RWTFunctor2<S1,S2>

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RWTFunctor2<S1,S2>

Module: Threads Package: Functor


RWTFunctor2<S1,S2>   RWHandleBase

Local Index
Header File
Description
Example
Public Typedefs
Public Constructors
Public Destructor
Public Member Operators
Protected Member Function
See Also

Local Index

Members

body()
CallerSignature

operator()()
operator=()

RWTFunctor2()
S1Type

S2Type
~RWTFunctor2()

Header File

#include <rw/functor/functor2.h>

Description

RWTFunctor2<S1,S2> represents the group of functors that are invoked with two 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 RWTFunctor2 act as handles to functor implementations or bodies. Such implementations are created by using either the rwtMakeFunctor2() 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 two arguments, and returns no value, the encapsulated function may have more arguments and a return value.

The additional 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 that the function may have will be ignored by the functor, and hence not passed back to the user. (If you are interested in the function's return value, you should probably be using the RWTFunctorR1 group of classes.)

Example

#include <iostream.h>
#include <rw/functor/functor2.h>

void foo(int x, short y){ 
   cout << "x is " << x << ", y is " << y << endl;  
}

int main () {
   // Create a handle and assign a new body to it. 
   RWTFunctor2<int,short> functor = rwtMakeFunctor2( (void(*)(int,short))0, foo );

   // Invoke the functor with two caller arguments. 
   functor(42,3);
   return 0;
}

Output:
   x is 42, y is 3

Public Typedefs

typedef S1 S1Type;

The type of the first caller argument.

typedef S2 S2Type;

The type of the second caller argument.

typedef void (*CallerSignature)(S1,S2);

The signature of the functor invocation.

Public Constructors

RWTFunctor2();

Constructs an empty, invalid, handle instance. To create a viable handle, use the rwtMakeFunctor1() global function or macros.

RWTFunctor2(RWStaticCtor);

Constructs a global static handle instance. Constructor will not reset any values that may have been set in invocations prior to the constructor call.

RWTFunctor2(const RWTFunctor2<S1,S2>& second);

Copy constructor. Binds a new handle instance to the functor body instance, if any, associated with the second handle instance.

RWTFunctor2(RWTFunctor2Imp<S1,S2>* functorImp);

Body constructor. Constructs a new RWTFunctor2 handle from an existing body.

Public Destructor

~RWTFunctor2();

Destructor.

Public Member Operators

RWTFunctor2<S1, S2>& 
operator=(const RWTFunctor2<S1,S2>& 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()(S1 s1, S2 s2) const;

Invokes the functor, calling the encapsulated function. Throws an RWTHRInvalidPointer if the handle has no associated body.

Protected Member Function

RWTFunctor2Imp<S1,S2>&
body() const;

Gets a reference for the body instance, if any; otherwise, throws an RWTHRInvalidPointer exception.