C++: difference between 0. and 0.0?

Question

I am well aware of the difference between 0 and 0.0 (int and double).

But is there any difference between 0. and 0.0 ( please note the . )?

Thanks a lot in advance,

Axel

Answer 1

There is no difference. Both literals are double. From the C++-Grammar:

fractional-constant:
    digit-sequenceopt . digit-sequence
    digit-sequence .

See: Hyperlinked C++ BNF Grammar