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digitalmars.D.learn - override keyword

reply Zarathustra <adam.chrapkowski gmail.com> writes:
When 'override' is so really required?
Nov 27 2008
parent "Steven Schveighoffer" <schveiguy yahoo.com> writes:
"Zarathustra" wrote
 When 'override' is so really required?

The grammar of your question is ambiguous, but I'll try to explain override. The override keyword *requires* that the function is an override of a base class' virtual function. Not using the override will still override the virtual function, but if you put override it will fail to compile if there is no virtual function to override. This isuseful, for example, if you are inheriting from a base class, and that base class changes the signature of a function that you chose to override, the compiler flags it as a failure. This way, you can see what was affected by the base class change. If you did not use the override keyword, then the code would still compile, but the new base class function would not be overridden, giving you potentially a disasterous silent bug. For this reason, many people have suggested requiring the override keyword to override virtual functions. But currently, it is still optional. Hope this helps. -Steve
Nov 27 2008