Re: No Go To's Forever!

[Robert Dewar <robert_dewar@my-deja.com>]

In article <0mVB4.193$2K6.17499@news.pacbell.net>,
  tmoran@bix.com wrote:

> How about:
>
> loop
>   look_ahead(in_file,ch,got_eol);
>   if got_eol then
>     skipline(infile);
>   elsif ch = ' '
>     get(infile, ch);
>   else
>     exit;
> end loop;


OK, but that is really changing the algorithm, which is not
always a satisfactory response. FOr example, if I offer the
following sorting algorithm:

  <<Do_It_Again>>
     for J in 1 .. N - 1 loop
        if D (J) < D (J + 1) then
           Swap (D (J), D (J + 1));
           goto Do_It_Again;
        end if;
     end loop;

then you could show me a (much more efficient) bubble sort
(which zips along at O(N**2) instead of the shorter algorithm
above which is O(N**3)) but that would not really speak to the
use of a goto in the above algorithm (I actually prefer the
above statement with a goto, which really in this case is just
a neat way of writing tail recursion) to the use of boolean
flags etc.

Of course you could argue that it is easier to find your refined
superior form from my syntactic expression with nested loops
than from the original with a goto, and that would be an
interesting argument to make.
>


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