On 10/09/13 11:32, Jonathan M Davis wrote:
AFAIK, no official decision has ever been made. It seemed like Walter was
convinced that it was worth it to make non-virtual the default, and some
discussion went into how to do the transition, but I don't believe that Andrei
has ever liked the idea, and Walter never said that it was definitively
happening, much as he seemed to have been convinced that it should happen.
I seem to recall that the killer argument consisted of 2 parts:
* Having final-by-default means having speed by default. If people's
default experience is slower than C++, they will not hang around to
work out why or discover that speedups are possible.
* With final by default, a missing "virtual" on a method can be corrected
without breaking downstream code. By contrast, with virtual by default,
a missing "final" on a method (or whole class) can't be corrected without
a risk of downstream breakage.
The second was the one that really sold it to me.
