Re: [basic-improvements] try/finally support for c/c++ - more tests

[Fergus Henderson <fjh@cs.mu.OZ.AU>]

On 07-Nov-2002, Fergus Henderson <fjh@cs.mu.OZ.AU> wrote:
> On 06-Nov-2002, Richard Henderson <rth@redhat.com> wrote:
> > The main problem is that you simply cannot implement cleanups with
> > a few calls to a runtime library.
> 
> This is not true.  Cleanups *can* be implemented via a runtime library.
> It's just that you need to use callbacks, and this makes the code
> harder to read and less efficient.

Actually, if you use GNU C nested functions, it's only very slightly harder
to read: instead of

	void foo() {
		__try {
			do_some_stuff();
		}
		__finally {
			do_some_cleanup();
		}
	}

you have

	void foo() {
		void stuff(void) {
			do_some_stuff();
		}
		void cleanup(void) {
			do_some_cleanup();
		}
		try_finally(stuff, cleanup);
	}

Anyway my guess is that glibc would probably end up using macros for this,

	void foo() {
		TRY_FINALLY({
			do_some_stuff();
		},{
			do_some_cleanup();
		})
	}

and the important thing is the readability of the code using the macro,
not the readability of the code which defines the macro.  So in that case,
it's just an efficiency issue.

-- 
Fergus Henderson <fjh@cs.mu.oz.au>  |  "I have always known that the pursuit
The University of Melbourne         |  of excellence is a lethal habit"
WWW: <http://www.cs.mu.oz.au/~fjh>  |     -- the last words of T. S. Garp.