🚀 go-pugleaf

In article <47qnbu$f48@oznet03.ozemail.com.au>, John Max Skaller <maxtal@suphys.physics.su.oz.au> writes:
|> jjb@watson.ibm.com (John Barton) wrote:
|> >In article <47dn87$a17@sunsystem5.informatik.tu-muenchen.de>,
|> >|> You can extend this idea:
|> >|>
|> >|> template<class T> T  operator- (T&a, T&b) { return a + (-b); }
|> >|> template<class T> T  operator- (T&a)      { return 0 - a; }
|> >|> template<class T> T& operator+ (T&a)      { return a; }
|> >|> template<class T> T& operator++(T&a)      { return a += 1; }
|> >|> template<class T> T& operator++(T&a,int)  { return ++a; }
|> >
|> >This will not work: it prevent you from writing any templates
|> >for these operators over types that do not have "1" or "0"
|> >or that need a definition other than the one above.
|>
|> How does it prevent it? [Quote WP ??]

template<class T>
Matrix<T> operator-(Matrix<T>& rhs) { /* doesn't matter what I code here */ }

The global operator-(T&) will always win over any more
specific template like the one above.  Unless the standard has
changed here as well.

--
John.

John J. Barton        jjb@watson.ibm.com            (914)784-6645
	<http://www.research.ibm.com/xw-SoftwareTechnology>
H1-C13 IBM Watson Research Center P.O. Box 704 Hawthorne NY 10598

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