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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups: comp.lang.c
Subject: Re: Sort of trivial code challenge - may be interesting to you anyway
Date: Sun, 15 Mar 2026 15:54:52 -0700
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Bart <bc@freeuk.com> writes:

> On 13/03/2026 11:58, Bart wrote:
>
> [characterizing my earlier code as a finite state machine]
>
>> Ideally it would just have a loop.  (In my languages, there is a
>> feature called 'doswitch',
>
> I ported this (C version using 'goto') to my scripting language just
> to see what it would look like:
>
>  https://github.com/sal55/langs/blob/master/tr.q
>
> This doesn't use 'goto', nor conventional loops.  However 'doswitch'
> does loop.
>
> An alternative method could use 'recase' (in C terms, jumping directly
> to a case label).  It's just goto 'under the hood', but much less
> underhand than 'longjmp'.
>
> Other ways of control flow include label pointers (also in some C
> extensions).

None of these more elaborate control structures are needed.  The
board display behavior can easily be expressed using conventional
control structures, in standard C:

    void
    show_board( unsigned height, unsigned width, unsigned cutoff ){
      const  int       D =  digits_width( cutoff );
      const  unsigned  R =  cutoff < height ? cutoff : height;
        unsigned   r = 0,   c = 0;

        while(  r < R  ){
            unsigned v = r + c*height;
            if(  v < cutoff    )  printf( " %*u", D, v+1 );
            if(  ++c >= width  )  putchar( '\n' ),  c = 0,  r++;
        }
    }