Re: kernel.h: add ARRAY_AND_SIZE() macro to complement ARRAY_SIZE().

[Christer Weinigel <christer@weinigel.se>]

Alexey Dobriyan wrote:
> On Fri, Sep 19, 2008 at 08:28:45AM -0700, Russ Dill wrote:
>> My vote is for ARRAY_AND_SIZE to spread far and wide across the land.
>> ARRAY_SIZE is already very safe, as it has a __must_be_array macro
>> built in. So ARRAY_AND_SIZE is even safer, as it prevents you from
>> mixing up two different arrays. It also reduces line length and makes
>> driver and device (usually platform_device) registration code easier
>> to read.
> 
> It also spreads ARRAY_SIZE misnaming futher.

You still haven't explained what's misnamed about it, nor suggested a 
better name.

> It introduces one more core macro and quite pointless one. I can't
> personally recall a single bug where sizeof() was taken from another
> array.

You haven't written a lot of machine definitions then.  When adding 
platform devices for an embedded platform one has to write a lot of 
boilerplate like this:

     platform_add_devices(n30_devices, ARRAY_SIZE(n30_devices));

and it is much too easy to copy paste that line and miss one of the 
references.

> It creates interesting confusion point: ARRAY_AND_SIZE is about array
> and it's size. What ARRAY_SIZE is about then?

ARRAY_AND_SIZE -> (An) array and (its) size

ARRAY_SIZE -> (The) array size

Sure, you could write ARRAY_AND_ITS_SIZE, but would that really make 
anyone happy?  Cobol went out of fashion a long time ago.

   /Christer