• Ender KaShae <astrothayne gmail.com> Aug 06 2007

Ender KaShae <astrothayne gmail.com> writes:

kris Wrote:

 Walter:
 
 There's a related problem where a public method is added to a base-class 
 A (as in your example) but where the signature is *exactly* that of one 
 existing in derived class B. If A actually calls that new method 
 internally, "bad things"tm will almost certainly happen, since B never 
 intended to effectively override the newly-added method in A.
 
 This is a very hard problem to isolate yet can be easily remedied by the 
 compiler. The request was first made two or three years back, and once 
 or twice since then: you make the "override" keyword *required*.
 
 When "override" is required, the compiler can easily trap this related 
 type of hijacking and avoid such nasty surprises.
 


if the function is overrided ONLY when the override keyword is there would
prevent prevent any errors when such an action occurrs, but you also run into
the bittersweet situation of hiding members of the base class.