Smart pointer comparison - why a difference?

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From	Bo Persson<bop@gmb.dk>
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Subject	Smart pointer comparison - why a difference?
Date	Mon, 28 May 2012 14:53:04 -0700 (PDT)
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In C++11, operator<  for unique_ptr [unique.ptr.special] is defined as

std::less<CT>()(x.get(), y.get())

where CT is the common_type of the unique_ptr's internal pointer typedefs.


On the other hand, operator<  for shared_ptr [util.smartptr.shared.cmp]
is defined as

std::less<V>()(a.get(), b.get())

"where V is the composite pointer type (5.9) of T* and U*."


What exactly is the difference, and why?


Bo Persson


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Smart pointer comparison - why a difference? Bo Persson<bop@gmb.dk> - 2012-05-28 14:53 -0700
  Re: Smart pointer comparison - why a difference? Daniel Krügler<daniel.kruegler@googlemail.com> - 2012-05-29 11:25 -0700

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