operator==,!=,<,<=,>,>=(std::experimental::observer_ptr)

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template< class W1, class W2 >
bool operator==( const observer_ptr<W1>& p1, const observer_ptr<W2>& p2 );
(1) (library fundamentals TS v2)
template< class W1, class W2 >
bool operator!=( const observer_ptr<W1>& p1, const observer_ptr<W2>& p2 );
(2) (library fundamentals TS v2)
template< class W >
bool operator==( const observer_ptr<W>& p, std::nullptr_t ) noexcept;
(3) (library fundamentals TS v2)
template< class W >
bool operator==( std::nullptr_t, const observer_ptr<W>& p ) noexcept;
(4) (library fundamentals TS v2)
template< class W >
bool operator!=( const observer_ptr<W>& p, std::nullptr_t ) noexcept;
(5) (library fundamentals TS v2)
template< class W >
bool operator!=( std::nullptr_t, const observer_ptr<W>& p ) noexcept;
(6) (library fundamentals TS v2)
template< class W1, class W2 >
bool operator<( const observer_ptr<W1>& p1, const observer_ptr<W2>& p2 );
(7) (library fundamentals TS v2)
template< class W1, class W2 >
bool operator>( const observer_ptr<W1>& p1, const observer_ptr<W2>& p2 );
(8) (library fundamentals TS v2)
template< class W1, class W2 >
bool operator<=( const observer_ptr<W1>& p1, const observer_ptr<W2>& p2 );
(9) (library fundamentals TS v2)
template< class W1, class W2 >
bool operator>=( const observer_ptr<W1>& p1, const observer_ptr<W2>& p2 );
(10) (library fundamentals TS v2)

Compares the pointer values of two observer_ptrs, or a observer_ptr and nullptr.

1-2) Equality comparison for two observer_ptrs.
3-6) Equality comparison for an observer_ptr and nullptr.
7-10) Ordered comparison for two observer_ptrs.

Parameters

p, p1, p2 - observer_ptrs to compare

Return value

1) p1.get() == p2.get()
2) !(p1 == p2)
3-4) !p
5-6) (bool)p
7) std::less<W3>()(p1.get(), p2.get()), where W3 is the composite pointer type of W1* and W2*.
8) p2 < p1
9) !(p2 < p1)
10) !(p1 < p2)