Re: Emacs rewrite in a maintainable language

[Oleh Krehel <ohwoeowho@gmail.com>]

Paul Eggert <eggert@cs.ucla.edu> writes:

> On 10/12/2015 08:17 AM, Oleh Krehel wrote:
>> Quoting the Emacs sources:
>>
>>      # define MIN(a,b) ((a) < (b) ? (a) : (b))
>>      #define streq(X, Y) (*(X) == *(Y) && strcmp ((X) + 1, (Y) + 1) == 0)
>>      #define SET_FLAG(F, FLAG)	((F) |= (FLAG))
>>      #define HAS_FLAG(F, FLAG)	(((F) & (FLAG)) != 0)
>>      #define xnew(n, Type)      ((Type *) xmalloc ((n) * sizeof (Type)))
>>      #define xrnew(op, n, Type) ((op) = (Type *) xrealloc (op, (n) * sizeof (Type)))
>>      #define switch_line_buffers() (curndx = 1 - curndx)
>>      #define curlinepos (lbs[curndx].linepos)
>>      #define BVAR(buf, field) ((buf)->field ## _)
>>
>> Some of these can be replaced with plain type checked C++
>
> Only BVAR belongs to the Emacs core. The other macros belong to
> auxiliary executables that presumably would be unaffected by any
> rewrite of the core. Anyway, for fun I just now replaced streq,
> SET_FLAG, and HAS_FLAG with functions, in the attached patch. More
> work needs to be done in this area but one step at a time....

Thanks, Paul.

May I ask if there's a reason to not have a single style for const
pointers? I get 2162 occurrences of "const char *", and 357 occurrences
of "char const *" in the C sources.

I have to admit that I haven't seen the "char const *" variation
anywhere before. Just to get another sample, I looked at the Linux
sources; their ratio is 31961:189 in favor of "const char *".

If no one deems it counter-productive, I'd like to switch all const
pointers to a single "const char *" style. If we want more people to be
comfortable with the C sources, style and consistency is important.

    Oleh