Справочное руководство по C++

Страустрап Бьярн

{

 if (p-›n › 1) {

p-›n--;

p = new srep;

 }

 else if (p-›n == 1)

delete p-›s;

 p-›s = new char[strlen(s)+1];

 strcpy(p-›s, s);

 p-›n = 1;

 return *this;

}

string& string::operator=(string& x)

{

 x.p-›n++;

 if (--p-›n == 0) {

delete p-›s;

delete p;

 }

 p = x.p;

 return *this;

}

ostream& operator‹‹(ostream& s, string& x)

{

 return s ‹‹ x.p-›s ‹‹ " [" ‹‹ x.p-›n ‹‹ "]\n";

}

istream& operator››(istream& s, string& x)

{

 char buf[256];

 s››buf;

 x = buf;

 cout ‹‹ "echo: " ‹‹ x ‹‹ "\n";

 return s;

}

void error(char* p)

{

 cout ‹‹ p ‹‹ "\n";

 exit(1);

}

char& string::operator[](int i)

{

 if (i‹0 || strlen(p-›s)‹i) error("index out of range");

 return p-›s[i];

}

main

{

 string x[100];

 int n;

 cout ‹‹ "here we go\n";

 for (n = 0; cin››x[n]; n++) {

string y;

if (n==100) error("too many strings");

cout ‹‹ (y = x[n]);

if (y=="done") break;

 }

 cout ‹‹ "here we go back again\n";

 for (int i=n-1; 0‹=i; i--) cout ‹‹ x[i];

}

b7_2_8.cxx

#include ‹stream.hxx›

struct employee {

 friend class manager;

 employee* next;

 char* name;

 short department;

 virtual void print;

};

struct manager: employee {

 employee* group;

 short level;

 void print;

};

void employee::print

{

 cout ‹‹ name ‹‹ "\t" ‹‹ department ‹‹ "\n";

}

void manager::print

{

 employee::print;

 cout ‹‹ "\tlevel " ‹‹ level ‹‹ "\n";

}

void f(employee* ll)

{

 for (; ll; ll=ll-›next) ll-›print;

}

main

{

 employee e;

 e.name = "J. Brown";

 e.department = 1234;

 e.next = 0;

 manager m;

 m.name = "J. Smith";

 m.department = 1234;

 m.level = 2;

 m.next = &e;

 f(&m);

}

b7_7.cxx

#include ‹stream.hxx›

struct base { base; };

struct derived: base { derived; };

base:: base

{

 cout ‹‹ "\tbase 1: this=" ‹‹ long(this) ‹‹ "\n";

 if (this == 0) this = (base*)27;

 cout ‹‹ "\tbase 2: this=" ‹‹ long(this) ‹‹ "\n";

}

derived::derived

{

 cout ‹‹ "\tderived 1: this=" ‹‹ long(this) ‹‹ "\n";

 if (this == 0) this = (derived*)43;

 cout ‹‹ "\tderived 2: this=" ‹‹ long(this) ‹‹ "\n";

}

main

{

 cout ‹‹ "base b;\n";

 base b;

 cout ‹‹ "new base;\n";

 new base;

 cout ‹‹ "derived d;\n";

 derived d;

 cout ‹‹ "new derived;\n";

 new derived;

 cout ‹‹ "new derived;\n";

 new derived;

 cout ‹‹ "at the end\n";

}

b8_3_3.cxx

#include ‹xstream.hxx›

extern void exit(int);

void error(char* s, char* s2)