C++

- http://www.natahaus.ru/ , . . ! , . , . . . . . . , , , e-mail - .

CCCC++++++++

......................................................................................................................................... 9 ..................................................................................................................... 9

1. ............................................................................................ 11

1. ++? .................................................................... 13 ++......................................................................................................................................................... 13 ++................................................................................................................................ 15 ................................................................................................................................ 16 ...................................................................................... 17

2. ++ ...................................................................................................................... 19 ........................................................................................................................ 19

const............................................................................................................................................................ 19 ....................................................................................................... 23

.................................................................................................................. 25 .................................................................................................................................... 25 ................................................................................................................................................. 28 ................................................................................................................................................. 29

...................................................................................................................................... 33 .......................................................................................................................................... 33 ............................................................................................................................................ 40 ............................................................................................................................................ 41 ............................................................................................................................ 46

3. ............................................................................ 55 ? ............................................................................................. 55 ................................................................................................................................................... 55 .................................................................................................................................... 56 ........................................................................................ 56

................................................................................................................................ 57 ...................................................................................................................... 57 ................................................................................................................. 57 ................................................................................................... 58 ................................................................................................................................ 58 .................................................................................................. 59 !...................................................................................... 59 ............................................................................................................................................. 59

......................................................................... 59 .............................................................................. 60 ................................................................................ 60 ............................................................................................. 60

4. .......................................................................................................................... 63

4

ANSI ...........................................................................................63 ..................................................................................................63 ..........................................................................................................66 ...............................................................................................................67

...............................................................................................69 .............................................................................................................................69

2. ..................................................................................................71

5. ...............................................................................................................73 ......................................................................................................................................73 .................................................................................................................75 -> .............................................................................................................................................75 ...................................................................................................75 ....................................................................................................................76 .............................................................................................77 ?.....................................................................................................78

.................................................................................................................................................78 NULL ...............................................................................................................78 ...........................................................................................................................80 ..............................................................................................................................................82

6. .....................................................................85 ............................................................................................................85 ......................................................................................................................................86 ............................................................................................................................................87 ...............................................................................................................................................87 .............................................................................................................................................88 ...............................................................................................89

C++.....................................................................................................................................90 ? ...................................................................................................................................90 ....................................................................................................................................90 .................................................................................................................92 /..................................................................................................................92

7. .........................................................................93 .........................................................................................................................93 .......................................................................................................................93 ........................................................................................................94 ............................................................................................................................96

.............................................................................................................................................................96 ....................................................................................97 .................................................................................................................................................98 .........................................................................................................................99 ...................................................................................................102 ......................................................................................................................................103 ...............................................................................................................103 ....................................................................................................................105

.....................................................................................................................................106 ...................................................................................................106 .......................................................107 ................................................107

................................................................................................................................................107 ....................................................................................................................................................108

8. , .......................................................................111 [] ..........................................................................................................................111

5

........................................................................................................... 111 [] ............................................................................................... 112 ........................................................................................................ 112 [] ........................................................................................ 113 [].................................................................................................................... 113

...................................................................................................................................................... 114 ................................................................................................. 114 ......................................................................................................... 115 ->........................................................................................ 116 - ................................................................................................................................ 117

.................................................................................................................................................. 117 ............................................................................................................................ 118 .......................................................................................................................... 118 ? ............................................................................................................................................. 119 , ............................................................................................ 119 ................................................................................................................................... 120 ....................................................................................................... 121

............................................................................................................................. 123 ....................................................................................... 124 ...................................................................................................................... 126 ...................................................................................................... 127 ................................................................................................................................ 129 ..................................................................................................................................................... 131

9. .............................................................. 137 ........................................................................................................................ 137 ............................................................................................................................................... 137 .................................................................................................................................................... 138 ? .................................................................................................................................................. 138

................................................................................................................................. 138 .................................................................................................................. 139 ......................................................................................................................................... 140 ...................................................................................................... 141 ................................................................................................................................. 144 ......................................................................................................................... 145

.............................................................................................................................. 145 ....................................................................................................................... 146 ConstPtr......................................................................................................................................... 147 LockPtr .......................................................................................................................................... 149 ..................................................................................................... 150 ............................................................................................................ 151 .................................................................................................................................................... 152

................................................................................................................................................... 152 .......................................................................................................................... 152 ............................................................................................................ 153 ........................................................................................................................ 154 ............................................................................................................................. 154

................................................................................................................ 155

3. ..................................................................................................................... 157

10. ....................................................................................... 159 ......................................................................................................... 159 ......................................................................................... 160 ...................................................................................................................... 160 ...................................................................................................... 161

..................................................................................................................... 162

6

....................................................................................................................................163 ........................................................................................................164 .........................................................................................................165 ................................................................................................166

...........................................................................................................................................167 11. ............................................169 ..........................................................................................................................169

make- ..........................................................................................................................................170 make- ....................................................................170 .........................................................................170 ......................................................................171 ......................................................................................................................172 : ............................................................172 =!....................................................................................173

......................................................................................................................................173 ..............................................................................................................................174 ...............................................................................175 ............................................................................................................176

..........................................................................................................................................177 12. ................................................................................................179 ..............................................................................................................................179 ...........................................................................180 ..........................................................................................................................180 ..............................................................................................................................181 .............................................................................................................................181 .................................................................................................................................183

.....................................................................................................................184 ..................................................................................................................185 ....................................................................................................187 .......................................................................................................189

...................................................................................................189 ............................................................................................................................................189 ...............................................................................................189 ...................................................................................189

4. ....................................................................................................191

13. .........................................193 NEW DELETE...................................................................................................193 ......................................................................................................193 new delete.................................................................................................196 new....................................................................................................................197 ....................................................................................................197 ..........................................................................................................198

?...................................................................................................199 ............................................................................................................................199 .....................................................................................200 ...............................................................................200 .........................................................................................200 .................................................................200 ...........................................................................................................................................204

14. ..............................................................................205 ................................................................................................................................205 ........................................................................................................205

7

............................................................................................................................ 208 ....................................................................................................................... 208

........................................................................................................................................ 210 ...................................................................................................... 210 .............................................................................................................. 211 ............................................................................................. 211 ....................................................................................................... 212 ................................................................................................................. 213 .................................................................................................. 213

............................................................................................................................. 214 ................................................................................................................................. 214 ................................................................................................................................. 215 ........................................................................................................ 215 ............................................................................................................. 215 .................................................................................................................. 216

15. ..................................................................................................... 217 .................................................................................................................................... 217 , ? ...................................................................................................... 217 ................................................................................................................................... 220

, .................................................................................................. 223 .............................................................................................................. 223 ................................................................................................................................. 223 .................................................................................................................................................. 227 ........................................................................................................ 229

.................................................................................................................................... 229 ....................................................................................................................... 229 ............................................................................................................ 232 ................................................................................................................................... 233 : C++ ....................................................................................... 234

.............................................................................................................................. 236 VoidPtr ............................................................................................................................ 236 ........................................................................................................................ 237 ............................................................................................................ 238 ............................................................................................................................ 238 ........................................................................................................................................... 239 ............................................................................................. 239

............................................................................................................................................. 239 16. ................................................................................................................. 241 .............................................................................................................................................. 241 ................................................................................................................................................ 241 ................................................................................................................................. 242 ................................................................................................................................. 243 ....................................................................................................................... 244

................................................................................................ 245 ............................................................................................................... 245 ............................................................................................................. 245 .......................................................................................................... 246 ............................................................................................................................... 248 ........................................................................................................................................... 251 ................................................................................................................................... 251 ........................................................................................................... 251 ................................................................................................ 251 ? .................................................................................................... 252

..................................................................................... 252 .................................................................................................... 252 .............................................................................................................................. 253

8

....................................................................................................................................254 ...................................................................................................................254 .........................................................................................................................................255 .........................................................................................................255

...........................................................................................................................255 . JAVA C++ .....................................................................................................257

, , , . , , . , ego . , . , - , , .

, , , AP Professional. , , . , , !

(John Trudeau) Apple Computer, ++. , , , , , .

++ - . (Neal Goldstein), (Larry Rosenstein), (Eric Berdahl), (John Brugge), (Dave Simmons) (Dave Buell). , , .

Microsoft Corporation, , 90 90 . Microsoft, , , , . , Microsoft, Microsoft , .

(James Coplien), , Advanced C++ Programming Styles and Idioms . ++. , .

, (Bjarne Stroustrup) , . , SmallTalk , . ++ , , . , , . ++ - .

, . , , ( , IEEE Computer) ,

10

++. , , . , , .

. -, - , , , . ++ , , , , . , , . , .

, , , . ++, - : ( ), ( ), ( ) .. , (>). , , ? , .

, , . , , , , . : , . , .

1998 .

: ++? . , , ++.

1

++?

, 2 768 942 ++, , , . . ++ , . , . , 2 768 940 , ++. , , . - , . ++ .

. , , ++. , ++ - . , ; , , , , ( ). , , - . Annotated C++ Reference Manual, ARM .

, . ++: . ++ , . ++ , , , . . , , , . , ++ , . . , , , , .

++ ++ , . , , . -, ++ - . ! . ++ , (, , ) //. , , (, ) .

1

14

! . ++ , - . Smalltalk, , , ? ++ Cobol 90-, , . ++ , . , ++ . , ?

! , . , ? . ++ , . ( ++ ), . - , , . , Smalltalk Lisp, , - . ++ . , .

. ++ : , . ++ . . (, i++). , , :

cout

15

++, , : , . .

++ . . . , . , . , , . ; , . . , .

++ C++ , , . - ? , , - . , . C++. , , . . C++, :

.

.

.

C++, . , , .

C++. , C++ , . , / cout cin. 1 , C++ . 1 , , C++.

(indirection) , : , , , . . , (delegation), - . , C++ , , , . (pointer); . C++ . , , , ; ; ; , , . , , , .

, . - , C++

16

- . , (homomorphic derivation) C++. -. , , . C++ .

(memory space) , . C++ new delete, , . , , , . - , , Microsoft, Apple Taligent. , , . , C++. , , .

. . , C++ , , , , , .

. , , , , . . - C++.

C++ , ; . , , . 2 . 3 , . 4 ANSI , .

2 . , , .

3 C++. . , . , . , , .

4 C++ . , , C++, . , C++, , , - .

17

: . ? , , , . , , , . . , . , , - , .

, , . , . , .

(inline) , . :

class Foo {

public:

void MemberFn();

}; inline void Foo::MemberFn()

{

...

}

: class Foo {

public:

void MemberFnO {...};

};

, , . . , , . .

, , !

++

C++ , C++ ( ) . , , C++ . , - . Annotated Reference Manual . , . C++!

, , . : .

const const, , C++. , - , .

const, , . , . .

const int j = 17; //

j = 29; // ,

const int i; // ,

, , , . , , . i , . int , const int j=17; , int j(17).

, . , . , , .

const i = 17;

int& j = 1; // , j

2

20

, , j. , , . , , , .

const #define :

const int i = 17;

#define i 17;

, , . , - , . , . .

() : . C++ , .

class Foo {

public:

enum Status { kOpen = 1, kClosed };

};

// -

Foo::Status s = Foo::kOpen;

, . , kOpen kClosed . , . (, ).

, : . ; , .

const int* p;

int i = 17;

p = &i; //

*p = 29; //

. class foo {

public:

int x;

};

const foo* f = new foo;

f->x = 17; // ,

21

: , .

int i = 17;

int j = 29;

int* const p; // !

int* const p1 = &i; //

*p1 = 29; // ; , ,

//

p1 = &j; //

(- !) . .

int i = 17;

int j = 29;

const int* const p; // .

const int* const p1 = &i; //

*p1 = 29; //

p1 = &j; //

, .

void f(const int* p)

{

*p = 17; //

int i = 29;

p = &i; // , ?

}

// -

int i = 17;

f(&i); // ,

, , . -. , .

void f(const int& p)

{

p = 17; //

int i = 29;

p = i; // ( )

}

// -

int i = 17;

f(i); //

22

, , , .

void f(int*);

int i = 17;

const int* p = &i;

const int j = 29;

f(&i); // , i

f(p); //

f(&j); // , j -

, . f , .

this . , this , . const ; , , .

class foo {

private:

int x;

public:

void f() const;

void g();

};

void h(int*);

void m(foo*);

void foo::f();

{

x = 17; // :

this->g(); // : g

h(&x); // : h x

m(this); // : m()

}

this. foo this const foo* this;. . , g - foo, ; , . this. .

C++ const, . , this, . , , , , . ,

23

. : (), .

, C++ C. C++ , , . , .

int x = 17;

C++ int. ... int. . int , . , . , , .

C++, .

, .

{

int i;

foo f(constructor_args);

// i f

}

. . , , , , . :

{

int i;

foo f;

SomeFunction(&f);

}

SomeFunction , . SomeFunction - , f. SomeFunction , , - SomeFunction, !!! .

(heap), newnewnewnew.

foo* f = new foo(constructor_args);

. new . ? , :

24

- delete . ; , .

. , . , (dereferencing) . , .

{

foo f;

foo* p = &f;

f.MemberFn(); //

p->MemberFn(); //

p = new foo;

foo& r = *p; //

r.MemberFn(); // , p->MemberFn()

}

, . -> . , (. ->) (member selectors). , , , - .

delete , . ( ) , , , , , . , C++ new . . delete , . new , . delete , .

, , :

1. .

2. delete.

, : .

, , (, ). new ( , ) , , . . , new, , .

25

, , . Foo PFoo. Foo; . , . , operator Foo*() PFoo , Foo* , g().

class PFoo {

private:

Foo* f;

public:

PFoo() : f(new Foo) {}

~PFoo() { delete f; }

operator Foo*() { return f; }

}

void g(Foo*);

{

PFoo p;

g(p); // operator Foo*()

// p, Foo

}

, , , operator Foo*(), PFoo. .

. , - , . , , .

ANSI- (exception). , . , . , , .

C++ . , , . , C++ . , , .

:

;

;

;

;

.

26

, , . . , .

C++ , . , .

class Foo {

public:

static int y; //

static void GFn(); //

int x; //

Foo(); //

void Fn(); //

typedef int (*IntFn)(); //

enum Status { kOpen = 0, kClosed }; //

struct Bar { //

int a;

int b;

static void BarFn();

}

private:

void Hn();

};

. , a GFn() , Foo. Foo , :::

Foo::Foo()

{

GFn(); // Foo

}

void f()

{

Foo::GFn(); //

}

, IntFn, Status Bar Foo, . , r:

Foo::Bar b;

Foo::Bar::BarFn();

, .

, Foo Fn(), (instance) . - , . ->. (, , C++) ,

27

. , , :

Foo f;

f.Gfn(); // , Foo::GFn();

C++ . , . , ; public, private, protected . , : (public), C++.

, . ? :

.

-, .

-, .

C++ . , , C++ ( ). (- ), v-, .

C++ . . , , :

( ).

-.

.

, , , .

, . (private) (public). , , , . , .

, , .

C++ , . .

28

, . . :

// Foo.cpp

typedef int Symbol;

// Bar.cpp

typedef void (*Symbol)();

, . #include. Symbol , , -. , , . , .

// Foo.cpp

int Symbol;

// Bar.cpp

void (*Symbol)();

, . , , . ; . , .

// Foo.cpp

static int Symbol;

// Bar.cpp

static void (*Symbol)();

static, , ; .

, , :: :

::Fn(); //

int x = ::i; // x

::SomeType y; //

, , .

C++ . , . , , . .

, , .

void Fn();

29 void Fn(int);

void Fn(long); // , long int

int Fn(int); //

int Fn(char*); // ,

void Fn(int, char*);

void Fn(char*, int); // ,

void Fn(char* s, int x, int y = 17); //

Fn(hello, 17); //

, . ( =17) , ( ).

, , . , .

class Foo {

public:

void Fn();

void Fn() const; // !

};

Foo* f = new Foo;

f->Fn(); //

const Foo* f1 = f;

f1->Fn(); //

C++ ( , ) , , , . , . , (visibility) C++.

; . , .

, , .

class Mixin {

private:

int x;

protected:

int y;

public:

Mixin();

Void a();

};

30 class Foo : private Mixin {...};

class Bar : public Foo {...};

Mixin (). Foo, Mixin::A(). Mixin , Foo ( r ). Foo (), Bar .

, .

class Foo {

protected:

virtual void Fn();

};

class Bar : public Foo {

public:

virtual void Fn();

};

Foo Fn() , . . .

class Foo {

private:

int x;

public:

void Fn();

};


private:

int x; //

public:

void Fn(); //

};

//

Bar *b = new Bar;

b->Fn(); // Bar::Fn()

Foo* f = b; // , Foo

f->Fn(); // Foo::Fn()

. Foo Foo::. Bar r::. , , . Fn() , . C++ .

, . , , . . , virtual .

31

, , . DWIMNIS: Do what I mean, not what I say ( , , , ). , C++ , ( ) . Bar::Fn():

class Foo {

public:

virtual void Fn();

};

class Bar {

public:

void Fn(); //

};

Bar* b = new Bar;

b->Fn(); // Bar::Fn()

Foo* f = b;

f->Fn(); // Bar::Fn()

. -, , Foo::Fn(). -, , Fn() , . .

, , , . ? ? , .

class Foo {

public:

virtual void Fn();

virtual void Fn(char*);

};

class Bar {

public:

virtual void Fn(int); // ,

};

, - , . :

Fn() r* , void Fn(int). Bar*.

Bar* Foo* , Foo, void Fn(int). , , Bar::Fn() . , virtual .

- , , , , - . , . . , : , , .

32

- (friend). , , , . , . ; - , .

class Foo;

class BarBar {

public:

int Fn(Foo*);

};

class Foo {

friend void GlobalFn(); //

friend class Bar; //

friend int BarBar::Fn(Foo*); //

friend class DoesNotExist; // .

private:

int x;

struct ListNode {

ListNode* next;

void* datum;

ListNode() : next(NULL), datum(NULL) {}

} head;

protected:

int y;

public:

void G();

};

void GlobalFn()

{

Foo* f = new Foo;

f->x = 17; // -

}

class Bar {

private:

Foo* f;

public:

Bar() : f(new Foo) {}

void WalkList();

};

void Bar::WalkList()

{

Foo::ListNode* n = f->head.next;

for (; n != NULL; n = n->next)

cout datum x; }

33

, public, protected private. , ; , . Foo . Foo, . , - DoesNotExist. , , . Foo. , . , .

, , , .

, , , , . , (, ).

, C++ , .

, , .

class Foo {

public:

Foo();

};

class Bar : public Foo { // 1.

public:

Bar();

};

class BarBar {

private:

Foo f; // 2.

};

Foo f; // 3. Foo

Foo* f1 = new Foo; // 3. ,

(. ) Bar - Foo, Foo . , f BarBar, Foo . , Foo .

, , . , . , . -

34

, , , , .

class Foo {

public:

Foo(char*);

};

Foo f; // !


public:

Bar();

};

Bar::Bar()

{

// ! Foo

}

, C++ : . , .

class Foo {

public:

Foo(char*);

};


public:

Bar(char*);

};

class BarBar {

private:

Foo f;

int x;

public:

BarBar();

};

Bar::Bar(char* s) : Foo(s) {...}

BarBar::BarBar : f(Hello), x(17) {...}

Bar Foo. , . Bar , , Foo. BarBar ( ) f . ( ):

BarBar::BarBar() : f(Hello) { x = 17; }

35

0 ( C++) int , 17. - . , , , .

, (, , ). , , .

, , . . , , :

1. ( , : , ).

2. .

3. , .

, ... . . , . , . , , .

(copy constructor) :

class Foo {

public:

Foo(const Foo&);

};

Foo::Foo(const Foo& f)...

. .

void Fn(Foo f) {...}

void Gn(Foo& f) {...}

Foo f;

Foo f1(f);

Foo f2 = f; // , !

Fn(f); //

const Foo f3;

Gn(f3); //

//

. Foo f1(f); Foo, Foo . ,

36

Foo . , ; , . , Foo ; , .

Foo f2 = f - =, . , , : ? , . , , .

Fn() Foo. , Fn(). , .

Gn(), , , C++ - :

, ! , . , , , . Gn() , .

.

1. , .

2. , .

, ... . . , ? , .

, , . , , , . .

class Foo {...};


private:

Foo f;

public:

Bar(const Bar&);

};

// ,

Bar::Bar(const Bar& b)

{

// !

//

//

}

// ,

Bar::Bar(const Bar& b) : Foo(b), f(b.f) {...}

37

, . Foo . 99 100 , ; , . , . , ( b Foo Foo(b)).

. , .

class Serialized {

private:

static int NextSerialNumber;

int serialNumber;

public:

Serialized(const Serialized&);

Serialized();

int SerialNumber();

};

// Serialized.cpp

int Serialized::NextSerialNumber = 0;

Serialized::Serialized() : serialNumber(NextSerialNumber++)

{

}

Serialized::Serialized(const Serialized&) : serialNumber(NextSerialNumber++)

{

}

int Serialized::SerialNumber()

{

return serialNumber;

}

ac , , , .

, . ; new ( , ). , , . , . - . , ( ) .

class Foo {

protected:

Foo();

};

38 class Bar : public Foo {

public:

Foo* Fn();

};

Foo Bar::Fn()

{

return new Foo; //

}

, , Foo . , ! . Foo Bar Foo. , .

(anonymous instance) , ... , .

struct Point {

int X;

int Y;

Point(int x, int y) : X(x), Y(y) {}

};

double distance(Point p)

{

return sqrt(double(p.X) * double(p.X) + double(p.Y) * double(p.Y));

}

double d = distance(Point(17, 29));

distance() . . , .

Point, .

. C++, . , , . , , . , :

1. - 0.

2. , , .

3. . , main() .

39

4. , ( .), . 3 , , .

. . .

// file1.cpp

Foo foo;

Foo* f = &foo;

// file2.cpp

extern Foo* f;

Foo f1(*f); //

, . F* f = &foo; , (-) . , , foo . , , file1.cpp file2.. file2.cpp , f 0 (NULL ), .

, .. .h , .. 0 1 , .. 1 0 .

// Library.h

class Library {

private:

static int count;

static void OpenLibrary();

static void CloseLibrary();

public:

Library();

~Library();

};

static Library LibraryDummy;

inline Library::Library()

{

if (count++ == 0)

OpenLibrary();

}

inline Library::~Library()

{

if (--count == 0)

CloseLibrary();

}

// Library.cpp

int Library::count = 0; //

int aGlobal;

40 Foo* aGlobalFoo;

void Library::OpenLibrary()

{

aGlobal = 17;

aGlobalFoo = new Foo;

}

void Library::CloseLibrary()

{

aGlobal = 0;

delete aGlobalFoo;

aGlobalFoo = NULL;

}

. : .h ., - Library.cpp. , , . , LibraryDummy. ., Library.h, LibraryDummy . main() exit() . LibraryDummy. , OpenLibrary() CloseLibrary() .

, iostream. , , , .

, ( , ) delete. .

, . , , , , , ..

, . , , .

main() exit().

C++ . base* ( ), , .

class Foo {

public:

~Foo();

};

41 class Bar : public Foo {

private:

int* numbers;

public:

Bar() : numbers(new int[17]) {...}

~Bar();

};

Bar* b = new Bar;

delete b; // Bar::~Bar()

Foo* f = new Bar;

delete f; // ! Foo::Foo()!

f , numbers, , . , ; (, , void*) Bar: :~().

, . ! . , , 20 , 220 ! C++ .

: . , .

, delete, , . , , , - .

class Foo {

public:

~Foo();

};

Foo* f = new Foo;

f->Foo::~Foo();

, C++.

C++ . , .

=.

Foo f;

Foo f1;

f1 = f;

. f f1 - , : ,

42

f, , f1. . Foo , C++ . = , . , , , =. , , , .

class String {

private:

char* s;

public:

String(char*);

~String();

void Dump(ostream& os);

};

String::String(char* str) : s(NULL)

{

if (str == NULL) { // NULL

s = new char[1];

*s = \0;

}

else {

s = new char[strlen(str) + 1];

strcpy(s, str);

}

}

String::~String()

{

delete s;

}

void String::Dump(ostream& os)

{

os s. , , . , Goodbye, String* s2 = new String( "Goodbye");. ; s1 , s1. s2->s. s2->s . s2, . C++!

43

, . , , . = .

, , , . = , = . , . = . =.

Foo f;

Foo f1 = f; // ; f1

f1 = f; // : f1

= , , . , , = . :

1. . = = .

2. . = = .

. , . .

= = . =, : & X::operator=(const X&).

class String {

private:

char* s;

public:

String(char*);

~String();

String(const String&); // ,

String& operator=(const String&);

void Dump(ostream& os);

};

String::String(char* s) : s(NULL)

{

if (str == NULL) { // NULL

s = new char[1];

*s = \0;

}

else {

s = new char[strlen(str) + 1];

strcpy(s, str);

44 }

}

String::~String()

{

delete s;

}

String::String(const String& s1) : s(NULL)

{

s = new char[strlen(s1.s) + 1];

strcpy(s, s1.s);

}

String& String::operator=(const String& s1)

{

if (this == &s1) return *this;

delete s; //

s = new char[strlen(s1.s) + 1];

strcpy(s, s1.s);

return *this;

}

void String::Dump(ostream& os)

{

os

45 public:

Foo& operator=(const Foo&);

};

class Bar {

public:

// =

};

class FooBar {

private:

Foo f;

Bar b;

public:

FooBar& operator=(const FooBar&);

};

FooBar& FooBar::operator=(const FooBar& fb)

{

if (this == &fb) return *this;

f = fb.f; // = Foo

f = fb.b; // =

return *this;

}

, , =. .

. , , . :

class Foo {...}


public:

Bar& operator=(const Bar&);

};

Bar& Bar::operator=(const Bar& b)

{

if (this == &b) return *this;

this->Foo::operator=(b); // -?

return *this;

}

, (, *((Foo)this)=b;), . . , , Bar Foo . , Foo::operator= . , , Foo::operator=.

= = . , . & X::operator=(const &) , .

46 class String {

//

public:

String& operator=(const String&); //

String& operator=(char*); //

String& operator=(int); // atoi()

};

= . String char* , . . , ( ) .

C++ . , Add , + . , , . -, . -, . , .

(, +) : . C++ operator, .

class Foo {...}

Foo x, y, z;

z = x + y; // ()

z = operator+(x, y); // ( )

z = x.operator+(y); // ( )

, , , , , . . . , , , . ( ! ~) . , ( , . ->).

(, ). , , ( ). , C++. - #$%^&, C++ .

, , , +. , , , .

47

, .

class String {

friend String& operator+(const String&, const String&);

private:

char* s;

public:

// ..

}

String& operator+(const String& s1, const String& s2)

{

char* s = new char[strlen(s1.s) + strlen(s2.s) + 1];

strcat(s, s1.s, s2.s);

String newStr(s);

delete s;

return newStr;

}

String s1 = Hello;

String s2 = Goodbye;

String s3 = s1 + s2;

, ( ). . operator+ , s, : char*, , - . operator+ String, , String.

, , =, [], () -> .

, 1 .

class String {

private:

char* s;

public:

// ..

String& operator+(const String&) const;

};

String& String::operator+(const String& s1) const

{

char* s2 = new char[strlen(s1.s) + strlen(s) + 1];

strcat(s2, s1, s);

String newStr(s2);

delete s2;

return newStr;

}

48 String s1 = Hello;

String s2 = Goodbye;

String s3 = s1 + s2;

. , , ? : , . :

1. (, int double).

2. , .

, . , .

49 {

// , ,

// ,

return atoll(s);

}

String s(1234);

long x = s; // operator long()

. , , , . , long(). Foo, Foo String, operator Foo(). : , , - ? , . , . . int? , int , . , . . , , . .

. , . , , . , . , , .

class String {

private:

char* s;

public:

operator const char*() const { return s; }

operator char*():

};

String::operator char*()

{

char* newStr = new char[strlen(s) + 1];

strcpy(newStr, s);

return newStr;

}

, , .

C++ , , , . , :

1. , .

50

2. , , . , .

3. , .

, , - . . , , .

, . , . , , . , . 3, .

-> -> . .

class Pointer {

private:

Foo* f;

public:

Pointer(Foo* foo) : f(foo) {}

Foo* operator->() const { return f; }

};

Pointer p(new Foo);

p->MemberOfFoo();

Foo. (*-) >, ->. ->, ; , ->. , ->. /, - , ->. , -> ( Foo*) , . , .

class Pointer2 {

private:

Pointer p;

public:

Pointer(Foo* foo) : p(foo) {}

Pointer operator->() const { return p; }

};

Pointer2 p(new Foo);

p->MemberOfFoo();

51

-> :

1. Pointer2::operator-> Pointer.

2. Pointer::operator-> Foo.

3. Foo* .

, . . , , .

[] [] , .

class String {

private:

char* s;

public:

String(char*);

char operator[](int n) const; // n-

};

char String::operator[](int n)

{

//

return s[n];

}

[] , .

struct Index3 {

int X, Y, Z;

Index3(int x, int y, int z) : X(x), Y(y), Z(z) {}

};

class Array3D { // String

private:

//

public:

String& operator[](const Index3&);

};

String s = anArray[Index3(17, 29, 31)];

[] , .

() , , . , , . , C++ . () , . , - .

52 class Function {

public:

int operator()(char*);

};

int Function::operator()(char* s)

{

cout

53 };

void* operator new(size_t bytes, Pool* p)

{

return p->Allocate(bytes);

}

extern Pool* DefaultPool;

Foo* f = new(DefaultPool) Foo;

new Foo; , .

delete delete new . , :

1. void operator delete(void* address);

2. void operator delete(void* address, size_t bytes);

; , . , ... ! :

class Foo {

private:

int x;

public:

~Foo(); //

};


private:

int y;

public:

~Bar();

};

Bar* b = new Bar;

delete b; //

Foo* f = new Bar;

delete f; // Foo, Bar

. , . :

1. .

2. .

3. , , , .

, , , ( , v-). ? .

delete, new, , . , .

54

new, delete . , , , .

, . , , , , , C++ . , , . , , , - . . C++, .

? - ( ) :

class ListNode {

private:

ListNode* next;

void* data;

public:

ListNode(void* d, ListNode* n = NULL) : next(n), data(d) {}

~ListNode() { delete next; }

void* Data() { return data; }

ListNode* Next() { return next; }

};

- ?

, void*. , , . - - :

for (ListNode* n = listHead; n != NULL; n = n->Next())

f((Foo*)n->Data());

, void* , Foo*? , , , . , , . , - ? , , .

3

56

, , . , , , , . delete void* , .

, . void* , . , ListNode , . , .

, . , Foo - ListOfFoos. , Foo . -, , ? , , . , .

#define: #define ListNode(Type) \

class ListNode##Type { \

private: \

ListNode##Type* next; \

Type* data; \

public: \

ListNode##Type(Type* d, ListNode* n = NULL) : next(n), data(d) {} \

~ListNode() { delete next; } \

void* Data() { return data; } \

ListNode* Next() { return next; } \

};

\, , . ## . , . . (inline), , . . #define , , . , , - , .

#define. , . . . C++ . . , \ ##.

57

, , (parameterized). ( ) .

, template , Type ( ). , Type ( ) , . ListNode, , :

template

class ListNode {

private:

ListNode* next;

Type* data;

public:

ListNode(Type* d, ListNode* n = NULL) : next(n), data(d) {}

~ListNode() { delete next; }

Type* Data() { return data; }

ListNode* Next() { return next; }

};

ListNode list = new ListNode (new Foo);

Foo* f = list->Data(); //

, . , .

template.... , . , , .h. ., ( ., ).

//

template

Type* fn(Type* t);

//

template

Type* fn(Type* t) {

// , Type

//

}

Foo* f = fn(new Foo);

, . , .

58

( < >). ListNode , .

template

class ListNode {

private:

ListNode next;

Type* data;

public:

ListNode(Type* d, ListNode* n = NULL);

~ListNode();

Type* Data();

ListNode* Next();

};

template

ListNode::ListNode(Type* d, ListNode* n = NULL)

: next(n), data(d)

{

}

template

ListNode::~ListNode()

{

delete next;

}

template

Type* ListNode::Data()

{

return data;

}

template

ListNode* ListNode::Next()

{

return next;

}

: .h. , ., . .

< > , C++ . , , :

1. class .

2. .

3. .

, .

59

. , C++ , C++... . .

, . , . , . , . , . -, .

! , , , . , . , .

template

class B {...};

template

class A {

B* member; // !

};

. . , ; , .

, . , ; , . , , APL-. , . . .

, , 1000 . 1000 . .

, , . , .h. .

, - , . , , , . . , .h ?

60

, . , 99 100 , . - . , .

. . , . ( , ), - : .

. .

class UnsafeNode { // ListNode

private:

UnsafeNode* next;

void* data;

public:

UnsafeNode(void* d, UnsafeNode* n);

virtual ~UnsafeNode();

UnsafeNode* Next();

void* Data();

};

template

class SafeNode : private UnsafeNode {

public:

SafeNode(Type* d, SafeNode* n) : UnsafeNode(d, n) {}

virtual ~SafeNode() { delete (Type*)Data(); }

SafeNode* Next() { return (SafeNode*)UnsafeNode::Next(); }

Type* Data() { return (Type*)UnsafeNode::Data(); }

. , C++. Next() Data() , ; , . , . , , .

, . , . Next() Data(), , .

:

61

. . ; .

UnsafeNode. SafeNode UnsafeNode SafeNode. SafeNode SafeNode ! . UnsafeNode UnsafeNode, SafeNode. .

// SafeList.h

class UnsafeNode; //

template

class SafeList { // UnsafeNode

private:

UnsafeNode* head;

public:

SafeList() : head(NULL) {}

~SafeList();

UnsafeNode* Cursor(); //

Type* Next(UnsafeNode*&); //

void DeleteAt(UnsafeNode*&); //

void InsertFirst(Type*); //

void InsertBefore(UnsafeNode*&); //

void InsertAfter(UnsafeNode*&); //

};

// SafeList.cpp

class UnsafeNode { // ListNode

private:

UnsafeNode* next;

void* data;

public:

UnsafeNode(void* d, UnsafeNode* n);

virtual ~UnsafeNode();

UnsafeNode* Next();

void* Data();

};

SafeList , . ( InsertFirst) , . , , ( ). , . , , SafeList. , , . : UnsafeNode , . . , , , . , .

, . , .

, , . , , . , , . :

if ( ) {

;

}

else {

- ;

}

, . , , . , . . , .

ANSI : ANSI , C++, . , ? , , . , . , .

: C++. : . : , . .

, , , .

, . throw. , Gotcha.

enum Gotcha { kTooLow, kTooHigh };

void fn(int x) throw(Gotcha) {

4

64 if (x < 0)

throw kTooLow; //

if (x > 1000)

throw kTooHigh; //

// -

}

. : , , . , , . Gotcha. , , , . .

.

void Fn() throw(int); //

// - .cpp

void Fn() throw(int) {

//

}

, .

, . , .

void fn(); //

, , . , , .

void fn() throw(); //

, , .

void fn() throw(int, Exception_Struct, char*);

, , , .

void fn() throw;

. , ( !) . :

65 void f1(int) throw();

void f1(int) throw(Exception); // !

2 (, , ) (overloading) (overriding). , , ( - , ; ). .

class Foo {

public:

virtual Fn() throw(int);

};


public:

virtual Fn() throw(char*); // !

};

, . , Foo*, int, , r, .

: . , .

, . . unexpected(). terminate(), , , . except.h :

typedef void (*unexpected_function)();

unexpected_function set_unexpected(unexpected_function excpected_func);

typedef... . set_unexpected() . set_unexpected() . , . , .

unexpected_function my_handler(void) {

//

}

{ //

unexpected_function old_handler = set_unexpected(my_handler);

//

set_unexpected(old_handler);

}

- , return . , , .

66

, try catch, (handlers).

try {

// ,

}

catch (Exception_Type t) {

// Exception_Type

}

catch (...) {

//

}

, ( ) , . , try-, , , . ; , .

. catch , , .

try- , . , , . ( ): goto . , .

catch(int exception) {

// -,

throw(Help!); // char*

}

.

, terminate(). , ? terminate() abort(), . set_terminate(). except.h :

typedef void (*terminate_function)();

termination_function set_terminate(terminate_function t_func);

typedef... . set_terminate() , abort() terminate(). set_terminate() , set_terminate().

67

. , .

, try/catch , , .

{

try {

try {

try {

//

}

catch(...) {

}

}

catch(...) {

}

}

catch(...) {

}

}

, .

! , throw. , , . , Ctrl, , , . , , ; .

(unwinding the stack). throw catch.

void fn() throw(int) {

Foo aFoo;

// - !

throw(bad_news);

}

, aFoo. try- .

{

try {

Bar b;

fn(); //

}

68 catch(int exception) {

// , , b

}

}

, , try-. , . , .

, try-, . , , . , .

( new) . . , , .

class TempFoo {

private:

Foo* f;

public:

TempFoo(Foo* aFoo) : f(aFoo) {}

~TempFoo() { delete f; }

};

try {

TempFoo tf(new Foo);

// ..

}

catch(...) {

// Foo tf

}

:

class Foo {...}


private:

A a;

B b;

public:

Bar();

};

Bar::Bar()

{

X x;

throw(bad_news);

Y y;

}

69

, ( ), . r . , (Foo) ( b) , . x. , . Bar , .

, b . Foo , b, Bar .

, . , , .

, . , .

. try/catch , . .

, , . , , - ( ). , : . , , .

- , , . 99% , . , , , , , . , .

throw catch, , . , . - , throw:

f()

{

if (pool->Allocate(size) == NULL)

//

}

? ++ . ( ) ++ , . , , . , . , .

2

, ->, . :

class Foo {

public:

void MemberOfFoo();

};

Foo* aFoo = new Foo;

aFoo->MemberOfFoo();

, -> , aFoo. C++ , , . -> , ( MemberOfFoo()). (Foo) ->. , ; ->.

-> C++, , ( .), . 2, , .

C++ , int, double . . , int , Integer, :

class Integer {

private:

int value;

public:

Integer() : value(0) {}

Integer(int v) : value(v) {}

operator int() { return value; }

Integer operator+(Integer i) { return Integer(value + i.value); }

Integer operator+=(Integer i) { value += i.value; return *this; }

// ..

};

int f(int);

f(Integer(17)); // int()

5

74

Integer , int Integer. , char* ( atoi()) . Integer int (, int), int() . . ! int Integer. , int. .

? , C++ ( -) , *- , ( ; , !). , . , .

class PFoo {

private:

Foo* foo;

public:

PFoo() : foo(NULL) {}

PFoo(Foo* f) : foo(f) {}

operator Foo*() { return foo; }

PFoo operator+(ptr_diff offset) { return PFoo(foo + offset); }

PFoo operator+=(ptr_diff offset) { foo += offset; return *this; }

ptr_diff operator-(PFoo pf) { return foo - pf.foo; }

// ..

};

! , Foo*! . , , , ptr_diff . , Foo, PFoo Foo*... ? . .

PFoo pf(new Foo*);

pf->MemberOfFoo(); //

((Foo*)pf)->MemberOfFoo(); // , !

Foo*() PFoo , Foo*. , , -> . , , .

, , ?

1. , . , , . PFoo Foo .

2. , (, size_t ptr_diff). , .

3. ->. .

75

. , ptr_diff.

-> , -> . , 2, PFoo ->. . f() , , , Foo*() .

class PFoo {

private:

Foo* foo;

public:

PFoo() : foo(NULL) {}

PFoo(Foo* f) : foo(f) {}

operator Foo*() { return foo; }

Foo* operator->() { return foo; }

};

void f(Foo*);

PFoo pf(new Foo);

f(pf); // operator Foo*()

pf->MemberOfFoo(); // operator->()

, pf->MemberOfFoo(), . -> , ->. , pf , ->. , . , , . - (, int), . , -, . . , , , :

PFoo operator->() { return *this; }

-> . C++ .

, -, , Foo*: , -> , Foo* .

.

template

class SP {

private:

Type* pointer;

public:

76 SP() : pointer(NULL) {}

SP(Type* p) : pointer(p) {}

operator Type*() { return pointer; }

Type* operator->() { return pointer; }

};

void f(Foo*);

Ptr pf(new Foo);

f(pf); // operator Type*()

pf->MemberOfFoo(); // operator->()

, Foo. . , .

C++ , :

1. P, ? . .

2. operator P()? . .

3. , - P? ! operator Bar*() Bar*, Foo*. Ptrpf2(Foo*(pb.operator Bar*())), Bar* Foo* , .

, , . (inline) operator Bar*() P(Foo*) , ; ( , ) , . : , , .

, . , .

class PVoid { // void*

protected:

void* addr;

public:

PVoid() : addr(NULL) {}

PVoid(void* a) : addr(a) {}

operator void*() { return addr; }

};

class Foo : public PVoid {

public:

PFoo() : PVoid() {}

PFoo(Foo* p) : PVoid(p) {}

operator Foo*() { return (Foo*)addr; }

Foo* operator->() { return (Foo*)addr; }

77 };

class Pbar : public PFoo {

public:

PBar() : PFoo() {}

PBar(Bar* p) : PFoo(p) {}

operator Bar*() { return (Bar*)addr; }

Bar* operator->() { return (Bar*)addr; }

};

pBar pb(new Bar);

pFoo pf(pb); // , PBar PFoo

pf->MemberOfFoo(); // PFoo::operator->

, / ( ) , r::operator->() PFoo::operator->(). , , Ptr.

, / . , ++ --.

template

class Ptr {

private:

Type* pointer;

public:

Ptr() : pointer(NULL) {}

Ptr(Type* p) : pointer(p) {}


ptr_diff operator-(Ptr p) { return pointer p.pointer; }

ptr_diff operator-(void* v) { return ((void*)pointer) v; }

Ptr operator-(long index) { return Ptr(pointer index); }

Ptr operator-=(long index) { pointer -= index; return *this; }

Ptr operator+(long index) { return Ptr(pointer + index); }

Ptr operator+=(long index) { pointer += index; return *this; }

};

, ptr_diff . , , . , . : C++, , , . , .

- , , , . , , . , .

78

? , , , . *-; . C++ , .

template

class Ptr {

private:

Type* pointer;

public:




Type* operator->() { return pointer; }

};

, -> . , . . , .

, , . , , , .

NULL :

template

class SPN {

private:

Type* pointer;

public:

SPN() : pointer(NULL) {}

SPN(Type* p) : pointer(p) {}


Type* operator->()

{

if (pointer == NULL) {

cerr

79

, , NULL. .

#indef , , if- #ifdef, . -> .

. :

template

class Ptr {

private:

Type* pointer;

public:

enum ErrorType { DereferenceNil };




Type* operator->() throw(ErrorType)

{

if (pointer == NULL) throw DereferenceNil;

return pointer;

}

};

( ErrorType , ; .) . , .

, (screamer). , - NULL.

template

class AHHH {

private:

Type* pointer;

static type* screamer;

public:

AHHH() : pointer(NULL) {}

AHHH(Type* p) : pointer(p) {}

Operator Type*() { return pointer; }

Type* operator->()

{

if (p == NULL) return screamer;

return pointer;

80 }

};

? . , screamer Type* , ( ) rr . , .

, . operator Type*() operator->(), . , .

(out-of-line) .

template

class PTracer {

private:

Type* pointer;

public:

PTracer() : pointer(NULL) {}

PTracer(Type* p) : pointer(p) {}

operator Type*();

Type* operator->();

};

template

#ifdef DEBUGGING

inline

#endif

PTracer::operator Type*()

{

return pointer; //

}

template

#ifdef DEBUGGING

inline

#endif

Type* PTracer::operator->()

{

return pointer; //

}

, .

-> cout cerr, .

81

Type* -> .

template

class SPCS {

private:

Type* pointer;

static int conversions;

static int members;

public:

SPCS() : pointer(NULL) {}

SPCS(Type* p) : pointer(p) {}

operator Type*() { conversions++; return pointer; }

Type* operator->() { members++; return pointer; }

int Conversions() { return conversions; }

int Members() { return members; }

};

- . Foo.cpp: // Foo.cpp

int Ptr::conversions = 0;

int Ptr::members = 0;

, #ifdef, .

. , (master pointers), , . , ( ), () . . , , . , , Counter.

class Counter {

protected:

Counter() : conversions(0), members(0) {}

Counter(const Counter&) : conversions(0), members(0) {}

Counter& operator=(const Counter&) { return *this; }

public:

int conversions;

int members;

int Conversions() { return conversions; }

int Members() { return members; }

};

template

class SPOP {

private:

Type* pointer;

82 public:

SPOS() : pointer(NULL) {}

SPOP(Type* f) : pointer(f) {}

operator Type*() { pointer->conversions++; return pointer; }

Type* operator->() { pointer->members++; return pointer; }

};

, .

, , . , ReadObject() , pointer. , .

typedef unsigned long DiskAddress; //

template

class CP {

private:

DiskAddress record_number;

Type* pointer;

void ReadObject(); //

public:

CP(DiskAddress da) : pointer(NULL), record_number(da) {}

CP(Type* f) : pointer(f), record_number(f->RecordNumber()) {}

operator Type*()

{

if (pointer == NULL) this->ReadObject();

return pointer;

}

Type* operator->()

{

if (pointer == NULL) this->ReadObject();

return pointer;

}

};

, , . , , , , , . , , , .

. :

1. .

2. , new, .

83

, . ( ), 31 . , 32 . , , , , , .

: , . C++, , , .

. , . , ? ( )? ? ? ? .

. , ,

Documents

C++