A binary fold defined for operator<< will not only do shifts, but can also be used to insert a series of arguments into cout: template > &CirQue>::operator=( CirQue const &rhs) { CirQue tmp(rhs); swap(tmp); } void CirQue>::swap(CirQue &other) { char tmp[sizeof(CirQue)]; memcpy(tmp, &other, sizeof(CirQue)); memcpy(&other, this, sizeof(CirQue)); memcpy(this, tmp, sizeof(CirQue)); } void CirQue>::pop_front() { if (d_size == 0) throw EMPTY; d_front = inc(d_front); –d_size; } void CirQue>::push_back(int const &object) { if (d_size == d_data. 8: Preventing template instantiations In C++ templates are instantiated when the address of a function template or class template object is taken or when a function template or class template is used. HierarchicSort(arr, 2); Then the two elements of the array of pointers to MultiData’s member functions are swapped, and the previous step is repeated: swap(arr[0], arr[1]); sv.

Simple pointers are usually accepted, but if an iterator-object is used it must be able to specify the kind of iterator it represents. Here, the dereference operator is applied to reach the element the reverse iterator refers to. Class template derivation pretty much follows the same rules as ordinary class derivation, not involving class templates. The friend is a template member. In the following example it is initialized for data type std::string: #include “cirque. The derived class type is going to be derived from the base class.

Lvalue transformations are allowed: if a pointer is defined as a non-type parameter, an array name may be specified. The rows member, in turn, uses another ForEach to call its private columns member. Both constructors use a base class initializer to initialize their TableType base class and then call the class’s private member fill to insert data into the TableType base class object. It may call the constructor since the class iterator declared its surrounding class as its friend: template typename PtrVector::iterator PtrVector::begin() { return iterator(*this); } Here is a simple skeleton program, showing how the nested class iterator might be used: int main() { PtrVector vi; vi. Here is its interface: class StringPtr: public std::vector { public: class iterator: public std::iterator { friend class StringPtr; std::vector::iterator d_current; iterator(std::vector::iterator const &current); public: iterator &operator–(); iterator operator–(int); iterator &operator++(); iterator operator++(int); bool operator==(iterator const &other) const; bool operator.

The top level class to the left (VehicleBase) lays the foundation of static polymorphism, by defining that part of the interface that uses the statically redefinable functions. // derive from base classes { public: // specify base class objects // to its constructor using // perfect forwarding Combi(BaseClasses &&. The Bidirectional dereference operator should allow assignment to the data its dereference operator refers to and it should allow stepping backward. Like default function arguments, once a default value is used all remaining template parameters must also use their default values. This is a clear indication that our class could very well be defined as a class template. In this case the template parameters of the template specifying the friend declaration determine (bind) the values of the template parameters of the friend class or function.

token consideration

Here are its essential characteristics: It is an ordinary class, designed to operate as Table’s base class. Therefore, the ForwardIterator dereference operator should be declared as follows: Type &operator*(); Except for the standard operators there are no further requirements for ForwardIterators. FillDirection is an enum, defined by TableType, having values HORIZONTAL and VERTICAL. The sum of all elements of a matrix can of course be computed as the sum of the elements of one of its marginals. In the following sections the available std::iterator class is used to construct an inner class representing a random access iterator.

The top level class to the left (VehicleBase) lays the foundation of static polymorphism, by defining that part of the interface that uses the statically redefinable functions. The Bidirectional dereference operator should allow assignment to the data its dereference operator refers to and it should allow stepping backward. This is a clear indication that our class could very well be defined as a class template. In this case the template parameters of the template specifying the friend declaration determine (bind) the values of the template parameters of the friend class or function.

If such a Matrix is actually required, yet another specialized template must be designed. Rend()); copy(sp. Begin(), &*–rit, Process()); to process all the lines up to the first of the set of trailing empty lines. Here is an example showing how an argument to a function can be forwarded from a template to a function that is itself passed to the template as a pointer to an (unspecified) function: template void caller(Fun fun, ArgType &&arg) { fun(std::forward(arg)); } A function display(ostream &out) and increment(int &x) may now both be called through caller. In the following class StringPtr, an ordinary class is derived from the std::vector container that uses std::string * as its data type: #ifndef INCLUDED_STRINGPTR_H_ #define INCLUDED_STRINGPTR_H_ #include #include class StringPtr: public std::vector { public: StringPtr(StringPtr const &other); ~StringPtr(); StringPtr &operator=(StringPtr const &other); }; #endif This class needs a destructor: as the object stores string pointers, a destructor is required to destroy the strings once the StringPtr object itself is destroyed.

Token Consideration

To represent these marginals we can construct partial specializations defining the class templates MatrixRow and MatrixColumn objects; and we construct a partial specialization handling 1 x 1 matrices. Therefore, in most cases only two function templates must be instantiated: a constructor and the class’s fill member. Therefore, StringPtr::iterator itself must be derived from the existing class std::iterator. The sum of all elements of a matrix can of course be computed as the sum of the elements of one of its marginals. << args); }; Here is another interesting example: a fold expression for the comma operator: verb( template Class imaginary(Type param) in which case Type clearly is an int, and so a Class object is constructed. Forget about polymorphism for a second: when we have a class Derived: public Base then (because of inheritance) a static_cast can be used to cast a Base * to a Derived object. Zip archive that can be retrieved from https://fbb-git. Vline(size_t colIndex): called just before displaying the element in column colIndex. Since the friend function template itself is a template it may be provided with the required template arguments allowing it to become the declaring class’s friend. }; In this case, the actual value of the template type parameter must be specified when referring to a FillDirection value or to its type. Resize(d_nRows * d_nColumns); // enforce complete table // determine max width per column, // and max column width for (size_t col = 0; col < d_nColumns; col++) { size_t width = 0; for (size_t row = 0; row < d_nRows; row++) { size_t len = stringAt(row, col).4: Extended friend declarations Through extended friend declarations, which are also available for class templates, template type parameters can be declared as friends. If the function call operators (operator()) of such classes define parameters then the types of those parameters may also be abstracted by defining the function call operators themselves as member templates. First we have a look at StringPtr::iterator's characteristics: iterator defines StringPtr as its friend, so iterator's constructor may remain private. For example (assuming iter and nCols are defined as in section 22. Front() << ' ' << cp. H): The class template partial specialization once again starts with a template header.Forget about polymorphism for a second: when we have a class Derived: public Base then (because of inheritance) a static_cast can be used to cast a Base * to a Derived object

token consideration

Here are its essential characteristics: It is an ordinary class, designed to operate as Table’s base class. Therefore, the ForwardIterator dereference operator should be declared as follows: Type &operator*(); Except for the standard operators there are no further requirements for ForwardIterators. FillDirection is an enum, defined by TableType, having values HORIZONTAL and VERTICAL. Here is the program: template class Vector2: public std::vector > { typedef typename Vector2::iterator iterator; template friend Class &ForEach(Iterator begin, Iterator end, Class &object, void (Class::*member)(Data &)); public: void process(); private: void rows(std::vector &row); void columns(Type &str); }; template void Vector2::process() { ForEach, std::vector > (this->begin(), this->end(), *this, &Vector2::rows); } template void Vector2::rows(std::vector &row) { ForEach(row. The sum of all elements of a matrix can of course be computed as the sum of the elements of one of its marginals. In the following sections the available std::iterator class is used to construct an inner class representing a random access iterator.

In this case the template parameters of the template specifying the friend declaration determine (bind) the values of the template parameters of the friend class or function

If such a Matrix is actually required, yet another specialized template must be designed. Rend()); copy(sp. Begin(), &*–rit, Process()); to process all the lines up to the first of the set of trailing empty lines. Here is an example showing how an argument to a function can be forwarded from a template to a function that is itself passed to the template as a pointer to an (unspecified) function: template void caller(Fun fun, ArgType &&arg) { fun(std::forward(arg)); } A function display(ostream &out) and increment(int &x) may now both be called through caller. The same holds true for the Vehicle class template: two implementations, one for the Car type, and one for the Truck type. In the following class StringPtr, an ordinary class is derived from the std::vector container that uses std::string * as its data type: #ifndef INCLUDED_STRINGPTR_H_ #define INCLUDED_STRINGPTR_H_ #include #include class StringPtr: public std::vector { public: StringPtr(StringPtr const &other); ~StringPtr(); StringPtr &operator=(StringPtr const &other); }; #endif This class needs a destructor: as the object stores string pointers, a destructor is required to destroy the strings once the StringPtr object itself is destroyed.

Therefore, in most cases only two function templates must be instantiated: a constructor and the class’s fill member. Therefore, StringPtr::iterator itself must be derived from the existing class std::iterator. The sum of all elements of a matrix can of course be computed as the sum of the elements of one of its marginals. << args); }; Here is another interesting example: a fold expression for the comma operator: verb( template can be used to cast a Base * to a Derived object. Zip archive that can be retrieved from https://fbb-git. Vline(size_t colIndex): called just before displaying the element in column colIndex. Since the friend function template itself is a template it may be provided with the required template arguments allowing it to become the declaring class’s friend. }; In this case, the actual value of the template type parameter must be specified when referring to a FillDirection value or to its type. Resize(d_nRows * d_nColumns); // enforce complete table // determine max width per column, // and max column width for (size_t col = 0; col < d_nColumns; col++) { size_t width = 0; for (size_t row = 0; row < d_nRows; row++) { size_t len = stringAt(row, col).

Token Consideration

token consideration

Like default function arguments, once a default value is used all remaining template parameters must also use their default values. The container class for which a random access iterator must be developed may actually store its data elements in many different ways (e. , sum(1, 2, 3); returns 6. , class Car moves these members to CarBase and Truck moves those members to TruckBase. Size() << ' ' << cp. In that case, we'd better use the following algorithm: First, use rit = find_if(lines. To use a StringPtr::iterator in combination with the sort generic algorithm it must also be a RandomAccessIterator. Within a class PtrVector, a class iterator is defined. Iterators of this type allow for assignment operations, iterating from the first to the last element of the series to which the iterator refers.= end) { std::ostringstream str; str << *it++; d_string. Among those, these two members return table element [row][column] for, respectively, a horizontally filled table and a vertically filled table: inline std::string const &TableType::hIndex(size_t row, size_t col) const { return d_string[row * d_nColumns + col]; } inline std::string const &TableType::vIndex(size_t row, size_t col) const { return d_string[col * d_nRows + row]; } The support class TableSupport is used to display headers, footers, captions and separators. This is called the template member function's point of instantiation. D_current; } bool operator<(iterator const &rhv) const; testing whether the left-hand side iterator points to an element of the series located before the element pointed to by the right-hand side iterator: inline bool StringPtr::iterator::operator<(iterator const &other) const { return d_current < other. Third, as illustrated in the next section, designing static polymorphic classes using multiple levels of inheritance is not a trivial task. The other constructor initializes the pointer to 0 and uses the reference data member to refer to the TableSupport object provided by its parameter.The sum of all elements of a matrix can of course be computed as the sum of the elements of one of its marginalsThe top level class to the left (VehicleBase) lays the foundation of static polymorphism, by defining that part of the interface that uses the statically redefinable functions. // derive from base classes { public: // specify base class objects // to its constructor using // perfect forwarding Combi(BaseClasses &&. The Bidirectional dereference operator should allow assignment to the data its dereference operator refers to and it should allow stepping backward. Like default function arguments, once a default value is used all remaining template parameters must also use their default values. This is a clear indication that our class could very well be defined as a class template. In this case the template parameters of the template specifying the friend declaration determine (bind) the values of the template parameters of the friend class or function.If such a Matrix is actually required, yet another specialized template must be designed. Rend()); copy(sp. Begin(), &*--rit, Process()); to process all the lines up to the first of the set of trailing empty lines. Here is an example showing how an argument to a function can be forwarded from a template to a function that is itself passed to the template as a pointer to an (unspecified) function: template void caller(Fun fun, ArgType &&arg) { fun(std::forward(arg)); } A function display(ostream &out) and increment(int &x) may now both be called through caller. In the following class StringPtr, an ordinary class is derived from the std::vector container that uses std::string * as its data type: #ifndef INCLUDED_STRINGPTR_H_ #define INCLUDED_STRINGPTR_H_ #include #include class StringPtr: public std::vector { public: StringPtr(StringPtr const &other); ~StringPtr(); StringPtr &operator=(StringPtr const &other); }; #endif This class needs a destructor: as the object stores string pointers, a destructor is required to destroy the strings once the StringPtr object itself is destroyed.

To represent these marginals we can construct partial specializations defining the class templates MatrixRow and MatrixColumn objects; and we construct a partial specialization handling 1 x 1 matrices. Therefore, in most cases only two function templates must be instantiated: a constructor and the class’s fill member. Therefore, StringPtr::iterator itself must be derived from the existing class std::iterator. The sum of all elements of a matrix can of course be computed as the sum of the elements of one of its marginals. << args); }; Here is another interesting example: a fold expression for the comma operator: verb( template Class imaginary(Type param) in which case Type clearly is an int, and so a Class object is constructed. Forget about polymorphism for a second: when we have a class Derived: public Base then (because of inheritance) a static_cast can be used to cast a Base * to a Derived object. Zip archive that can be retrieved from https://fbb-git. Vline(size_t colIndex): called just before displaying the element in column colIndex. Since the friend function template itself is a template it may be provided with the required template arguments allowing it to become the declaring class’s friend. }; In this case, the actual value of the template type parameter must be specified when referring to a FillDirection value or to its type. Resize(d_nRows * d_nColumns); // enforce complete table // determine max width per column, // and max column width for (size_t col = 0; col < d_nColumns; col++) { size_t width = 0; for (size_t row = 0; row < d_nRows; row++) { size_t len = stringAt(row, col).4: Extended friend declarations Through extended friend declarations, which are also available for class templates, template type parameters can be declared as friends. If the function call operators (operator()) of such classes define parameters then the types of those parameters may also be abstracted by defining the function call operators themselves as member templates. First we have a look at StringPtr::iterator's characteristics: iterator defines StringPtr as its friend, so iterator's constructor may remain private. For example (assuming iter and nCols are defined as in section 22. Front() << ' ' << cp. H): The class template partial specialization once again starts with a template header.Compare this to Class's second constructor, where Class intObject{12}; allows the compiler to create an imaginary function template Class imaginary(Type param) in which case Type clearly is an int, and so a Class object is constructed. Forget about polymorphism for a second: when we have a class Derived: public Base then (because of inheritance) a static_cast can be used to cast a Base * to a Derived object. Zip archive that can be retrieved from https://fbb-git. Vline(size_t colIndex): called just before displaying the element in column colIndex. Since the friend function template itself is a template it may be provided with the required template arguments allowing it to become the declaring class’s friend. }; In this case, the actual value of the template type parameter must be specified when referring to a FillDirection value or to its type. Resize(d_nRows * d_nColumns); // enforce complete table // determine max width per column, // and max column width for (size_t col = 0; col < d_nColumns; col++) { size_t width = 0; for (size_t row = 0; row < d_nRows; row++) { size_t len = stringAt(row, col).

Information about Token Consideration

4: Extended friend declarations Through extended friend declarations, which are also available for class templates, template type parameters can be declared as friends. If the function call operators (operator()) of such classes define parameters then the types of those parameters may also be abstracted by defining the function call operators themselves as member templates. First we have a look at StringPtr::iterator’s characteristics: iterator defines StringPtr as its friend, so iterator’s constructor may remain private. For example (assuming iter and nCols are defined as in section 22. Front() << ' ' << cp. H): The class template partial specialization once again starts with a template header.

token consideration

The class template SortVector presented below is derived from the existing class template std::vector

If such a Matrix is actually required, yet another specialized template must be designed. Rend()); copy(sp. Begin(), &*–rit, Process()); to process all the lines up to the first of the set of trailing empty lines. Here is an example showing how an argument to a function can be forwarded from a template to a function that is itself passed to the template as a pointer to an (unspecified) function: template void caller(Fun fun, ArgType &&arg) { fun(std::forward(arg)); } A function display(ostream &out) and increment(int &x) may now both be called through caller. The same holds true for the Vehicle class template: two implementations, one for the Car type, and one for the Truck type. In the following class StringPtr, an ordinary class is derived from the std::vector container that uses std::string * as its data type: #ifndef INCLUDED_STRINGPTR_H_ #define INCLUDED_STRINGPTR_H_ #include #include class StringPtr: public std::vector { public: StringPtr(StringPtr const &other); ~StringPtr(); StringPtr &operator=(StringPtr const &other); }; #endif This class needs a destructor: as the object stores string pointers, a destructor is required to destroy the strings once the StringPtr object itself is destroyed.

To represent these marginals we can construct partial specializations defining the class templates MatrixRow and MatrixColumn objects; and we construct a partial specialization handling 1 x 1 matrices. Therefore, in most cases only two function templates must be instantiated: a constructor and the class’s fill member. Therefore, StringPtr::iterator itself must be derived from the existing class std::iterator. The sum of all elements of a matrix can of course be computed as the sum of the elements of one of its marginals. In other situations templates are instantiated when they are being used. For example, although the class map can easily be used in combination with the find_if() generic algorithm (section 19. << args); }; Here is another interesting example: a fold expression for the comma operator: verb( template header file must be included. First, the syntax used with static polymorphism is introduced and illustrated; Next, it is shown how classes that use dynamic polymorphism can be converted to classes that use static polymorphism; Finally it is illustrated how static polymorphism can be used to reduce implementation effort.

4: Extended friend declarations Through extended friend declarations, which are also available for class templates, template type parameters can be declared as friends. D_current; } bool operator. If the function call operators (operator()) of such classes define parameters then the types of those parameters may also be abstracted by defining the function call operators themselves as member templates. First we have a look at StringPtr::iterator’s characteristics: iterator defines StringPtr as its friend, so iterator’s constructor may remain private. For example (assuming iter and nCols are defined as in section 22. Usually the derived class objects that are passed to functions expecting base class references are invariants: at fixed locations in programs fixed class types are used to create objects. Front() << ' ' << cp. H): The class template partial specialization once again starts with a template header. It uses the copy generic algorithm to fill the SortVector object from information appearing at the program's standard input stream.In the context of dynamic polymorphism these overridable members are the base class's virtual members. The unpack operator can also be used to define template classes that are derived from any number of base classes. As the language does not support constructions like void function(std::vector &vector) unless function itself is a template, it is not immediately clear how and why such a friend should be constructed. Std::string *operator->() const is an additionally added operator. Therefore it is difficult to construct a template iterator class which is suitable for a large variety of container classes. A circular queue should offer value semantics as well as a move constructor. Size() << ' ' << copy.4: Extended friend declarations Through extended friend declarations, which are also available for class templates, template type parameters can be declared as friends. D_current; } bool operator. If the function call operators (operator()) of such classes define parameters then the types of those parameters may also be abstracted by defining the function call operators themselves as member templates. First we have a look at StringPtr::iterator's characteristics: iterator defines StringPtr as its friend, so iterator's constructor may remain private. For example (assuming iter and nCols are defined as in section 22. Usually the derived class objects that are passed to functions expecting base class references are invariants: at fixed locations in programs fixed class types are used to create objects. Front() << ' ' << cp. H): The class template partial specialization once again starts with a template header. It uses the copy generic algorithm to fill the SortVector object from information appearing at the program's standard input stream.

token consideration

=(iterator const &other) const; int operator-(iterator const &rhs) const; std::string &operator*() const; bool operator<(iterator const &other) const; iterator operator+(int step) const; iterator operator-(int step) const; iterator &operator+=(int step); // increment over `n' steps iterator &operator-=(int step); // decrement over `n' steps std::string *operator->() const;// access the fields of the // struct an iterator points // to. Member functions aren’t directly called, but are called indirectly via the object’s vpointer and their derived class’s Vtable. How to copy such a container to another container. Like function template specializations class template specializations start with a template header that may or may not have an empty template parameter list. Each of the classes to the left is a base class of a single class to the right: VehicleBase is a base class for Vehicle, TruckBase for Truck. In general, if rit is a reverse_iterator pointing to some element and we need an iterator to point to that element, we may use &*rit to initialize the iterator. All types of vehicles should now be derived from CloningVehicle, which automatically provides them with their own implementation of newCopy. With statically polymorphic classes these two characteristics should completely be separated. , matching a const_iterator class), then the const_iterator’s operator* member should be a member returning a non-modifiable value or object.

The top level class to the left (VehicleBase) lays the foundation of static polymorphism, by defining that part of the interface that uses the statically redefinable functions. Alternatively, the allocation might be part of PtrVector’s tasks, when it stores new elements. // derive from base classes { public: // specify base class objects // to its constructor using // perfect forwarding Combi(BaseClasses &&. The Bidirectional dereference operator should allow assignment to the data its dereference operator refers to and it should allow stepping backward. Like default function arguments, once a default value is used all remaining template parameters must also use their default values. In this case the compiler encounters an implicit declaration: the features of the vector class that are actually used by the above program are not individually declared but they are declared as a group, using the extern template declaration. This is a clear indication that our class could very well be defined as a class template. In this case the template parameters of the template specifying the friend declaration determine (bind) the values of the template parameters of the friend class or function.

The class template SortVector is directly derived from the template class std::vector. If such a Matrix is actually required, yet another specialized template must be designed. Rend()); copy(sp. Begin(), &*–rit, Process()); to process all the lines up to the first of the set of trailing empty lines. Here is an example showing how an argument to a function can be forwarded from a template to a function that is itself passed to the template as a pointer to an (unspecified) function: template void caller(Fun fun, ArgType &&arg) { fun(std::forward(arg)); } A function display(ostream &out) and increment(int &x) may now both be called through caller. The same holds true for the Vehicle class template: two implementations, one for the Car type, and one for the Truck type. Because of this the following class Convert cannot be used with Filter: struct Convert { double operator()(int x); // int-to-double std::string operator()(double x); // double-to-string }; This problem can be tackled successfully by the class template std::result_of. One of the requirements of the data type to which the iterators point is that this data type can be inserted into streams. In the following class StringPtr, an ordinary class is derived from the std::vector container that uses std::string * as its data type: #ifndef INCLUDED_STRINGPTR_H_ #define INCLUDED_STRINGPTR_H_ #include #include class StringPtr: public std::vector { public: StringPtr(StringPtr const &other); ~StringPtr(); StringPtr &operator=(StringPtr const &other); }; #endif This class needs a destructor: as the object stores string pointers, a destructor is required to destroy the strings once the StringPtr object itself is destroyed.

token consideration

Here the inner class declares the outer class as its friend (or the other way around). D_maxWidth = width; } } The public member insert is used by the insertion operator (operator<<) to insert a Table into a stream. This may occur in two situations: the circular queue contains no elements or the information was grabbed from a temporary object by some move operation, setting the temporary's d_data member to zero. Accordingly, the above code is altered into: template Type function(Type t) { typename Type::Ambiguous *ptr; return t + *ptr; } Classes fairly often define subtypes. Although discouraged, we might be able to use pointer data types in specific contexts. This is caused by the fact that generic algorithms perform checks on the types of the iterators they receive. As the language does not support constructions like void function(std::vector &vector) unless function itself is a template, it is not immediately clear how and why such a friend should be constructed. As an example consider reading information from a network socket. Usually we pass an object of the class declaring the friend to such a function.

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= end) { std::ostringstream str; str << *it++; d_string. Among those, these two members return table element [row][column] for, respectively, a horizontally filled table and a vertically filled table: inline std::string const &TableType::hIndex(size_t row, size_t col) const { return d_string[row * d_nColumns + col]; } inline std::string const &TableType::vIndex(size_t row, size_t col) const { return d_string[col * d_nRows + row]; } The support class TableSupport is used to display headers, footers, captions and separators. This is called the template member function's point of instantiation. D_current; } bool operator<(iterator const &rhv) const; testing whether the left-hand side iterator points to an element of the series located before the element pointed to by the right-hand side iterator: inline bool StringPtr::iterator::operator<(iterator const &other) const { return d_current < other. Third, as illustrated in the next section, designing static polymorphic classes using multiple levels of inheritance is not a trivial task. When a class template is used in class derivation, the following situations should be distinguished: An existing class template is used as base class when deriving a ordinary class. The other constructor initializes the pointer to 0 and uses the reference data member to refer to the TableSupport object provided by its parameter.To represent these marginals we can construct partial specializations defining the class templates MatrixRow and MatrixColumn objects; and we construct a partial specialization handling 1 x 1 matrices. Therefore, in most cases only two function templates must be instantiated: a constructor and the class's fill member. Therefore, StringPtr::iterator itself must be derived from the existing class std::iterator. The sum of all elements of a matrix can of course be computed as the sum of the elements of one of its marginals. In other situations templates are instantiated when they are being used. For example, although the class map can easily be used in combination with the find_if() generic algorithm (section 19. << args); }; Here is another interesting example: a fold expression for the comma operator: verb( template header file must be included. First, the syntax used with static polymorphism is introduced and illustrated; Next, it is shown how classes that use dynamic polymorphism can be converted to classes that use static polymorphism; Finally it is illustrated how static polymorphism can be used to reduce implementation effort.

4: Extended friend declarations Through extended friend declarations, which are also available for class templates, template type parameters can be declared as friends. D_current; } bool operator. If the function call operators (operator()) of such classes define parameters then the types of those parameters may also be abstracted by defining the function call operators themselves as member templates. First we have a look at StringPtr::iterator’s characteristics: iterator defines StringPtr as its friend, so iterator’s constructor may remain private. For example (assuming iter and nCols are defined as in section 22. Usually the derived class objects that are passed to functions expecting base class references are invariants: at fixed locations in programs fixed class types are used to create objects. Front() << ' ' << cp. H): The class template partial specialization once again starts with a template header. It uses the copy generic algorithm to fill the SortVector object from information appearing at the program's standard input stream.The unpack operator can also be used to define template classes that are derived from any number of base classes. As the language does not support constructions like void function(std::vector &vector) unless function itself is a template, it is not immediately clear how and why such a friend should be constructed. Std::string *operator->() const is an additionally added operator. Therefore it is difficult to construct a template iterator class which is suitable for a large variety of container classes. A circular queue should offer value semantics as well as a move constructor. Size() << ' ' << copy.