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Re: Some changes to autoconfiguration APIs



At Fri, 30 Apr 2021 23:05:48 -0400 (EDT), Mouse <mouse%Rodents-Montreal.ORG@localhost> wrote:
Subject: Re: Some changes to autoconfiguration APIs
>
>   However, I see little reason to do the
> statement expression rather than
>
> 	{ static const struct cfargs foo = { ... };
> 	  config_found(..., &foo);
> 	}

That's a very good point!

I think statement expressions can be a rather "dangerous" complication
in C -- I've only ever found them to be truly useful within a macro when
I'm trying to avoid, or do something different than, the "usual
promotions".


Kind of related to this, I have the following comment in my notes about C:

- Positional parameters are evil (or at least error prone), especially
  for variable numbers of parameters.

Named parameters can be simulated in modern C with full structure
passing:


	struct fooness {
		int blah;
	};
	struct somefunc_params {
		char *p1;
		int i1;
		struct fooness foo;
	};
	int
	somefunc(struct somefunc_params p)
	{
		if (p.i1)
			printf("%s", p.p1);
		return 0;
	}

	res = somefunc((struct somefunc_params)
		       {.p1 = "foo",
		        .i1 = 1,
		        .foo = (struct fooness) {.blah = 4}});

A working example with more rants and ravings about C, and some other
ideas about hiding the struct references within the function
implementation is here:

	https://github.com/robohack/experiments/blob/master/tc99namedparams.c

--
					Greg A. Woods <gwoods%acm.org@localhost>

Kelowna, BC     +1 250 762-7675           RoboHack <woods%robohack.ca@localhost>
Planix, Inc. <woods%planix.com@localhost>     Avoncote Farms <woods%avoncote.ca@localhost>

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