I was trying to break some polymorphism, expecting it not to work, but I'm a
curious sort.
I was seeing what happens when a derived class tries to hide an inherited
method with a private new method, expecting an error or warning; I got
neither with the result that the inherited method does _not_ get hidden (i.e.
not possibe to break polymorphism/inheritance this way, yay!)
My question then is, why is there no warning that the code may not work the
way the writer expects? Is it simply because the _new_ keyword turns it off?
Without the _new_ keyword, the warning about hiding fires, but this is a case
where no hiding will happen anyway, because the private method _does_not_
hide the inherited method.
5  2118 
PIEBALD <PI*****@discus sions.microsoft .com> wrote: I was trying to break some polymorphism, expecting it not to work, but I'm a
curious sort.
I was seeing what happens when a derived class tries to hide an inherited
method with a private new method, expecting an error or warning; I got
neither with the result that the inherited method does _not_ get hidden (i.e.
not possibe to break polymorphism/inheritance this way, yay!)
My question then is, why is there no warning that the code may not work the
way the writer expects? Is it simply because the _new_ keyword turns it off?
Without the _new_ keyword, the warning about hiding fires, but this is a case
where no hiding will happen anyway, because the private method _does_not_
hide the inherited method.
Well, it hides it within that class - it just doesn't hide it for other
users of the class.
--
Jon Skeet - <sk***@pobox.co m> http://www.pobox.com/~skeet Blog: http://www.msmvps.com/jon.skeet
If replying to the group, please do not mail me too
And, by casting the derived object to the base class, I can even call
the "hidden" method!
Bob
"Jon Skeet [C# MVP]" <sk***@pobox.co m> wrote in message
news:MP******** *************** *@msnews.micros oft.com... PIEBALD <PI*****@discus sions.microsoft .com> wrote: I was trying to break some polymorphism, expecting it not to work, but
I'm a
curious sort.
I was seeing what happens when a derived class tries to hide an inherited
method with a private new method, expecting an error or warning; I got
neither with the result that the inherited method does _not_ get hidden
(i.e.
not possibe to break polymorphism/inheritance this way, yay!)
My question then is, why is there no warning that the code may not work
the
way the writer expects? Is it simply because the _new_ keyword turns it
off?
Without the _new_ keyword, the warning about hiding fires, but this is a
case
where no hiding will happen anyway, because the private method _does_not_
hide the inherited method.
Well, it hides it within that class - it just doesn't hide it for other
users of the class.
--
Jon Skeet - <sk***@pobox.co m>
http://www.pobox.com/~skeet Blog: http://www.msmvps.com/jon.skeet
If replying to the group, please do not mail me too
Bob Milton <Do********@new sgroup.nospam> wrote: And, by casting the derived object to the base class, I can even call
the "hidden" method!
Absolutely - but that's always true with "hiding", as anything else
would break Liskov's Substitution Principle.
--
Jon Skeet - <sk***@pobox.co m> http://www.pobox.com/~skeet Blog: http://www.msmvps.com/jon.skeet
If replying to the group, please do not mail me too
True. But it still amazes me how many people want to be able to
eliminate a public function in the base class (which in essence you can't
really do).
Bob
"Jon Skeet [C# MVP]" <sk***@pobox.co m> wrote in message
news:MP******** *************** *@msnews.micros oft.com... Bob Milton <Do********@new sgroup.nospam> wrote: And, by casting the derived object to the base class, I can even call
the "hidden" method!
Absolutely - but that's always true with "hiding", as anything else
would break Liskov's Substitution Principle.
--
Jon Skeet - <sk***@pobox.co m>
http://www.pobox.com/~skeet Blog: http://www.msmvps.com/jon.skeet
If replying to the group, please do not mail me too This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
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