Źródła:
base_basket.hpp:
#ifndef BASE_BASKET_HPP
#define BASE_BASKET_HPP
#include
#include
template
class Basket {
protected:
_Cl *storage;
_T_prio *priorities;
unsigned int size;
virtual bool isgreater(unsigned int &i, unsigned int &j) const =0;
public:
Basket();
Basket(const unsigned int &_size);
Basket(const Basket &basket);
virtual ~Basket();
Basket& operator=(const Basket &basket);
unsigned int getsize() const;
/* _CL add(_CL &addthis);
void remove(unsigned int i);
bool remove(_CL &smthglikethat);
bool isin(_CL &smthglikethat);*/
};
template
Basket<_Cl, _T_prio>::Basket() {
storage = NULL;
priorities = NULL;
size = 0u;
std::clog << "Basket default constructor" << std::endl;
}
template
Basket<_Cl, _T_prio>::Basket(const unsigned int &_size) {
size = _size;
if(size == 0u) {
storage = NULL;
priorities = NULL;
}
else {
storage = new _Cl[size];
priorities = new _T_prio[size];
}
std::clog << "Basket size constructor" << std::endl;
}
template
Basket<_Cl, _T_prio>::Basket(const Basket &basket) {
size = basket.getsize();
if(size == 0u) {
storage = NULL;
priorities = NULL;
}
else {
for(unsigned int i=0; i
storage[i] = basket.storage[i];
}
for(unsigned int i=0; i
priorities[i] = basket.priorities[i];
}
}
std::clog << "Basket copy constructor" << std::endl;
}
template
Basket<_Cl, _T_prio>::~Basket() {
delete[] storage;
delete[] priorities;
std::clog << "Basket destructor" << std::endl;
}
template
Basket<_Cl, _T_prio>& Basket<_Cl, _T_prio>::operator=(const Basket<_Cl, _T_prio> &basket) {
if(storage != NULL) {
delete[] storage;
}
if(priorities != NULL) {
delete[] priorities;
}
size = basket.getsize();
if(size == 0u) {
storage = NULL;
priorities = NULL;
}
else {
for(unsigned int i=0; i
storage[i] = basket.storage[i];
}
for(unsigned int i=0; i
priorities[i] = basket.priorities[i];
}
}
std::clog << "Basket operator=" << std::endl;
return *this;
}
template
unsigned int Basket<_Cl, _T_prio>::getsize() const {
return size;
}
#endif // BASE_BASKET_HPP
basket.hpp:
#ifndef BASKET_HPP
#define BASKET_HPP
#include "base_basket.hpp"
#include
template
class Priority_Basket : public Basket<_Cl, _T_prio> {
protected:
virtual bool isgreater(unsigned int &i, unsigned int &j) const {
return priorities[i] > priorities[j];
}
public:
Priority_Basket() : Basket<_Cl, _T_prio>() {
std::clog << "Priority_Basket default constructor" << std::endl;
}
Priority_Basket(const unsigned int &size) : Basket<_Cl, _T_prio>(size) {
std::clog << "Priority_Basket size constructor" << std::endl;
}
Priority_Basket(const Priority_Basket &basket) : Basket<_Cl, _T_prio>(basket) {
std::clog << "Priority_Basket copy constructor" << std::endl;
}
};
#endif // BASKET_HPP
main.cpp:
#include "basket.hpp"
int main() {
Priority_Basket a(5u);
Priority_Basket b(a);
return 0;
}
Makefile:
SHELL = /bin/sh
CXX = g++
.SUFFIXES:
.SUFFIXES: .cpp .hpp .o
OBJS = main.o
EXE = main
PEDANT = -ansi -pedantic
WARN = -Wall -Wextra $(PEDANT)
#debug
CXXFLAGS = $(WARN) -c -ggdb
CXXLINK = $(WARN)
#release
#CXXFLAGS = $(WARN) -c -O2 -DNDEBUG
#CXXLINK = $(WARN) -s
all: $(EXE)
$(EXE): $(OBJS)
$(CXX) $(CXXLINK) $(OBJS) -o $(EXE)
main.o: main.cpp basket.hpp
$(CXX) $(CXXFLAGS) main.cpp
.PHONY: clean basket.hpp
clean:
rm -f $(OBJS) $(EXE)
basket.hpp: base_basket.hpp
Kilka słów wyjaśnienia: W pliku base_basket.hpp jest klasa Basket, w której jest wirtualna funkcja isgreater. W pliku basket.hpp jest klasa Priority_Basket, która dziedziczy klasę Basket i implementuje funkcję isgreater. Wewnątrz implementacji isgreater w klasie Priority_Basket odwołuje się do zmiennych protected z klasy Basket. Kompilacja:
etam@etam-laptop:~/koszyk> make
g++ -Wall -Wextra -ansi -pedantic -c -ggdb main.cpp
In file included from main.cpp:6:
basket.hpp: In member function ‘virtual bool Priority_Basket<_Cl, _T_prio>::isgreater(unsigned int&, unsigned int&) const’:
basket.hpp:12: error: ‘priorities’ was not declared in this scope
make: *** [main.o] Błąd 1
Żeby było ciekawiej po usunięciu template wszystko ładnie się kompiluje i działa,
