Re: Use enum to declare errno values

From: Coywolf Qi Hunt
Date: Fri Dec 02 2005 - 07:57:21 EST


2005/12/2, Pekka Enberg <penberg@xxxxxxxxxxxxxx>:
> Hi,
>
> 2005/12/2, Denis Vlasenko <vda@xxxxxxxxxxxxx>:
> > > There is another reason why enums are better than #defines:
>
> On 12/2/05, Coywolf Qi Hunt <coywolf@xxxxxxxxx> wrote:
> > This is a reason why enums are worse than #defines.
> >
> > Unlike in other languages, C enum is not much useful in practices.
> > Maybe the designer wanted C to be as fancy as other languages? C
> > shouldn't have had enum imho. Anyway we don't have any strong motives
> > to switch to enums.
>
> I don't follow your reasoning. The naming collision is a real problem
> with macros. With enum and const, the compiler can do proper checking
> with meaningful error messages. Please explain why you think #define
> is better for Denis' example?
>
> Pekka
>

That is a bad bad style. It should be `#define FOO 123' if you have to
write it.

It's also hard to see what the confusing bar is "if you are looking at
file.c alone".

enum is worse than typdef. Don't you see why we should use `struct
task_struct', rather than `task_t'?

Introducing enum alone can't solve the problems from bad macro usage
habits. Actually, it's not anything wrong with macros, it's
programers' bad coding style.

Macros play an important role in C, but enums don't.
--
Coywolf Qi Hunt
http://sosdg.org/~coywolf/
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/