Ha. Nice work.

On 8/27/21 8:17 PM, Alejandro Colomar (man-pages) wrote:

Hi David,

On 8/28/21 2:01 AM, Alejandro Colomar (man-pages) wrote:

quoted

I mean:
!(int)x
(int)!x

The precedence doesn't matter there, as they apply one after the 
other, right to left.

So, I'll keep casts in row 2.

Hmm, I just came up with some very stupid piece of code that can show 
the different precedence between "unary operators" and "cast operators":

sizeof(int)x;

Which I hope no-one on earth would ever want to be valid C.

If casts had the same precedence as unary operators, this would be:
First, cast x to int, then apply sizeof to the resulting int (since 
sizeof can be used without parentheses on non-types).

But since sizeof has greater precedence than the cast, it would be:
First, calculate sizeof(int), then... x?  Invalid expression!

And luckily, the second thing happens, and the compiler yells:

sizeof.c: In function ‘foo’:
sizeof.c:3:20: error: expected ‘;’ before ‘x’
    3 |  return sizeof(int)x;
      |                    ^
      |                    ;


So I think this deserves a new row.

Thanks!

Alex

quoted

Cheers,

Alex

-- 
Have all good days!
David Sletten