Re: GOTO considered necessary (reworked)

[bobduff@world.std.com (Robert A Duff)]

In article <dewar.866851059@merv>, Robert Dewar <dewar@merv.cs.nyu.edu> wrote:
>Robert Duff says
>
><<I object to the term "fundamental" above.  I believe it is possible
>(though not easy) to implement controlled types with near-zero overhead
>on entering and leaving the scope of a controlled variable.>>
>
>First, you certainly can't eliminate the actual initializatoin and
>finalization (unless you are *very* clever indeed :-)

Of course.  That's not "overhead".  That's what the program want's to
do, and of course that code needs to get executed, in general.

>Second, eliminating the overhead from abort deferral if you are on top
>of an operating system is extremely complex.

Granted.  However, a program without aborts (or, without any tasking at
all) doesn't need that overhead.  That's what pragma Restrictions is
for.  I didn't say it's "easy" to eliminate this overhead -- I said it's
possible.

But the overhead I was thinking of was the overhead of automatically
putting controlled objects onto lists and taking them off, which is also
possible, but not easy, to eliminate.

- Bob