctorR1< SR, S1 > &functor) const
void	resize (size_t size)
void	clear (void)
size_t	entries (void) const
void	setDefault (RWTFunctorR1< SR, S1 > functor)
RWTFunctorR1< SR, S1 >	getDefault (void) const

Detailed Description

template<class SR, class Key, class S1>
class RWTFunctorMapR2< SR, Key, S1 >

The RWTFunctorMapR2 class represents the functor maps that take two arguments at invocation time, and return a value. Since one of these arguments is the key into the map, the functors that are held in the map take only one argument; they are RWTFunctorR1 functors.

Functor maps allow functors to be grouped together in a key/value table structure. They add functors to the map with a corresponding key of type key_type, later using it to invoke the desired functor.

Examples

 #include <rw/cstring.h>
 #include <rw/rwdate.h>
 #include <rw/functor/functorR1.h>
 #include <rw/functor/map/RWTFunctorMapR2.h>
 
 // Functions that we want to wrap in functors:
 class BankAccount{
    float getBalance(RWDate date){ return 1234.56; }
    float getInterest(RWDate date){ return 61.51; }
 };
 
 int main () {
 
   BankAccount currentAcct;
 
   // Create new RWTFunctorR1s to be the values in the map.
   RWTFunctorR1<float,RWDate> balanceFunctor = rwtMakeFunctorR1(
      (float(*)(RWDate))0, currentAcct, &BankAccount::getBalance);
   RWTFunctorR1<float,RWDate> interestFunctor = rwtMakeFunctorR1(
      (float(*)(RWDate))0, currentAcct, &BankAccount::getInterest);
 
   // Create keys with which to associate the values.
   RWCString balanceKey = "balance";
   RWCString interestKey = "interest";
 
   // Declare a new map. A complete, but empty instance now exists.
   RWTFunctorMapR2<float,RWCString,RWDate> fmap(RWCString::hash);
 
   // Add something to the map to make it useful.
   fmap.add(balanceKey, balanceFunctor);
   fmap.add(interestKey, interestFunctor);
 
   // Create an RWDate to represent the date for which we want info.
   RWDate today;
 
   // Invoking the map with the key "balance" results in the
   // balanceFunctor being called.
   float balance = fmap("balance", today);
 
   // Invoking the map with the key "interest" results in the
   // interestFunctor being called.
   float interest = fmap("interest", today);
 
   cout << "Account balance as of " << today << " is "
        << balance << endl;
   cout << "Interest earned as of " << today << " is "
        << interest << endl;
 
   return 0;
 }

Program output:

 Account balance as of 07/14/99 is 1234.56
 Interest earned as of 07/14/99 is 61.51