Subject: Re: [boost] [locale] Review part 1: headers
From: Artyom (artyomtnk_at_[hidden])
Date: 2011-04-10 00:18:43
> >>>> line 646: Normally it's undefined behavior to
> >>>> dereference an iterator like this. I would
> >>>> prefer an assert to throwing an exception.
> >>> The point is that these locations are valid
> >>> positions just you can't call operator*.
> >>> I think it is better behavior because it
> >>> is quite easy to make a mistake with this.
> >>> (From my experience with this)
> >> Of course, it's a good thing to detect
> >> the error. The thing is that an exception
> >> means that you unwind the stack, possibly
> >> handling the exception at a higher level.
> >> That's normally not the correct response
> >> for a programming error.
> > It is similar to std::vector's at()...
> > Maybe, in any case I had found exception helpful,
> > especially in situation when you don't a error in some part
> > to shutdown entire process.
> > Defensive but forgiving programming.
> Definitely a no-no.
> Dereferencing an invalid iterator is a programming error, not an
> exceptional situation.
> The thing to use is an assertion.
> When your code is statically wrong, the compiler refuses to generate a
> binary. Likewise, when your code is dynamically wrong, it just terminates.
> Fix your code such that such situations may *never* happen. An exception
> is something that *could* happen, even in bug-free software, like a
> failure to perform an operation due to lack of the necessary resources.
I'm sorry but as far as I remember nobody deprecated
std::logic_error (and std::out_of_range derived from it).
Small point, when you program some mission critical systems
and services you don't want the process to go down for
something that maybe only a single response can go
down that way. This is very important for some
mission critical code (and I had written such
code not once).
In any case, this concept is part of C++03 and C++0x
and can be seen via std::logical_error that allows
to catch programmers errors.
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