Re: question about nullptr

On 2024-07-08, Michael S <already5chosen@yahoo.com> wrote:

On Sun, 07 Jul 2024 15:17:34 -0700
Keith Thompson <Keith.S.Thompson+u@gmail.com> wrote:
>

 
I just about always use NULL, not 0, when I want a null pointer
constant.  Similarly, I use '\0', not 0, when I want a null character,
0.0 when I want a floating-point zero, and false when I want a Boolean
zero.  I just like being explicit.
 

>
Pointer: I very rarely use NULL.
Character: I never use '\0'.
Floating point: I never use 0.0.

Never say never!

  printf("%f\n", 0);   // undefined behavior.
  printf("%f\n", 0.0); // correct

If you're #define-ing a floating-point constant that has
no fractional part, you should put that .0 there.

Someone's going to pass your constant as a variadic argument,
where it doesn't convert to floating-point.

Also:

  1/3   -> 0
  1/3.0 -> 0.33333...

If you're #define-ing a floating point constant that has
no fractional part, and don't include the .0, and the
programmer uses it as a division denominator thinking that
it's a floating-point quantity, oops!

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