Re: [Boost-users] C++ guru required!

Subject: Re: [Boost-users] C++ guru required!
From: Robert Ramey (ramey_at_[hidden])
Date: 2012-02-27 09:53:59

Sebastian Redl wrote:
> On 27.02.2012 07:15, Nevin Liber wrote:
>>
>> When you specify what you mean by "not checked by the compiler", then
>> we'll talk. :-)  Until you do, it is trivial to poke holes in it. For 
>> instance:
>>
>> if (0)
>> {
>>   Fire Fire Fire! (note: this line is NOT a C++ comment)
>>   if (ShouldTheIf0OnlyGoToTheFirstEndBraceItFinds())
>>   {
>>   }
>>   LaunchTheMissiles();
>>   if (0) {
>> }
>>
>> Did you really mean to launch the missiles?
>>
> That's not Robert's obligation to answer, since the original static if
> proposal leaves the details of this question open as well. (Note,
> though, that Andrei said that at the very least, the parser would have
> to ensure that the tokens are brace-balanced in the dead branch. There
> is no sane way to parse the example you've just given.)
>
> Robert's suggestion is just that "static if" can be replaced by "if"
> if the compiler is simply required to act as if the "if" was a
> "static if" if the condition is a constant expression.

Thanks for expressing this more clearly than I have.

> I think this is feasible. I also think it obscures intent, which is
> why I'm against it.

It's easy to express intent without adding anything to the language

/* static */ if ....

I'm concerned about adding stuff to the language syntax which
doesn't really add any functionality.  This makes the language
"bigger" to understand without making the functionality "bigger".

C++ is already way to hard to understand and I don't think
proposals like this don't reallly help.  What this is really about
is how to incorporate TMP functionality into the language in a way which
doesn't make the language unreadable.

OFF TOPIC

Seems many people are familiar with Andre's talk, I'm curious how many
here attended "GoingNative"
-in person
-via web broadcast

Robert Ramey

>
> Sebastian