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Section: 17.9.7 [propagation] Status: Resolved Submitter: Daniel Krügler Opened: 2010-01-26 Last modified: 2016-01-28
Priority: Not Prioritized
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The current requirements for a conforming implementation of std::exception_ptr (17.9.7 [propagation]/1-6) does not clarify whether the expression
e1 != e2 e1 != nullptr
with e1 and e2 being two values of type std::exception_ptr are supported or not. Reason for this oddity is that the concept EqualityComparable does not provide operator !=.
For the same reason programmers working against the types X::pointer, X::const_pointer, X::void_pointer, and X::const_void_pointer of any allocator concept X (188.8.131.52 [allocator.requirements]/4 + Table 40) in a generic context can not rely on the availability of the != operation, which is rather unnatural and error-prone.
[ 2010 Pittsburgh: Moved to NAD Editorial. Rationale added below. ]
Solved by N3073.