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Revision as of 16:37, 14 June 2023

435 bytes removed ,  11 months ago
Updated formatting to use <syntaxhighlight>.
(Moved Polymorphism C example to here)
 
(Updated formatting to use <syntaxhighlight>.)
 
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{{Programming-example-page|Polymorphism}}
<syntaxhighlight lang="c">/* After reading this you may understand */ ▼
/* why Bjarne Stroustrup's invented C++ */▼
#if defined( _WIN32 ) || defined( MSC_VER )▼
#define FN_PTR(x) (& x)▼
#else▼
#define FN_PTR(x) (x)
#endif▼
 
typedef struct Point▼
'''Compiler:''' GCC, MSVC, BCC, Watcom
{
int x;▼
int ry;▼
void (*dtor)(); /* virtual */▼
void (*print)(); /* virtual */▼
} Point;▼
 
Point* Point_new0()
'''Libraries:''' Standard
{
▲ /* After reading this you may understand */
Point* pthis = (Point*) malloc( sizeof( Point ) );▼
▲ /* why Bjarne Stroustrup's invented C++ */
memcpymemset(pthis, p0, sizeof( Point ) );▼
▲ #if defined( _WIN32 ) || defined( MSC_VER )
#definepthis->dtor = FN_PTR(x) (& xPoint_dtor);
pthis->print = FN_PTR(Point_print);▼
▲ #else
}
▲ #define FN_PTR(x) (x)
▲ #endif
 
Point* Point_new1(int x0)
▲ typedef struct Point
{
Point* pthis = malloc( sizeof( Point ) );
▲ int x;
pthis->x = int yx0;
pthis->y = 0;▼
▲ void (*dtor)(); /* virtual */
pthis->dtor = FN_PTR(Point_dtor);▼
▲ void (*print)(); /* virtual */
pthis->print = FN_PTR(Point_print);▼
▲ } Point;
}
 
Point* Point_new0Point_new2(int x0, int y0)
{
Point* pthis = (Point*) malloc( sizeof( Point ) );
memset(pthis, 0, sizeof( Point->x )= )x0;
pthis->dtor y = FN_PTR(Point_dtor)y0;
pthis->printdtor = FN_PTR(Point_printPoint_dtor);
pthis->dtor print = FN_PTR(Point_dtorPoint_print);▼
}
}
 
void Point_delete(Point** Point_new1(int x0pthis)
{
if(pthis && *pthis)▼
{
Point(* pthis = (Point*) malloc->dtor( sizeof( Point ) );
free(*pthis); *pthis->x = x0NULL;
▲ pthis->y = 0;
▲ pthis->dtor = FN_PTR(Point_dtor);
▲ pthis->print = FN_PTR(Point_print);
}
}
 
Point* Point_new2Point_copy(int x0, intPoint* y0p)
{
Point* pthis = (Point*) malloc( sizeof( Point ) );
memcpy(pthis, p, sizeof( Point ) );
pthis->x = x0;
pthis->ydtor = y0FN_PTR(Point_dtor);
pthis->dtor print = FN_PTR(Point_dtorPoint_print);
return pthis->print = FN_PTR(Point_print);
}
 
int void Point_deletePoint_getX(Point** pthis) { return pthis->x; }
int Point_getY(Point* pthis) { return pthis->y; }▼
{
int Point_setX(Point* pthis, int x0) { pthis->x = x0; }▼
▲ if(pthis && *pthis)
int Point_setY(Point* pthis, int y0) { pthis->y = y0; }▼
{
void Point_print() { printf("Point\n"); }▼
(*pthis)->dtor();▼
void Point_dtor() {}▼
free(*pthis); *pthis = NULL;
}
}
 
Point* Point_copy(Point* p)
{
▲ Point* pthis = (Point*) malloc( sizeof( Point ) );
▲ memcpy(pthis, p, sizeof( Point ) );
▲ pthis->dtor = FN_PTR(Point_dtor);
▲ pthis->print = FN_PTR(Point_print);
return pthis;
}
 
int Point_getX(Point* pthis) { return pthis->x; }
▲ int Point_getY(Point* pthis) { return pthis->y; }
▲ int Point_setX(Point* pthis, int x0) { pthis->x = x0; }
▲ int Point_setY(Point* pthis, int y0) { pthis->y = y0; }
▲ void Point_print() { printf("Point\n"); }
▲ void Point_dtor() {}
 
// Trick: This way Circle.x, Circle.y, Circle.r are available
typedef union Circle
{
Point point;▼
struct _Circle
{
Point point;
structint _Circler;
{};
} Circle;▼
▲ Point point;
▲ int r;
};
▲ } Circle;
 
 
Circle* Circle_new0()
{
Circle* pthis = (Circle*) malloc( sizeof( Circle ) );
memset(pthis, 0, sizeof( Circle ) );
pthis->dtor = FN_PTR(Circle_dtor);
pthis->print = FN_PTR(Circle_print);
}
 
Circle* Circle_new1(int x0)
{
Circle* pthis = (Circle*) malloc( sizeof( Circle ) );
pthis->x = x0;
pthis->y = 0;
pthis->r = 0;
pthis->dtor = FN_PTR(Circle_dtor);
pthis->print = FN_PTR(Circle_print);
}
 
Circle* Circle_new2(int x0, int y0)
{
Circle* pthis = (Circle*) malloc( sizeof( Circle ) );
pthis->x = x0;
pthis->y = y0;
pthis->r = 0;
pthis->dtor = FN_PTR(Circle_dtor);
pthis->print = FN_PTR(Circle_print);
}
 
Circle* Circle_new3(int x0, int y0, int r0)
{
Circle* pthis = (Circle*) malloc( sizeof( Circle ) );
pthis->x = x0;
pthis->y = y0;
pthis->r = r0;
pthis->dtor = FN_PTR(Circle_dtor);
pthis->print = FN_PTR(Circle_print);
}
 
Circle* Circle_newP0(Point* p)
{
Circle* pthis = (Circle*) malloc( sizeof( Circle ) );
pthis->x = p->x;
pthis->y = p->y;
pthis->r = 0;
pthis->dtor = FN_PTR(Circle_dtor);
pthis->print = FN_PTR(Circle_print);
}
 
Circle* Circle_newP1(Point* p, int r0)
{
Circle* pthis = (Circle*) malloc( sizeof( Circle ) );
pthis->x = p->x;
pthis->y = p->y;
pthis->r = r0;
pthis->dtor = FN_PTR(Circle_dtor);
pthis->print = FN_PTR(Circle_print);
}
 
void Circle_delete(Circle** pthis)
{
if(pthis && *pthis)
{
if(pthis && *pthis)->dtor();
▲ free(*pthis)->dtor(); *pthis = NULL;
{
(*pthis)->dtor();
free(*pthis); *pthis = NULL;
}
}
}
 
Circle* Circle_copy(Circle* c)
{
Circle* pthis = (Circle*) malloc( sizeof( Circle ) );
memcpy(pthis, c, sizeof( Circle ) );
pthis->dtor = FN_PTR(Circle_dtor);
pthis->print = FN_PTR(Circle_print);
return pthis;
}
 
int Circle_getX(Circle* pthis) { return pthis->x; }
int Circle_getY(Circle* pthis) { return pthis->y; }
int Circle_getR(Circle* pthis) { return pthis->r; }
int Circle_setX(Circle* pthis, int x0) { pthis->x = x0; }
int Circle_setY(Circle* pthis, int y0) { pthis->y = y0; }
int Circle_setR(Circle* pthis, int r0) { pthis->r = r0; }
void Circle_print() { printf("Circle\n"); }
void Circle_dtor() {}
 
int main()
{
Point* p = Point_new0();
Point* c = (Point*)Circle_new0();
p->print();
c->print();
return 0;
}</syntaxhighlight>
}
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