Prevent binding polynomial<U>s to the scalar operators.

Author: kundor

include/boost/math/tools/polynomial.hpp

@@ -21,6 +21,7 @@
 #include <boost/math/tools/real_cast.hpp>
 #include <boost/math/special_functions/binomial.hpp>
 #include <boost/operators.hpp>
+#include <boost/type_traits/is_convertible.hpp>
 
 #include <vector>
 #include <ostream>
@@ -377,15 +378,17 @@ class polynomial : ordered_euclidean_ring_operators< polynomial<T> >
    }
 
    template <class U>
-   polynomial& operator /=(const U& value)
+   BOOST_DEDUCED_TYPENAME enable_if<boost::is_convertible<U,T>, polynomial >::type&
+   operator /=(const U& value)
    {
        division(value);
        normalize();
        return *this;
    }
 
    template <class U>
-   polynomial& operator %=(const U& /*value*/)
+   BOOST_DEDUCED_TYPENAME enable_if<boost::is_convertible<U,T>, polynomial >::type&
+   operator %=(const U& /*value*/)
    {
        // We can always divide by a scalar, so there is no remainder:
        *this = zero_element(std::multiplies<polynomial>());
@@ -431,27 +434,12 @@ class polynomial : ordered_euclidean_ring_operators< polynomial<T> >
        return *this;
    }
 
-   template <typename U>
-   polynomial& operator /=(const polynomial<U>& value)
-   {
-       *this = quotient_remainder(*this, polynomial(value)).first;
-       return *this;
-   }
-
    polynomial& operator %=(const polynomial& value)
    {
        *this = quotient_remainder(*this, value).second;
        return *this;
    }
 
-
-   template <typename U>
-   polynomial& operator %=(const polynomial<U>& value)
-   {
-       *this = quotient_remainder(*this, polynomial(value)).second;
-       return *this;
-   }
-
    template <typename U>
    polynomial& operator >>=(U const &n)
    {