[Boost-users] help with boost/numeric/operators.hpp

Subject: [Boost-users] help with boost/numeric/operators.hpp
From: Robert Ramey (ramey_at_[hidden])
Date: 2012-01-03 14:03:20

I'm haveing some problems figuring out how to use boost/numeric/operators 
library.

OK - I understand how to use

template<class T>
struct my_type : boost::numeric::operators<T> {
    T & operator+=(T & rhs);
    // automatically generate operator+, etc
   // ...
};

so that one can use
    my_type<int> x, y, z;
    z = x + y;
    // etc..

There is a simple example like this in the documentation.  So far so good.

Now given:

int & operator+=(int  & lhs, my_type<int>);

I want to use operators<T, U> to generate

int operator+(int  & lhs, my_type<int>);
// etc.

After studying the documenation, examples and code, the best I can come up 
with is:

template<class T, class U>
class helper : public boost::operators<T, U>{
};

T operator+(T & lhs, U & rhs){
    helper<T, U>::operator+(lhs, rhs); // automatically generated + operator
}
// other non member operators forwarding to helper

Am I doing this corrrectly?  How did the authors of operators.hpp intend the
two argument versions to be used?

Robert Ramey