Path: csiph.com!v102.xanadu-bbs.net!xanadu-bbs.net!feeder.erje.net!eu.feeder.erje.net!eternal-september.org!feeder.eternal-september.org!mx02.eternal-september.org!.POSTED!not-for-mail
From: Robbie Brown <rob@example.com>
Newsgroups: comp.lang.java.programmer
Subject: Re: ensuring unreachability
Date: Thu, 19 Feb 2015 09:48:07 +0000
Organization: A noiseless patient Spider
Lines: 56
Message-ID: <mc4bfg$t56$1@dont-email.me>
References: <slrnme63vm.uoi.avl@login.logic.tuwien.ac.at>	<statement-20150217115740@ram.dialup.fu-berlin.de>	<mc09k1$3se$1@dont-email.me>	<slrnme7nt2.uoi.avl@login.logic.tuwien.ac.at>	<mc2577$4vj$1@dont-email.me> <lvh9uj9tal.fsf@saunalahti.fi> <mc2ab7$p6q$1@dont-email.me> <mc2d1a$4r1$1@dont-email.me>
Mime-Version: 1.0
Content-Type: text/plain; charset=windows-1252; format=flowed
Content-Transfer-Encoding: 7bit
Injection-Date: Thu, 19 Feb 2015 09:47:28 +0000 (UTC)
Injection-Info: mx02.eternal-september.org; posting-host="896c419cace3c343dd1aaf493906dad2"; logging-data="29862"; mail-complaints-to="abuse@eternal-september.org";	posting-account="U2FsdGVkX19eWEC4yz2iAYQC3BBIaINrYGAs2axvAFE="
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:16.0) Gecko/20121010 Thunderbird/16.0.1
In-Reply-To: <mc2d1a$4r1$1@dont-email.me>
Cancel-Lock: sha1:GrccBRfsiIGRulY6idrxv6pU6Bs=
Xref: csiph.com comp.lang.java.programmer:31150

On 18/02/15 16:02, Jerry Stuckle wrote:
> On 2/18/2015 10:16 AM, Eric Sosman wrote:
>> On 2/18/2015 9:40 AM, Jukka Lahtinen wrote:
>>> Eric Sosman <esosman@comcast-dot-net.invalid> writes:
>>>
>>>>       Remember, the underlying purpose is to guard against a
>>>> maintainer who might inadvertently introduce a fall-through.
>>>
>>> Why not just insert the break; for every case?
>>> That's what it is for.
>>
>>      The original code was oddly structured:
>>
>>      case E1:
>>          if (...) {
>>             ...; return;
>>          } else if (...) {
>>             ...; throw ...;
>>          } else {
>>             ...; continue;
>>          }
>>      case E2:
>>          ...
>>
>> Inserting a `break' right before the E2 case would provoke a
>> compile-time error because the statement would be unreachable.
>>
>>      Andreas worries that someone might add a new alternative
>> to the `if' ladder, one that doesn't `return' or `throw' or
>> otherwise exit the `switch', thereby producing an unwanted
>> fall-through into E2.  I think the most straightforward way to
>> accomplish this is to eliminate the final `else' and brackets,
>> putting the `...; continue;' at the "top level" of the case.
>>
>
> I guess I have a different thought here.
>
> While it's nice to try to prevent a maintainer from doing this, it's a
> waste of time and effort.
>
> You need to give the maintainer some credit, also.  A maintainer has to
> be familiar enough with code that he/she can make the necessary changes.

...

Sanity at last. There is no way to prevent future foul ups unless the 
original author is present and remembers his state of mind at the time 
of writing (unlikely) or is capable of prescient preemptive time travel.

Alternatively you could always *comment* your code. I know, I know it's 
a subursive idea but it does work.

... but what if someone deletes the comments (jeez) :-)

-- 
Not floundering ... just fishing