🚀 go-pugleaf

b91926@fsgm01.fnal.gov (David Sachs) writes:
	...
>easy to produce a case in which X x(a); and X x=a; behave differently,
>where a is a class object, of a class that has a conversion operator to
>X&, and another higher priority conversion to something accepted by a
>constructor of class X. then:
>X x(a) uses higher priority conversion by overloading rules
>X x=a uses X(a.operator X&)

I think I'm confused here -- what would be a "higher priority conversion"
from a class object a to something accepted by a constructor of class X,
than an operatorX&() member of a's class (call that class A)...?

It seems to me that the highest priority conversion of them all would
be "no conversion at all", i.e. assume class X has a constructor that
accepts an A, as in...:

class X:
class A{ public: operatorX&() const; };
class X{ public: X(const A&); X(const X&); }

Even in this case, wouldn't the two usages...:

    A a;
    X x1(a);
    X x2=a;

just both be _ambiguous_...?  I do suspect I may be somewhat
confused here, so would appreciate clarification (ideally with
draft standard chapter&verse reference, thanks!).


Alex
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