HELP with C++

[gopunk]

i'm pretty sure i know the answer, but i just wanted to be sure.

ap = new NonmovingObj(animPtr, new Disk(20, Green), 0, 0);
ap->update();

Disk is NOT a subclass of NonmovingObj.

both classes, NonmovingObj, and Disk have a function called update(). does the second line (through dynamic dispatching) call NonmovingObj's or Disk's update function?

i think it's Disk's but i'm not sure.

 

[Ameesh]

without seeing the code inside the functions i would say no, ap is a pointer to a NonmovingObj type it will call that class' update function.

 

[Ameesh]

a case where poly morphisim would come into play is when your update functions were declared virtual and Disk was derived from NonmovingObj and Disk didnt have an update function.

if you made a Disk obj and then called update is would call up the object to the next super class with a update function.

 

[gopunk]

hmm, yea pure, now that you put it that way, i see the logic in that.

ameesh, by "no", do you mean that it will NOT call Disk's function?

 

[gopunk]

thanks guys, appreciate it.

 

[Ameesh]

<< hmm, yea pure, now that you put it that way, i see the logic in that.

ameesh, by "no", do you mean that it will NOT call Disk's function? >>



correct, it will call Nonmoving obj's function