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From: Sergey Shandar (sergey_at_[hidden])
Date: 2007-11-28 19:09:37

shunsuke wrote:
> Sergey Shandar wrote:
>> 3. I found this one today:
>> template<class T>
>> operator T &() const
>> throw(typename ::boost::disable_if< ::boost::is_same<T, MyClass
>> const> >::type *)
> You've solved the millenium problem! :-)
> gcc3.4.5 and 4.1.2 seem to work fine.
> Thanks!
According to the standard, the code should not work.

    - All references in the function type of the function template to the
corresponding template parameters are replaced by the specified template
argument values. If a substitution in a template parameter or in the function
type of the function template results in an invalid type, type deduction fails.
[Note: *The equivalent substitution in exception specifications is done only
when the function is instantiated, at which point a program is ill-formed if
the substitution results in an invalid type.*] Type deduction may fail for the
following reasons:

However, it works on GCC. So, the workaround uses just another bug in
GCC :-)

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