NetNews Offline 2/NetNews Offline Volume 2.iso/news/comp/lang/c++-part1/7983

Internet Message Format | 1996-08-05 | 868 b

Message-ID: <[e-mail]>
Date: Fri, 16 Feb 1996 12:16:25 -0800
From: Randal Kuramoto <[e-mail]>
Organization: PeopleSoft
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Subject: temporary is rvalue or lvalue?
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Path: ple-news-01.peoplesoft.com!

I thought a temporary was an l-value.  In the code below,
is the application of the increment operator to the return value
of Foo() in main() a compiler error?  I even tried to specify
const on the return type of Foo().

struct X
{
    X() : m_i( 0 ) {};
    X& operator++() { ++m_i; return( *this ); };
    int m_i;
};

const X Foo() { return X(); }

int main( int, char** )
{
    X x = ++Foo();    // BC4.52 and VC4.0 say it's okay
    return( 0 );
}