Re: Comma at end of enum lists

[Jacek Luczak <difrost.kernel@gmail.com>]

Mikael Pettersson pisze:
> Jacek Luczak writes:
>  > Hi All,
>  > 
>  > I've found that in many enum lists, there's a comma at the end, e.g. 
>  > (arch/x86/kernel/early_printk.c):
>  > 
>  > enum {
>  >          MAGIC1 = 0xBACCD00A,
>  >          MAGIC2 = 0xCA110000,
>  >          XOPEN = 5,
>  >          XWRITE = 4,
>  > };
>  > 
>  > Just out of curiosity, is there any particular reason here (no word in 
>  > CodingStyle about that).
> 
> Yes. This idiom allows you to add or remove items without
> changing adjacent lines.

Yep, that's obvious, one line less in diff after every enum change  :)

> In a language with strict a comma-as-separator rule you can
> get this benefit by placing the comma before new items rather
> than after existing items:
> 
> enum {	FOO
> 	,FIE
> 	,FUM
> };
> 
> but luckily C doesn't need this perversion.
> 

I was just curious, because it's not common schema (some miss extra comma).

Thanks,
	-Jacek