Anonymous user
Polymorphism: Difference between revisions
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'''Libraries:''' Standard
/* After reading this you may understand */
/* why Bjarne Stroustrup's invented C++ */
#if defined( _WIN32 ) || defined( MSC_VER )
#define FN_PTR(x) (& x)
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int x;
int y;
void (*
void (*print)(); /* virtual */
} Point;
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Point* pthis = (Point*) malloc( sizeof( Point ) );
memset(pthis, 0, sizeof( Point ) );
pthis->dtor = FN_PTR(Point_dtor);
pthis->print = FN_PTR(Point_print);
}
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pthis->x = x0;
pthis->y = 0;
pthis->dtor = FN_PTR(Point_dtor);
pthis->print = FN_PTR(Point_print);
}
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pthis->x = x0;
pthis->y = y0;
pthis->dtor = FN_PTR(Point_dtor);
pthis->print = FN_PTR(Point_print);
}
void Point_delete(Point** pthis)
{
if(pthis && *pthis)
{
pthis->dtor();
free(*pthis); *pthis = NULL;
}
}
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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;
}
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int Point_setY(Point* pthis, int y0) { pthis->y = y0; }
void Point_print() { printf("Point\n"); }
void
// Trick: This way Circle.x, Circle.y, Circle.r are available
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Circle* pthis = (Circle*) malloc( sizeof( Circle ) );
memset(pthis, 0, sizeof( Circle ) );
pthis->dtor = FN_PTR(Circle_dtor);
pthis->print = FN_PTR(Circle_print);
}
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pthis->y = 0;
pthis->r = 0;
pthis->dtor = FN_PTR(Circle_dtor);
pthis->print = FN_PTR(Circle_print);
}
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pthis->y = y0;
pthis->r = 0;
pthis->dtor = FN_PTR(Circle_dtor);
pthis->print = FN_PTR(Circle_print);
}
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pthis->y = y0;
pthis->r = r0;
pthis->dtor = FN_PTR(Circle_dtor);
pthis->print = FN_PTR(Circle_print);
}
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pthis->y = p->y;
pthis->r = 0;
pthis->dtor = FN_PTR(Circle_dtor);
pthis->print = FN_PTR(Circle_print);
}
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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)
{
pthis->dtor();
free(*pthis); *pthis = NULL;
}
}
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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;
}
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int Circle_setR(Circle* pthis, int r0) { pthis->r = r0; }
void Circle_print() { printf("Circle\n"); }
void
int main()
{
Point* p = Point_new0();
Point* c = (Point*)Circle_new0();
p->print();
c->print();
return 0;
}
==[[C plus plus|C++]]==
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