id	summary	reporter	owner	description	type	status	milestone	component	version	severity	resolution	keywords	cc
2938	[operators] BOOST_OPERATOR2_LEFT prevents builtin types from being used as first template parameter	Arne Mertz <boost@…>	Daniel Frey	"Minimal code example:

#include <boost/operators.hpp>


class X : public boost::subtractable2_left<double, X>
{
public:
  friend double& operator-= (double& lhs, X const&)
  { return lhs; }

  operator double() const {return 1.0;}
};


int main()
{
  X x;
  double d = x - 0.5; //ERROR: left operand of op-= has to be l-value
}

#defines BOOST_NO_NRVO and BOOST_FORCE_SYMMETRIC_OPERATORS are not set, so the short implementation in line 240 (as of Sat April 4th, 2009) is used: return T( lhs ) -= rhs;
on msvc 2008 express this does not work with T being a builtin type."	Bugs	closed	Boost 1.39.0	operators	Boost 1.38.0	Problem	invalid