[Boost-commit] svn:boost r74159 - in trunk: boost/units boost/units/detail libs/units/test

Subject: [Boost-commit] svn:boost r74159 - in trunk: boost/units boost/units/detail libs/units/test
From: steven_at_[hidden]
Date: 2011-08-30 11:07:49

Author: steven_watanabe
Date: 2011-08-30 11:07:48 EDT (Tue, 30 Aug 2011)
New Revision: 74159
URL: http://svn.boost.org/trac/boost/changeset/74159

Log:
Never return one from conversion_factor.
Text files modified: 
   trunk/boost/units/conversion.hpp          |     6 ++++--                                  
   trunk/boost/units/detail/one.hpp          |    11 +++++++++++                             
   trunk/libs/units/test/test_conversion.cpp |     2 ++                                      
   3 files changed, 17 insertions(+), 2 deletions(-)

Modified: trunk/boost/units/conversion.hpp
==============================================================================
--- trunk/boost/units/conversion.hpp	(original)
+++ trunk/boost/units/conversion.hpp	2011-08-30 11:07:48 EDT (Tue, 30 Aug 2011)
@@ -170,10 +170,12 @@
 /// Find the conversion factor between two units.
 template<class FromUnit,class ToUnit>
 inline
-typename detail::conversion_factor_helper<FromUnit, ToUnit>::type
+typename one_to_double_type<
+    typename detail::conversion_factor_helper<FromUnit, ToUnit>::type
+>::type
 conversion_factor(const FromUnit&,const ToUnit&)
 {
-    return(detail::conversion_factor_helper<FromUnit, ToUnit>::value());
+    return(one_to_double(detail::conversion_factor_helper<FromUnit, ToUnit>::value()));
 }
 
 } // namespace units

Modified: trunk/boost/units/detail/one.hpp
==============================================================================
--- trunk/boost/units/detail/one.hpp	(original)
+++ trunk/boost/units/detail/one.hpp	2011-08-30 11:07:48 EDT (Tue, 30 Aug 2011)
@@ -102,6 +102,17 @@
     return(1 > t);
 }
 
+template<class T>
+T one_to_double(const T& t) { return t; }
+
+inline double one_to_double(const one&) { return 1.0; }
+
+template<class T>
+struct one_to_double_type { typedef T type; };
+
+template<>
+struct one_to_double_type<one> { typedef double type; };
+
 } // namespace units
 
 } // namespace boost

Modified: trunk/libs/units/test/test_conversion.cpp
==============================================================================
--- trunk/libs/units/test/test_conversion.cpp	(original)
+++ trunk/libs/units/test/test_conversion.cpp	2011-08-30 11:07:48 EDT (Tue, 30 Aug 2011)
@@ -82,6 +82,8 @@
     bu::quantity<bu::si::force> F5(20 * bu::cgs::dyne);
     BOOST_UNITS_CHECK_CLOSE(F5.value(), 2.0e-4);
 
+    // same type
+    BOOST_CHECK_EQUAL(boost::units::conversion_factor(si_length(), si_length()), 1.0);
 }
 
 BOOST_AUTO_TEST_CASE(test_dimensionless_conversions) {