On Thu, Jun 7, 2012 at 6:50 PM, Minas <minas_mina1990@hotmail.co.uk> wrote:

I agree that the default value for floats/doubles should be zero. It feels much more natural.

The point is to make sure code is correct. Initializing your variables should be what feels natural. Leaving then uninitialized is bad style, bad practice, and generally a bad idea. If getting stung by a float initializing to NaN is what it takes to make that happen, so be it.

I think the problem here is that people are thinking about some stuff too much. D is a rather new language that wants to be practical. Floats defaulting to NaN is NOT practical FOR MOST PEOPLE when at the same time I write:

Actually, as far as I know, floats have been initialized to NaN since D first appeared in 2001. This isn't news.

int sum;

for(...)
sum += blah blah blah

And it works.

In any other systems language, this would be undefined behavior. D is simply trying to make initialization bugs as obvious as possible. With ints, the best we can do is 0. With floats, NaN makes it better.