https://gcc.gnu.org/bugzilla/show_bug.cgi?id=43943
Stefan <kdevel at vogtner dot de> changed:
What |Removed |Added
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CC| |kdevel at vogtner dot de
--- Comment #8 from Stefan <kdevel at vogtner dot de> ---
(In reply to Jonathan Wakely from comment #4)
> There are cases which are either not diagnosable or cannot be
> written, such as this example from Doug Gregor:
>
> in generic code, there might not be a way to create a value with the
> appropriate type. For example:
>
> template<typename T>
> T maybe_call(std::function<T(void)> f) {
> if (f)
> return f();
> else
> abort_program();
>
> // Cannot write a return here, because we have no way to
> create a value of type 'T'
> }
One can of course write a return there:
template<typename T>
T maybe_call(std::function<T(void)> f)
{
if (f)
return f();
else
abort_program();
// Cannot write a return here, because we have no way to create a value
of type 'T'
return f();
}
which refactors nicely into
template<typename T>
T maybe_call(std::function<T(void)> f)
{
if (! f)
abort_program();
return f();
}
