Re: [9front] [PATCH] Fix assert macro to not break on commas

[ori@eigenstate.org]

Quoth Blue-Maned_Hawk <bluemanedhawk@gmail.com>:
> On 11/26/23 19:00, ori@eigenstate.org wrote:
> > Quoth Blue-Maned_Hawk <bluemanedhawk@gmail.com>:
> >> On 11/26/23 17:52, ori@eigenstate.org wrote:
> >>> Quoth Blue-Maned_Hawk <bluemanedhawk@gmail.com>:
> >>>> What reason have y'all for avoiding macros?
> >>>
> >>> Well, the fact that you need hacks like the one that started this
> >>> thread, for one;
> >>
> >> I don't see how it's a hack, but maybe i've just become numb to macro
> >> shenaniganry.
> >>
> >>>                   what if you had  macro that took *two* arguments?
> >>>
> >>> 	#define assert_msg(cond, msg) \
> >>> 		...what here?
> >>>
> >>> I don't see how you can avoid just saying "it's a macro, it's going
> >>> to be weird, don't even try".
> >>>
> >>
> >> Don't even try writing the macro or don't even try making it not weird?
> >> Because i can thing of a way to define such a thing:
> >>
> >> 	#define assert_msg(cond, msg) ((cond) ? (void)0 : (print(msg), exits(msg)))
> >>
> >> and i don't think that that's a particularly weird way to do so.
> > 
> > 
> > Wouldn't that fall apart on the same case that you showed above?
> > 
> > 	assert_msg((Thing){0, 1}.a, "foo");
> > 
> 
> Aye, correct you are.  In that case, it could be rearranged to
> 
> 	#define assert_msg(msg, ...) ((__VA_ARGS__) ? (void)0 : (print(msg), 
> exits(msg)))
> 
> and it would be able to tolerate unparenthesized commas in the checked 
> expression.


assert_msg((Thing){0, "foo"}.a, (Thing){1, "bar"}.b);