WAY WAY WAY WAY OT Re: 'goto" gone from computer languages or is it!

[Vintage Computer Festival]

On Mon, 16 May 2005, Dave Dunfield wrote:

> >I trump thee collectively:
> >
> >void print_arg(int *aryp, size_t n)
> >{
> >
> >   char *t="%u,";
> >   int i=0;
> >
> >   for (;(i==n-1 ? t="%u" : i<n);) printf(t, *aryp + i++);
> >
> >   putchar('\n');
> >
> >}
> >
> >A little ugly (the compiler complains about the type mismatch in the unary
> >expression) but otherwise it works without caveats (that I know of ;)
> >
> >I suspect someone might bum it down further...no more precious time to
> >expend on this useless pursuit ;)
>
> I'm a little confused about the definition of "trump" when used in
> this case:
>
> - You have returned to an excess of local variables, and the
>   extra assignment - although you have used a (more expensive)
>   conditional to defer it until the last iteration.

There's one extra local variable (char *t) which is a pointer: hardly
expensive by any metric.  If you prefer, move the i initializer inside the
for loop construct.  Same difference.

> - You have returned to TWO conditionals, although you have
>   creatively moved them both into the for statement.

The loop uses the same number of conditionals as any other example so far
(including yours, which doesn't work ;)

> - In the last iteration of the loop you are stuffing the address
>   value of the constant string "%u" into the for conditional
>   (granted in any reasonable implementation this will be non-zero
>    and will evaluate to TRUE, however it seems a bit odd and not
>    completely necessary to the logic of the program).

Your analysis somewhat (misses the point|is non-sequitur).  The unary
construct is the entire reason this works.

> - You are reading only the first element of the array, although
>   you are adding an increasing offset to it for each iteration of
>   the loop.

Perhaps this is an issue of precedence and compiler implementation, but
the way it works (at least under gcc) is as I suspected, which is that
counter i gets incremented after first being added to aryp.  So it in fact
iterates the entire array from start to end.

> This really is getting silly.

Yes, but at least we're not talking about cars or guns.

> So... Seen any good old computers lately?

Thousands.

> How about them Altairs - ain't they something?

Over-rated.

> When I was a gaffer, we had to carry our card decks
> uphill both ways to the card punch!

You had card punches?  We had to cut holes into ours with exacto knives.

-- 

Sellam Ismail                                        Vintage Computer Festival
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