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Subject: Re: [boost] Is there interest in unit testing both passing and failing BOOST_MPL_ASSERTs?
From: Dave Abrahams (dave_at_[hidden])
Date: 2011-09-15 12:17:01

on Wed Sep 14 2011, Ben Robinson <> wrote:

>> Okay, let me see if I understand now: You want a way for the compiler to
>> ignore the static assertions and actually *try* to compile to errant code
>> to
>> ensure that you do, in fact, get a compiler error (which would normally be
>> caught early on by the static assertion). Is that right?
>> - Jeff
>> Yes. That is exactly it. :)
> One simple practical example I can give, is that in a library of mine, I
> have overloaded the free function operator+ for certain types of arguments.
> I then include the following in the function body:following:
> BOOST_MPL_ASSERT(sizof(T) == 0);

No you don't :-)

That shouldn't compile under any circumstances. BOOST_MPL_ASSERT takes
a parenthesized type, not an integral constant expression, as an

  BOOST_MPL_ASSERT((mpl::equal_to<int_<sizeof(T)>, int_<0> >))

might work.

Dave Abrahams
BoostPro Computing

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