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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: Mon, 06 Apr 2026 12:02:25 -0700
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Bart <bc@freeuk.com> writes:

> On 15/03/2026 22:54, Tim Rentsch wrote:
>
>> 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++;
>>          }
>>      }
>
> Yes, but you'd prohibited many standard features including loops for
> your challenge.

I was responding to a context where the prohibitions had already
been violated.  I was simply pointing out that if those rules are
going to be ignored then there are easier ways to solve the problem
than importing exotic control structures from other languages.