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[dsimcha]

== Quote from Andrei Alexandrescu (SeeWebsiteForEmail at erdani.org)'s article
> On 9/29/10 10:43 PDT, Steven Schveighoffer wrote:
> > What I mean is, why is it automatically assumed that if front does not
> > return a ref, the only way to swap is via moveX? If T == int, why must
> > we have a moveFront to deal with it? IMO, all algorithms should default
> > to copying unless alternatives exist.
> Good point. We should arrange things such that all types without
> elaborate copy constructors allow swapping by copying.
> Could you please bugzillize this so it's not forgotten?
> Thanks,
> Andrei

This should already work (I noticed that it didn't a long time ago and checked in
the fix, but I don't remember how thoroughly I tested the fix).  Here's the
relevant snippet from std.algorithm:

 	void swapAt(R)(R r, size_t i1, size_t i2)
 	{
 	    static if (is(typeof(&r[i1])))
 	    {
 	        swap(r[i1], r[i2]);
 	    }
 	    else
 	    {
 	        if (i1 == i2) return;
 	        auto t1 = moveAt(r, i1);
 	        auto t2 = moveAt(r, i2);
 	        r[i2] = t1;
 	        r[i1] = t2;
 	    }
 	}

moveAt() simply copies if the range doesn't provide an explicit moveAt() and the
element type doesn't have an elaborate copy constructor.