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From: Peter Dimov (pdimov_at_[hidden])
Date: 2001-05-24 09:01:41
I have some comments on shared_ptr.
1. Isn't specializing std::less without defining the corresponding operator<
setting a dangerous precedent? This means that sort(f, l) and sort(f, l,
less<>()) could potentially give different results.
2. I need to access shared_ptr::pn. Really.
Consider this case:
shared_ptr<A> pa;
shared_ptr<B> pb;
Do pa and pb point to the same object? No way to tell without comparing
pa.pn and pb.pn.
Why does this matter? Suppose that I have a persistence library and I want
to 'persist' shared_ptr's. I'm given a shared_ptr<X> that has an use_count()
of 2. Has the object already been written to disk? A set of pn's would
answer this question easily, but without access to shared_ptr::pn, I can't
build this set.
-- Peter Dimov Multi Media Ltd.