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Elysia · 07-09-2009, 11:03 AM

Quote:

Originally Posted by Tux0r

When the values of them are the same then the destructor is called. The destructor will call an event. Like, creating a chest with treasure because the enemies were defeated. I believe it makes perfect sense, and because I'm using polymorphism I have to new (afaik).

You do not have to use new to use polymorphism.
All you need is a pointer or reference to the base class. Thus this will work:

Code:

Derived a;
Base* pa = &a;
pa->myfunction();
// Or
Base& ra = a;
ra.myfunction();

Furthermore, using delete this is something I would not recommend.
If you don't want to do manual deleting, then use smart pointers.

whiteflags · 07-09-2009, 11:26 AM

Well that's a crap way to demonstrate polymorphism, since that's not polymorphic at all.

Imagine two classes to represent the time, TwelveHourClock and TwentyFourHourClock, related through the abstract data type Time, which at minimum specifies for its children a timestamp method. One way to dump the time for all the Time types is through a polymorphic function.

Code:

void print (std::ostream& os, const Time& now) {
   os << "The time is " << now.timestamp() << '\n';
}

Elysia · 07-09-2009, 11:56 AM

Quote:

Originally Posted by whiteflags

Well that's a crap way to demonstrate polymorphism, since that's not polymorphic at all.

It was a way to demonstrate that you don't have to use new to use polymorphism.

whiteflags · 07-09-2009, 12:36 PM

But you didn't use polymorphism, so sorry if it's really my fault that you demonstrated so little.

Elysia · 07-09-2009, 12:38 PM

Alright, perhaps it was a bad example. I realize that now... I used a single class.
Well, I edited it to use Derived and Base to demonstrate that we're talking about polymorphism.

**Bubba** · 07-09-2009, 05:00 PM

Quote:

It will break broken usages of the facade pattern. There is nothing in the facade pattern that requires the facade to be a friend. Specifically, the facade pattern is not intended as a means of circumventing access control.

I was not indicating this was the case.

07-09-2009, 11:26 AM	#17
whiteflags Registered User Join Date: Apr 2006 Location: United States Posts: 3,201	Well that's a crap way to demonstrate polymorphism, since that's not polymorphic at all. Imagine two classes to represent the time, TwelveHourClock and TwentyFourHourClock, related through the abstract data type Time, which at minimum specifies for its children a timestamp method. One way to dump the time for all the Time types is through a polymorphic function. Code: void print (std::ostream& os, const Time& now) { os << "The time is " << now.timestamp() << '\n'; } __________________ Os iusti meditabitur sapientiam Et lingua eius loquetur indicium "There is nothing either good or bad, but thinking makes it so." (Shakespeare, Hamlet, Act II scene ii) http://www.myspace.com/whiteflags99
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07-09-2009, 12:36 PM	#19
whiteflags Registered User Join Date: Apr 2006 Location: United States Posts: 3,201	But you didn't use polymorphism, so sorry if it's really my fault that you demonstrated so little. __________________ Os iusti meditabitur sapientiam Et lingua eius loquetur indicium "There is nothing either good or bad, but thinking makes it so." (Shakespeare, Hamlet, Act II scene ii) http://www.myspace.com/whiteflags99
whiteflags is offline

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