🚀 go-pugleaf

>>>>> "IW" ==   <ian> writes:
IW> Some recent comments in this newsgroup indicate that there is some
IW> problem with returning an auto_ptr from a function. I was not
IW> aware of this; the April 1995 working paper does not mention it
IW> and it is not obvious to me why there should be a problem other
IW> than the overhead of constructing and destroying a temporary
IW> object. Could somebody better informed than I am explain what the
IW> issue is? My apologies if this has been discussed before; I missed
IW> it.
[...]

AFAIK, the problem is not so much with returning an auto_ptr as
what can be done with the return value (not much). The signatures 
of the copy constructors and operator='s (which take non-const 
auto_ptr's) are incompatible with the rvalue character of function
return values.

Hence,

	auto_ptr<double> f();
	auto_ptr<double> p(f()); 	// Ah no, copy-ctor take 
					// non-const reference :(
and similarly:
	auto_ptr<double> p;
	p = f();	// Trouble again...

	Daveed
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