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Re: Minimum amount of syntax for C language

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On 17/11/2016 18:58, Jerry Stuckle wrote:
> On 11/17/2016 12:03 PM, John Bode wrote:
>> On Wednesday, November 16, 2016 at 10:22:23 AM UTC-6, Osmium wrote:
>>> "Mr. Man-wai Chang" wrote:
>>>
>>>> For teaching purposes, do you need complete and full C syntax? DO you need
>>>> a sophiscated compiler?
>>>
>>> On further thought, I can't think of any situation where the goto
>>> statement is required.
>>
>> Not *required*, but one place where it is useful (and not immediately a
>> sign of poor design or practice) is bailing out of a deeply nested loop
>> or multi-step resource allocation process:
>>
>>     for ( ... )
>>       for ( ... )
>>         for ( ... )
>>           if ( some_error )
>>             goto exit:
>>
>>     exit: // clean up
>>
>> Obviously, you'll want to structure your code such that you avoid that
>> situation, but sometimes it simply isn't possible (or, the level of
>> effort required to do so is not worth the tradeoff).
>>
>
> Or,
>
>    bool exit = false;
>    for (... && !exit)
>       for (... && !exit)
> 	 for (... && !exit)
>             if (some_error) {
> 	        exit = true;
>                 break;
>             }
>
> Clean easy to understand and no goto.

But it won't do the same thing. Suppose there is extra code after each loop:

      for ( ... ) {
        for ( ... ) {
          for ( ... ) {
            if ( some_error )
              goto exit:
          }
          A;
        }
        B;
      }
      C;
// clean up ...

With your scheme, A and B will still be executed before it quits the 
outer loop, and C will be executed on exit from the outer loop.

Apart from which you don't your code cluttered up with all this extra logic.

-- 
Bartc

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Thread

Minimum amount of syntax for C language "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-11-13 18:56 +0800
  Re: Minimum amount of syntax for C language BartC <bc@freeuk.com> - 2016-11-13 11:26 +0000
    [OT] "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-11-13 19:41 +0800
      Re: [OT] BartC <bc@freeuk.com> - 2016-11-13 12:42 +0000
        Minimum amount of syntax for C language "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-11-13 20:45 +0800
          Re: Minimum amount of syntax for C language jameskuyper@verizon.net - 2016-11-13 07:42 -0800
            Re: Minimum amount of syntax for C language "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-11-14 00:01 +0800
              Re: Minimum amount of syntax for C language jameskuyper@verizon.net - 2016-11-13 10:00 -0800
              Re: Minimum amount of syntax for C language "Osmium" <r124c4u102@comcast.net> - 2016-11-13 13:16 -0600
                Re: Minimum amount of syntax for C language BartC <bc@freeuk.com> - 2016-11-13 19:28 +0000
                Re: Minimum amount of syntax for C language Thiago Adams <thiago.adams@gmail.com> - 2016-11-14 08:10 -0800
              Re: Minimum amount of syntax for C language John Bode <jfbode1029@gmail.com> - 2016-11-14 12:34 -0800
              Re: Minimum amount of syntax for C language "Osmium" <r124c4u102@comcast.net> - 2016-11-16 10:22 -0600
                Re: Minimum amount of syntax for C language supercat@casperkitty.com - 2016-11-16 08:33 -0800
                Re: Minimum amount of syntax for C language "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-11-17 22:11 +0800
                Re: Minimum amount of syntax for C language BartC <bc@freeuk.com> - 2016-11-17 16:30 +0000
                Re: Minimum amount of syntax for C language "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-11-18 01:05 +0800
                Re: Minimum amount of syntax for C language John Bode <jfbode1029@gmail.com> - 2016-11-17 09:03 -0800
                Re: Minimum amount of syntax for C language Jerry Stuckle <jstucklex@attglobal.net> - 2016-11-17 13:58 -0500
                Re: Minimum amount of syntax for C language BartC <bc@freeuk.com> - 2016-11-17 19:10 +0000
                Re: Minimum amount of syntax for C language Jerry Stuckle <jstucklex@attglobal.net> - 2016-11-17 17:41 -0500
                Re: Minimum amount of syntax for C language Thiago Adams <thiago.adams@gmail.com> - 2016-11-17 11:03 -0800
                Re: Minimum amount of syntax for C language Keith Thompson <kst-u@mib.org> - 2016-11-17 11:56 -0800
                Re: Minimum amount of syntax for C language "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2016-11-17 12:17 -0800
                Re: Minimum amount of syntax for C language Thiago Adams <thiago.adams@gmail.com> - 2016-11-17 12:21 -0800

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