RWFunctor0RWHandleBase
#include <rw/functor/functor0.h>
RWFunctor0 represents the group of functors that are invoked without any arguments and whose invocation returns no value.
A function object, or a functor, is an object that encapsulates a call to an associated global or member function. When a functor is invoked, it calls the associated function.
Instances of class RWFunctor0 act as handles to functor implementations or bodies. Such implementations are created by using either the rwtMakeFunctor0() global functions or macros. Each of these methods creates a new body instance, and returns the handle to that instance. See the example below.
Note that although an instance of this class is invoked with no arguments, and returns no value, the encapsulated function may have both arguments and a return value.
The arguments that will be passed to the encapsulated function are provided to the functor at the time of creation. They are stored within the functor object, and are retrieved at the time of invocation.
Any return value of the function will be ignored by the functor, and hence not passed back to the user. If you are interested in the function's return value, see the RWTFunctorR0 group of classes.
#include <iostream.h>
#include <rw/functor/functor0.h>
// A function to be encapsulated in a functor.
void print(){ cout << "Hello World" << endl; }
int main () {
// Create a handle ('functor'), and
// assign a new body to it.
RWFunctor0 functor = rwtMakeFunctor0((void)(*)())0, print);
// Invoking the functor will print "Hello World."
functor();
return 0;
}
OUTPUT:
Hello World
typedef void (*CallerSignature)(void);
The signature of the functor invocation.
RWFunctor0(void);
Constructs an empty, invalid, handle instance. To create a viable handle, use the rwtMakeFunctor0() global functions or macros.
RWFunctor0(RWStaticCtor);
Constructs a global static handle instance. The constructor will not reset any values that may have been set in invocations prior to the constructor call.
RWFunctor0(const RWFunctor0& second);
Copy constructor. Binds a new handle instance to the functor body instance, if any, associated with the second handle instance.
RWFunctor0& operator=(const RWFunctor0& second);
Assignment operator. Detaches this handle instance from any functor body instance it currently references, and binds it to the functor body instance, if any, associated with the second handle instance.
void operator()(void) const;
Invokes the functor, calling the encapsulated function. Throws an RWTHRInvalidPointer exception if the handle has no associated body.
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