Re: Defect Report: Unintended consequences of N2351
On Aug 19, 3:04 am, AlbertoBarb...@libero.it (Alberto Ganesh Barbati)
wrote:
These two example alone are sufficient, IMHO, to motivate the "new"
constructor. However, I still can't find an example that can motivate
having an empty shared_ptr with a non-null stored pointer...
An empty shared_ptr is almost as efficient as a raw pointer; it
doesn't allocate on construction, and it doesn't maintain a reference
count on copy/destroy. This is what makes it useful in certain
scenarios and circles. :-)
The aliasing constructor is already sharp enough to cut through limbs,
so its uses should be screened carefully and there isn't much safety
to be gained by specifically testing for this situation in the
constructor and doing something to prevent it.
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