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Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;)

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Heikki Kallasjoki <fis+usenet@zem.fi> writes:

> On 2012-05-17, Heikki Kallasjoki <fis+usenet@zem.fi> wrote:
>> On 2012-05-17, Skybuck Flying <Windows7IsOK@DreamPC2006.com> wrote:
>>>>> private static void rangeCheck(int arrayLen, int fromIndex, int toIndex) 
>>>>> {
>>>>>     if (fromIndex > toIndex)
>>>>>         throw new IllegalArgumentException("fromIndex(" + fromIndex +
>>>>>                    ") > toIndex(" + toIndex+")");
>>>>>     if (fromIndex < 0)
>>>>>         throw new ArrayIndexOutOfBoundsException(fromIndex);
>>>>>     if (toIndex > arrayLen)
>>>>>         throw new ArrayIndexOutOfBoundsException(toIndex);
>>>>> }
>>>
>>> It's simply not valid. Out of bounds has a very clear meaning in programming 
>>> practice. It's either within bounds or it's not. The bounds of a java array 
>>
>> Yes, but it is not designed for testing whether fromIndex and toIndex
>> are within those bounds.  It is used to test whether fromIndex,
>> fromIndex+1, ..., toIndex-1 are, which it does.  In particular, the
>> element with index "toIndex" is not part of the range it's testing, so
>> it does not need to be inside the array bounds.
>
> For "proof", see the original comments that accompany the rangeCheck
> function:
>
> /**
>  * Checks that fromIndex and toIndex are in range, and throws an
>  * appropriate exception if they aren't.
>  *
>  * @param arrayLen the length of the array
>  * @param fromIndex the index of the first element of the range
>  * @param toIndex the index after the last element of the range
>  * @throws IllegalArgumentException if fromIndex > toIndex
>  * @throws ArrayIndexOutOfBoundsException if fromIndex < 0
>  *         or toIndex > arrayLen
>  */
>
> Note in particular the words "the index after the last element of the
> range".
>
> (Source:
> http://gee.cs.oswego.edu/cgi-bin/viewcvs.cgi/jsr166/src/main/java/util/TimSort.java?view=co
> )

This is in fact a good example of someone doing everything exactly
right: the JavaDoc provides a clear, unambiguous specification and the
code implements it exactly.  I can only wish all code were this "buggy".

-- 
Jim Janney

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Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-17 15:09 +0200
  Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Joshua Cranmer <Pidgeot18@verizon.invalid> - 2012-05-17 09:23 -0400
  Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-17 17:26 +0200
    Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Heikki Kallasjoki <fis+usenet@zem.fi> - 2012-05-17 16:19 +0000
      Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-17 19:57 +0200
        Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2012-05-17 18:33 +0000
          Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-17 23:25 +0200
            Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Lew <lewbloch@gmail.com> - 2012-05-17 14:52 -0700
            Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2012-05-17 14:58 -0700
            Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Joshua Cranmer <Pidgeot18@verizon.invalid> - 2012-05-17 17:59 -0400
              Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Heikki Kallasjoki <fis+usenet@zem.fi> - 2012-05-17 22:13 +0000
                Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-18 01:18 +0200
                Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Joshua Cranmer <Pidgeot18@verizon.invalid> - 2012-05-17 21:32 -0400
                Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Noob <root@127.0.0.1> - 2012-05-18 17:08 +0200
                Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-19 20:53 +0200
                Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-19 21:19 +0200
                Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2012-05-19 18:47 -0700
                Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-20 17:55 +0200
                Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-19 20:18 +0200
                Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-19 20:21 +0200
                Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-19 20:52 +0200
                Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Arne Vajhøj <arne@vajhoej.dk> - 2012-05-20 18:27 -0400
                Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Lew <noone@lewscanon.com> - 2012-05-19 14:48 -0700
                Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Lew <noone@lewscanon.com> - 2012-05-19 15:20 -0700
                Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Lew <noone@lewscanon.com> - 2012-05-19 15:35 -0700
                Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Arne Vajhøj <arne@vajhoej.dk> - 2012-05-20 18:25 -0400
                Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) bugbear <bugbear@trim_papermule.co.uk_trim> - 2012-05-21 17:12 +0100
                Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Heikki Kallasjoki <fis+usenet@zem.fi> - 2012-05-18 07:22 +0000
                Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Lew <noone@lewscanon.com> - 2012-05-19 14:50 -0700
                Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Arne Vajhøj <arne@vajhoej.dk> - 2012-05-20 18:21 -0400
                Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Arne Vajhøj <arne@vajhoej.dk> - 2012-05-20 18:23 -0400
              Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-18 01:09 +0200
            Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Arne Vajhøj <arne@vajhoej.dk> - 2012-05-20 18:14 -0400
              Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-21 09:36 +0200
          Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-20 17:53 +0200
            Re: names for parameters of ranges Arne Vajhøj <arne@vajhoej.dk> - 2012-05-20 18:30 -0400
              Re: names for parameters of ranges Gene Wirchenko <genew@ocis.net> - 2012-05-20 20:48 -0700
            Re: names for parameters of ranges (was: ...) Willem <willem@toad.stack.nl> - 2012-05-23 09:43 +0000
              Re: names for parameters of ranges Willem <willem@toad.stack.nl> - 2012-05-23 11:07 +0000
                Re: names for parameters of ranges Willem <willem@toad.stack.nl> - 2012-05-23 15:42 +0000
              Re: names for parameters of ranges Willem <willem@toad.stack.nl> - 2012-05-23 11:11 +0000
        Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Heikki Kallasjoki <fis+usenet@zem.fi> - 2012-05-17 19:13 +0000
          Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Heikki Kallasjoki <fis+usenet@zem.fi> - 2012-05-17 19:19 +0000
            Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Jim Janney <jjanney@shell.xmission.com> - 2012-05-17 18:35 -0600
          Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-17 23:16 +0200
            Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Arne Vajhøj <arne@vajhoej.dk> - 2012-05-20 18:32 -0400
              Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-21 09:40 +0200
                Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Joshua Cranmer <Pidgeot18@verizon.invalid> - 2012-05-21 10:05 -0400
    Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Arne Vajhøj <arne@vajhoej.dk> - 2012-05-20 14:41 -0400
    Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Arne Vajhøj <arne@vajhoej.dk> - 2012-05-20 18:12 -0400
      Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Keith Thompson <kst-u@mib.org> - 2012-05-20 16:38 -0700
        Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Lew <noone@lewscanon.com> - 2012-05-20 18:52 -0700
          Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Keith Thompson <kst-u@mib.org> - 2012-05-20 19:21 -0700
            Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) gazelle@shell.xmission.com (Kenny McCormack) - 2012-05-21 08:24 +0000
              Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Bill Leary" <Bill_Leary@msn.com> - 2012-05-23 14:34 -0400
          Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2012-05-20 21:46 -0600
            Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Lew <noone@lewscanon.com> - 2012-05-21 00:04 -0700
          Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) gazelle@shell.xmission.com (Kenny McCormack) - 2012-05-21 08:25 +0000
      Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-21 09:46 +0200
  Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) jacob navia <jacob@spamsink.net> - 2012-05-17 18:54 +0200
  Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Mark Storkamp <mstorkamp@yahoo.com> - 2012-05-17 12:06 -0500
    Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) markspace <-@.> - 2012-05-17 10:11 -0700
      Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Lew <lewbloch@gmail.com> - 2012-05-17 14:43 -0700
        Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) markspace <-@.> - 2012-05-17 16:13 -0700
          Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) markspace <-@.> - 2012-05-17 16:42 -0700
            Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Jan Burse <janburse@fastmail.fm> - 2012-05-18 02:27 +0200
      Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Arne Vajhøj <arne@vajhoej.dk> - 2012-05-20 15:06 -0400
  Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Marius" <sorry@nospamfor.me> - 2012-05-17 17:32 +0000
    Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-17 23:45 +0200
      Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Marius" <sorry@nospamfor.me> - 2012-05-17 22:16 +0000
        Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-18 00:47 +0200
          Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-24 14:11 +0200
            Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-24 14:17 +0200
  Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Roedy Green <see_website@mindprod.com.invalid> - 2012-05-18 02:57 -0700
    Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Leif Roar Moldskred <leifm@dimnakorr.com> - 2012-05-18 05:26 -0500
    Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Joshua Cranmer <Pidgeot18@verizon.invalid> - 2012-05-18 08:08 -0400
    Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Arne Vajhøj <arne@vajhoej.dk> - 2012-05-20 14:46 -0400
  Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) rossum <rossum48@coldmail.com> - 2012-05-18 12:25 +0100
    Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Gene Wirchenko <genew@ocis.net> - 2012-05-18 10:46 -0700
      Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-19 21:01 +0200
        Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Arne Vajhøj <arne@vajhoej.dk> - 2012-05-20 18:33 -0400
          Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Patricia Shanahan <pats@acm.org> - 2012-05-20 16:30 -0700
            Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Gene Wirchenko <genew@ocis.net> - 2012-05-20 20:36 -0700
              Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Kaz Kylheku <kaz@kylheku.com> - 2012-05-21 04:28 +0000
              Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-21 09:55 +0200
            Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-21 09:49 +0200
              Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Joshua Cranmer <Pidgeot18@verizon.invalid> - 2012-05-21 10:08 -0400
          Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-21 10:45 +0200
            Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-21 11:13 +0200
            Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-21 11:19 +0200
              Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Lew <lewbloch@gmail.com> - 2012-05-21 11:40 -0700
  Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Arne Vajhøj <arne@vajhoej.dk> - 2012-05-20 18:10 -0400
    Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-21 10:00 +0200
      Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Joshua Cranmer <Pidgeot18@verizon.invalid> - 2012-05-21 10:10 -0400
  Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) falk@rahul.net (Edward A. Falk) - 2012-05-23 05:40 +0000
    Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Jim Janney <jjanney@shell.xmission.com> - 2012-05-23 08:46 -0600
    Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) "Skybuck Flying" <Windows7IsOK@DreamPC2006.com> - 2012-05-24 14:03 +0200
      Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Lew <lewbloch@gmail.com> - 2012-05-24 09:56 -0700
      Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) falk@rahul.net (Edward A. Falk) - 2012-05-26 00:52 +0000
        Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Jamie <jamie_ka1lpa_not_valid_after_ka1lpa_@charter.net> - 2012-05-25 21:16 -0400
  Re: Oracle/Google demonstrate human beings cannot write 10 lines of code without making a mistake ;) Kevin McMurtrie <mcmurtrie@pixelmemory.us> - 2012-05-24 09:42 -0700

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