checkedint call removal

[Andrei Alexandrescu via Digitalmars-d]

On 8/1/14, 9:46 PM, Chris Cain wrote:
> On Saturday, 2 August 2014 at 04:28:33 UTC, Timon Gehr wrote:
>> On 08/02/2014 06:11 AM, Chris Cain wrote:
>>> On Saturday, 2 August 2014 at 03:40:47 UTC, Timon Gehr wrote:
>>>> I already googled 'statement of fact' myself earlier, and found the
>>>> wikipedia entry for 'fact', that I quoted back then:
>>>> http://en.wikipedia.org/wiki/Fact
>>>>
>>>> "The usual test for a statement of fact is verifiability, that is,
>>>> whether it can be demonstrated to correspond to experience."
>>>>
>>>> I.e. in order to determine whether something is a statement of fact,
>>>> one should verify it. Do you agree that it is saying this?
>>>
>>> I'll just do this real quick, because it's a really easy one to show the
>>> problem with.
>>>
>>> Google "verifiable" ->
>>> http://www.merriam-webster.com/dictionary/verifiable -> "capable of
>>> being verified"
>>> ...
>>
>> Great, now we are getting somewhere.
>>
>> http://dictionary.reference.com/browse/verify?s=t
>>
>> "to prove the truth of, as by evidence or testimony; confirm;
>> substantiate: Events verified his prediction."
>>
>> I understand "capable of being verified" as "there is a way to verify
>> this" which is the same as "this can be proven" which would imply
>> "this is true".
>>
>> What's wrong here?
>
> The fact that you assume that something "can be proven" means it "has
> been proven" or "must be proven". Because you don't necessarily have to
> prove it, it doesn't necessarily mean it is true. It's a statement that
> you are suggesting is true but *could* be falsified/shown to be
> false/verified/verified to be false.
>
> The mere fact that asserts take in expressions show that something "can
> be proven", but there is no implication that it, therefore, must be
> proven. If you put an expression in an assert and it successfully
> compiles, you've made a statement of fact. It's useful that it is
> checked/proven in debug builds but not surprising that it's required to
> by definition.
>
>>
>>> That is, it's something that has some ability to be verified. Thus, 1==2
>>> is "verifiable" (it can be shown to be either true or false).
>>> ...
>>
>> If I can verify 1==2, I would prove 1==2, as per the definition above,
>> no?
>
> No. You can verify it but find it to be false. Your proof would show it
> to be false. The fact that you can write a proof showing it to be false
> is a proof that it was verifiable in the first place.
>
>> It is possible that this is indeed what it tries to communicate.
>> Thanks for bearing with me in any case!
>
> No problem. :)
>
>> But as I wrote in my previous post, now this brings up the issue that
>> if an assertion is a statement of fact, then it is not necessarily true.
>>
>> Why is it now obvious that it should be considered true?
>
> For the same reason that all of the other things you type into a program
> is accepted by a program.
>
> `if(...)` ... would it be strange if your program doubted that you
> really want to execute the block the if statement refers to? Of course
> it would.
>
> Basically, you're a god and what you say to do is law in computer
> programming. By default you expect the computer to not doubt you and to
> follow what you say. It's not like a person who will question your
> assertions and ask you to prove them or double check them for you.
>
> Though, the fact that it will double check them for you is helpful in
> debug builds, so it's an obvious enhancement for debugging purposes.
>
> Since assert is you making a statement of fact, it's logical that it
> should, by default, accept what you say just like it accepts every other
> command you give it.
>
> If you're wrong... well, it's just like if you're wrong about your if
> statements or if you call the wrong function or pass in the wrong
> variables. You'll get incorrect program behavior. Unlike those other
> things, since it's verifiable, there exists some sort of configurations
> where the program can be helpful to you by verifying your assertions.

I don't think there's ever been a more majestic thread in the history of 
this forum. Probably up there with the best of them anywhere and 
anytime. It's become officially an Epic Debate.

Andrei