Re: Cannot understand the following codes

On 2006-03-29, Arthur J. O'Dwyer <ajonospam@xxxxxxxxxxxxxx> wrote:
On Wed, 29 Mar 2006, Ben C wrote:
[..] The difference between (*r) and (r) is that (*r) is the thing
pointed to by 'r', which is of function type, which, in this context,
immediately decays back to a function pointer. (r) is just that same
function pointer, without the dereference and decay. In other words,
(*r) decays to (r). Therefore, both expressions have the /exact same/
behavior.

I think more old code used the (*f)(x) style, and newer code, maybe
influenced by C++ and Lispy languages, uses plain old f(x) more often.
I tend to use (*cmp)(x,y) for callback functions in things like 'qsort',
but if I were writing something like

int (*printme)() = (widget == on)? magic: more_magic;

I'd use

printme(x);

instead.

Thanks. I tend to use (*f) just as a hint to the reader that it's an
indirect call.
.

Relevant Pages

  • Re: Cannot understand the following codes
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