[boost] Reversed operator helpers?

From: Daryle Walker (dwalker07_at_[hidden])
Date: 2003-07-30 23:51:00

In <boost/operators.hpp> we have helper classes that can generate 
"operator OP" from "operator OP=", where "OP" can be "+", "/", ">>", 
etc.  What about types and algorithms where the non-assignment version 
is easier than the assignment version?  Should we have reverse helpers?

//================================================================
template < std::size_t N >
        class bitsetint;

template < std::size_t M, std::size_t N >
        bitsetint<static_max<M,N>::value + 1>
          operator +( bitsetint<M>, bitsetint<N> );

template < std::size_t M, std::size_t N >
        bitsetint<M * N>
          operator *( bitsetint<M>, bitsetint<N> );
//================================================================

This is an example where the non-assignment versions of the operations 
can give a more-complete answer than having to shoehorn the results 
into a variable like the first operand.  The assignment versions should 
call the code given here (to later chop off the most significant bits) 
to save work and enforce consistency.

Daryle