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    CWG Issue 1237</TITLE>
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<P><EM>This is an unofficial snapshot of the ISO/IEC JTC1 SC22 WG21
  Core Issues List revision 118b.
  See http://www.open-std.org/jtc1/sc22/wg21/ for the official
  list.</EM></P>
<P>2025-09-28</P>
<HR>
<A NAME="1237"></A><H4>1237.
  
Deprecated implicit copy assignment in example
</H4>
<B>Section: </B>6.8.7&#160; [<A href="https://wg21.link/class.temporary">class.temporary</A>]
 &#160;&#160;&#160;

 <B>Status: </B>C++11
 &#160;&#160;&#160;

 <B>Submitter: </B>Ryou Ezoe
 &#160;&#160;&#160;

 <B>Date: </B>2011-01-25<BR>


<P>[Voted into the WP at the March, 2011 meeting as part of paper N3262.]</P>

<P>An implicit declaration of a copy assignment operator is deprecated
if the class has a user-declared copy constructor or a user-declared
destructor.  However, the example in 6.8.7 [<A href="https://wg21.link/class.temporary">class.temporary</A>] relies
on such an implicit declaration; an explicit declaration for the copy
assignment operator for class X should be provided:</P>

<PRE>
    class X {
    public:
      X(int);
      X(const X&amp;);
      ~X();
    };

    class Y {
    public:
      Y(int);
      Y(Y&amp;&amp;);
      ~Y();
    };

    X f(X);
    Y g(Y);

    void h() {
      X a(1);
      X b = f(X(2));
      Y c = g(Y(3));
      a = f(a);  //<SPAN CLASS="cmnt"> relies on implicitly-declared </SPAN>X::operator=(const X&amp;)
    }
</PRE>

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