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Section: 99 [func.ret] Status: C++11 Submitter: Jonathan Wakely Opened: 2008-09-10 Last modified: 2016-01-28
Priority: Not Prioritized
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Discussion:
The WP and TR1 have the same text regarding the argument types of a result_of expression:
The values ti are lvalues when the corresponding type Ti is a reference type, and rvalues otherwise.
I read this to mean that this compiles:
typedef int (*func)(int&); result_of<func(int&&)>::type i = 0;
even though this doesn't:
int f(int&); f( std::move(0) );
Should the text be updated to say "when Ti is an lvalue-reference type" or am I missing something?
I later came up with this self-contained example which won't compile, but I think it should:
struct X {
void operator()(int&);
int operator()(int&&);
} x;
std::result_of< X(int&&) >::type i = x(std::move(0));
[ Post Summit: ]
Recommend Tentatively Ready.
Proposed resolution:
Change 99 [func.ret], p1:
... The values ti are lvalues when the corresponding type Ti is an lvalue-reference type, and rvalues otherwise.