Remove dependency on Boost.StaticAssert

Replaced BOOST_STATIC_ASSERT with C++11 binary static_assert,
with empty message.

In future, this should make it possible to automatically refactor
into C++17 unary static_assert using clang-tidy and
its modernize-unary-static-assert check.

Closes #106

.appveyor.yml

@@ -96,7 +96,6 @@ before_build:
   - git submodule --quiet update --init libs/numeric/conversion
   - git submodule --quiet update --init libs/preprocessor
   - git submodule --quiet update --init libs/smart_ptr
-  - git submodule --quiet update --init libs/static_assert
   - git submodule --quiet update --init libs/test
   - git submodule --quiet update --init libs/type_traits
   ## Transitive
@@ -120,6 +119,7 @@ before_build:
   - git submodule --quiet update --init libs/ratio
   - git submodule --quiet update --init libs/rational
   - git submodule --quiet update --init libs/regex
+  - git submodule --quiet update --init libs/static_assert
   - git submodule --quiet update --init libs/system
   - git submodule --quiet update --init libs/throw_exception
   - git submodule --quiet update --init libs/timer

.travis.yml

@@ -212,7 +212,6 @@ install:
   - git submodule --quiet update --init libs/mpl
   - git submodule --quiet update --init libs/numeric/conversion
   - git submodule --quiet update --init libs/preprocessor
-  - git submodule --quiet update --init libs/static_assert
   - git submodule --quiet update --init libs/test
   - git submodule --quiet update --init libs/type_traits
   ## Transitive
@@ -237,6 +236,7 @@ install:
   - git submodule --quiet update --init libs/ratio
   - git submodule --quiet update --init libs/rational
   - git submodule --quiet update --init libs/regex
+  - git submodule --quiet update --init libs/static_assert
   - git submodule --quiet update --init libs/smart_ptr
   - git submodule --quiet update --init libs/system
   - git submodule --quiet update --init libs/throw_exception

doc/design_guide.rst

@@ -808,7 +808,7 @@ provides a model for such packed pixel formats::
   typedef packed_pixel_type<uint16_t, mpl::vector3_c<unsigned,5,6,5>, rgb_layout_t>::type rgb565_pixel_t;
 
   function_requires<PixelValueConcept<rgb565_pixel_t> >();
-  BOOST_STATIC_ASSERT((sizeof(rgb565_pixel_t)==2));
+  static_assert(sizeof(rgb565_pixel_t) == 2, "");
 
   // define a bgr556 pixel
   typedef packed_pixel_type<uint16_t, mpl::vector3_c<unsigned,5,6,5>, bgr_layout_t>::type bgr556_pixel_t;
@@ -838,7 +838,7 @@ pixels and pixel iterators::
 
   // BGR232 pixel value. It is a packed_pixel of size 1 byte. (The last bit is unused)
   typedef std::iterator_traits<bgr232_ptr_t>::value_type bgr232_pixel_t;
-  BOOST_STATIC_ASSERT((sizeof(bgr232_pixel_t)==1));
+  static_assert(sizeof(bgr232_pixel_t) == 1, "");
 
   bgr232_pixel_t red(0,0,3); // = 0RRGGGBB, = 01100000 = 0x60
 
@@ -1959,7 +1959,7 @@ an example::
   #include <boost/gil/extension/dynamic_image/dynamic_image_all.hpp>
   using namespace boost;
 
-  #define ASSERT_SAME(A,B) BOOST_STATIC_ASSERT((is_same< A,B >::value))
+  #define ASSERT_SAME(A,B) static_assert(is_same< A,B >::value, "")
 
   // Define the set of allowed images
   typedef mpl::vector<rgb8_image_t, cmyk16_planar_image_t> my_images_t;
@@ -2380,7 +2380,7 @@ HomogeneousPixelBasedConcept and metafunctions built on top of them::
 These are metafunctions, some of which return integral types which can
 be evaluated like this::
 
-  BOOST_STATIC_ASSERT(is_planar<rgb8_planar_view_t>::value == true);
+  static_assert(is_planar<rgb8_planar_view_t>::value == true, "");
 
 GIL also supports type analysis metafunctions of the form:
 [pixel_reference/iterator/locator/view/image] + "_is_" +
@@ -2537,10 +2537,10 @@ Here is how to use pixels in generic code::
     gil_function_requires<MutableHomogeneousPixelConcept<RGBPixel> >();
 
     typedef typename color_space_type<GrayPixel>::type gray_cs_t;
-    BOOST_STATIC_ASSERT((boost::is_same<gray_cs_t,gray_t>::value));
+    static_assert(boost::is_same<gray_cs_t,gray_t>::value, "");
 
     typedef typename color_space_type<RGBPixel>::type  rgb_cs_t;
-    BOOST_STATIC_ASSERT((boost::is_same<rgb_cs_t,rgb_t>::value));
+    static_assert(boost::is_same<rgb_cs_t,rgb_t>::value, "");
 
     typedef typename channel_type<GrayPixel>::type gray_channel_t;
     typedef typename channel_type<RGBPixel>::type  rgb_channel_t;

doc/doxygen/design_guide.dox

@@ -886,7 +886,7 @@ channels occupy bits [0..4],[5..9] and [10..15] respectively. GIL provides a mod
 typedef packed_pixel_type<uint16_t, mpl::vector3_c<unsigned,5,6,5>, rgb_layout_t>::type rgb565_pixel_t;
 
 function_requires<PixelValueConcept<rgb565_pixel_t> >();
-BOOST_STATIC_ASSERT((sizeof(rgb565_pixel_t)==2));
+static_assert(sizeof(rgb565_pixel_t) == 2, "");
 
 // define a bgr556 pixel
 typedef packed_pixel_type<uint16_t, mpl::vector3_c<unsigned,5,6,5>, bgr_layout_t>::type bgr556_pixel_t;
@@ -912,7 +912,7 @@ typedef bit_aligned_pixel_iterator<bgr232_ref_t> bgr232_ptr_t;
 
 // BGR232 pixel value. It is a packed_pixel of size 1 byte. (The last bit is unused)
 typedef std::iterator_traits<bgr232_ptr_t>::value_type bgr232_pixel_t;
-BOOST_STATIC_ASSERT((sizeof(bgr232_pixel_t)==1));
+static_assert(sizeof(bgr232_pixel_t) == 1, "");
 
 bgr232_pixel_t red(0,0,3); // = 0RRGGGBB, = 01100000 = 0x60
 
@@ -1965,7 +1965,7 @@ depth. How can we possibly write this using our generic image? What type is the
 #include <boost/gil/extension/dynamic_image/dynamic_image_all.hpp>
 using namespace boost;
 
-#define ASSERT_SAME(A,B) BOOST_STATIC_ASSERT((is_same< A,B >::value))
+#define ASSERT_SAME(A,B) static_assert(is_same< A,B >::value, "")
 
 // Define the set of allowed images
 typedef mpl::vector<rgb8_image_t, cmyk16_planar_image_t> my_images_t;
@@ -2351,7 +2351,7 @@ template <typename T> struct num_channels { typedef ... type; };
 These are metafunctions, some of which return integral types which can be evaluated like this:
 
 \code
-BOOST_STATIC_ASSERT(is_planar<rgb8_planar_view_t>::value == true);
+static_assert(is_planar<rgb8_planar_view_t>::value == true, "");
 \endcode
 
 \endcode
@@ -2493,10 +2493,10 @@ void gray_to_rgb(const GrayPixel& src, RGBPixel& dst) {
     gil_function_requires<MutableHomogeneousPixelConcept<RGBPixel> >();
 
     typedef typename color_space_type<GrayPixel>::type gray_cs_t;
-    BOOST_STATIC_ASSERT((boost::is_same<gray_cs_t,gray_t>::value));
+    static_assert(boost::is_same<gray_cs_t,gray_t>::value, "");
 
     typedef typename color_space_type<RGBPixel>::type  rgb_cs_t;
-    BOOST_STATIC_ASSERT((boost::is_same<rgb_cs_t,rgb_t>::value));
+    static_assert(boost::is_same<rgb_cs_t,rgb_t>::value, "");
 
     typedef typename channel_type<GrayPixel>::type gray_channel_t;
     typedef typename channel_type<RGBPixel>::type  rgb_channel_t;

include/boost/gil/bit_aligned_pixel_reference.hpp

@@ -130,8 +130,10 @@ struct bit_aligned_pixel_reference {
     template <bool IsMutable2> bit_aligned_pixel_reference(const bit_aligned_pixel_reference<BitField,ChannelBitSizes,Layout,IsMutable2>& p) : _bit_range(p._bit_range) {}
 
     // Grayscale references can be constructed from the channel reference
-    explicit bit_aligned_pixel_reference(const typename kth_element_type<bit_aligned_pixel_reference,0>::type channel0) : _bit_range(static_cast<data_ptr_t>(&channel0), channel0.first_bit()) {
-        BOOST_STATIC_ASSERT((num_channels<bit_aligned_pixel_reference>::value==1));
+    explicit bit_aligned_pixel_reference(typename kth_element_type<bit_aligned_pixel_reference,0>::type const channel0)
+        : _bit_range(static_cast<data_ptr_t>(&channel0), channel0.first_bit())
+    {
+        static_assert(num_channels<bit_aligned_pixel_reference>::value == 1, "");
     }
 
     // Construct from another compatible pixel type
@@ -159,7 +161,11 @@ struct bit_aligned_pixel_reference {
     template <typename Pixel> bool  equal(const Pixel& p, mpl::true_) const { check_compatible<Pixel>(); return static_equal(*this,p); }
 
 private:
-    static void check_gray() {  BOOST_STATIC_ASSERT((is_same<typename Layout::color_space_t, gray_t>::value)); }
+    static void check_gray()
+    {
+        static_assert(is_same<typename Layout::color_space_t, gray_t>::value, "");
+    }
+
     template <typename Channel> void assign(const Channel& chan, mpl::false_) const { check_gray(); gil::at_c<0>(*this)=chan; }
     template <typename Channel> bool equal (const Channel& chan, mpl::false_) const { check_gray(); return gil::at_c<0>(*this)==chan; }
 };

include/boost/gil/channel.hpp

@@ -262,7 +262,7 @@ using bits4 = packed_channel_value<4>;
 assert(channel_traits<bits4>::min_value()==0);
 assert(channel_traits<bits4>::max_value()==15);
 assert(sizeof(bits4)==1);
-BOOST_STATIC_ASSERT((boost::is_integral<bits4>::value));
+static_assert(boost::is_integral<bits4>::value, "");
 \endcode
 */
 

include/boost/gil/color_base_algorithm.hpp

@@ -34,8 +34,8 @@ namespace boost { namespace gil {
 
 Example:
 \code
-BOOST_STATIC_ASSERT((size<rgb8_pixel_t>::value == 3));
-BOOST_STATIC_ASSERT((size<cmyk8_planar_ptr_t>::value == 4));
+static_assert(size<rgb8_pixel_t>::value == 3, "");
+static_assert(size<cmyk8_planar_ptr_t>::value == 4, "");
 \endcode
 */
 
@@ -133,7 +133,7 @@ Example: A function that takes a generic pixel containing a red channel and sets
 template <typename Pixel>
 void set_red_to_max(Pixel& pixel) {
     boost::function_requires<MutablePixelConcept<Pixel> >();
-    BOOST_STATIC_ASSERT((contains_color<Pixel, red_t>::value));
+    static_assert(contains_color<Pixel, red_t>::value, "");
 
     using red_channel_t = typename color_element_type<Pixel, red_t>::type;
     get_color(pixel, red_t()) = channel_traits<red_channel_t>::max_value();
@@ -192,7 +192,7 @@ typename color_element_const_reference_type<ColorBase,Color>::type get_color(con
 Example:
 \code
 using element_t = element_type<rgb8c_planar_ptr_t>::type;
-BOOST_STATIC_ASSERT((boost::is_same<element_t, const uint8_t*>::value));
+static_assert(boost::is_same<element_t, const uint8_t*>::value, "");
 \endcode
 */
 /// \brief Specifies the element type of a homogeneous color base

include/boost/gil/concepts/basic.hpp

@@ -168,7 +168,7 @@ struct SameType
 {
     void constraints()
     {
-        BOOST_STATIC_ASSERT((boost::is_same<T, U>::value_core));
+        static_assert(boost::is_same<T, U>::value_core, "");
     }
 };
 

include/boost/gil/concepts/channel.hpp

@@ -140,7 +140,7 @@ struct ChannelValueConcept
 /// Example:
 ///
 /// \code
-/// BOOST_STATIC_ASSERT((channels_are_compatible<uint8_t, const uint8_t&>::value));
+/// static_assert(channels_are_compatible<uint8_t, const uint8_t&>::value, "");
 /// \endcode
 /// \ingroup ChannelAlgorithm
 template <typename T1, typename T2>  // Models GIL Pixel
@@ -167,7 +167,7 @@ struct ChannelsCompatibleConcept
 {
     void constraints()
     {
-        BOOST_STATIC_ASSERT((channels_are_compatible<Channel1, Channel2>::value));
+        static_assert(channels_are_compatible<Channel1, Channel2>::value, "");
     }
 };
 

include/boost/gil/concepts/color.hpp

@@ -57,7 +57,7 @@ struct ColorSpacesCompatibleConcept
 {
     void constraints()
     {
-        BOOST_STATIC_ASSERT((color_spaces_are_compatible<CS1, CS2>::value));
+        static_assert(color_spaces_are_compatible<CS1, CS2>::value, "");
     }
 };
 

include/boost/gil/concepts/color_base.hpp

@@ -229,7 +229,7 @@ struct HomogeneousColorBaseConcept
         using T0 = typename kth_element_type<ColorBase, 0>::type;
         using TN = typename kth_element_type<ColorBase, num_elements - 1>::type;
 
-        BOOST_STATIC_ASSERT((is_same<T0, TN>::value));   // better than nothing
+        static_assert(is_same<T0, TN>::value, "");   // better than nothing
 
         using R0 = typename kth_element_const_reference_type<ColorBase, 0>::type;
         R0 r = dynamic_at_c(cb, 0);
@@ -296,11 +296,11 @@ struct ColorBasesCompatibleConcept
 {
     void constraints()
     {
-        BOOST_STATIC_ASSERT((is_same
+        static_assert(is_same
             <
                 typename ColorBase1::layout_t::color_space_t,
                 typename ColorBase2::layout_t::color_space_t
-            >::value));
+            >::value, "");
 
 //        using e1 = typename kth_semantic_element_type<ColorBase1,0>::type;
 //        using e2 = typename kth_semantic_element_type<ColorBase2,0>::type;

include/boost/gil/concepts/image.hpp

@@ -141,10 +141,10 @@ struct ImageConcept
         gil_function_requires<RandomAccess2DImageConcept<Image>>();
         gil_function_requires<MutableImageViewConcept<typename Image::view_t>>();
         using coord_t = typename Image::coord_t;
-        BOOST_STATIC_ASSERT(num_channels<Image>::value == mpl::size<typename color_space_type<Image>::type>::value);
+        static_assert(num_channels<Image>::value == mpl::size<typename color_space_type<Image>::type>::value, "");
 
-        BOOST_STATIC_ASSERT((is_same<coord_t, typename Image::x_coord_t>::value));
-        BOOST_STATIC_ASSERT((is_same<coord_t, typename Image::y_coord_t>::value));
+        static_assert(is_same<coord_t, typename Image::x_coord_t>::value, "");
+        static_assert(is_same<coord_t, typename Image::y_coord_t>::value, "");
     }
     Image image;
 };

include/boost/gil/concepts/image_view.hpp

@@ -120,22 +120,22 @@ struct RandomAccessNDImageViewConcept
         gil_function_requires<boost_concepts::RandomAccessTraversalConcept<first_it_type>>();
         gil_function_requires<boost_concepts::RandomAccessTraversalConcept<last_it_type>>();
 
-//        BOOST_STATIC_ASSERT((typename std::iterator_traits<first_it_type>::difference_type, typename point_t::template axis<0>::coord_t>::value));
-//        BOOST_STATIC_ASSERT((typename std::iterator_traits<last_it_type>::difference_type, typename point_t::template axis<N-1>::coord_t>::value));
+//        static_assert(typename std::iterator_traits<first_it_type>::difference_type, typename point_t::template axis<0>::coord_t>::value, "");
+//        static_assert(typename std::iterator_traits<last_it_type>::difference_type, typename point_t::template axis<N-1>::coord_t>::value, "");
 
         // point_t must be an N-dimensional point, each dimension of which must have the same type as difference_type of the corresponding iterator
         gil_function_requires<PointNDConcept<point_t>>();
-        BOOST_STATIC_ASSERT(point_t::num_dimensions==N);
-        BOOST_STATIC_ASSERT((is_same
+        static_assert(point_t::num_dimensions == N, "");
+        static_assert(is_same
             <
                 typename std::iterator_traits<first_it_type>::difference_type,
                 typename point_t::template axis<0>::coord_t
-            >::value));
-        BOOST_STATIC_ASSERT((is_same
+            >::value, "");
+        static_assert(is_same
             <
                 typename std::iterator_traits<last_it_type>::difference_type,
                 typename point_t::template axis<N-1>::coord_t
-            >::value));
+            >::value, "");
 
         point_t p;
         locator lc;
@@ -215,7 +215,7 @@ struct RandomAccess2DImageViewConcept
     void constraints()
     {
         gil_function_requires<RandomAccessNDImageViewConcept<View>>();
-        BOOST_STATIC_ASSERT(View::num_dimensions==2);
+        static_assert(View::num_dimensions == 2, "");
 
         // TODO: This executes the requirements for RandomAccessNDLocatorConcept again. Fix it to improve compile time
         gil_function_requires<RandomAccess2DLocatorConcept<typename View::locator>>();
@@ -373,7 +373,7 @@ struct ImageViewConcept
         // TODO: This executes the requirements for RandomAccess2DLocatorConcept again. Fix it to improve compile time
         gil_function_requires<PixelLocatorConcept<typename View::xy_locator>>();
 
-        BOOST_STATIC_ASSERT((is_same<typename View::x_coord_t, typename View::y_coord_t>::value));
+        static_assert(is_same<typename View::x_coord_t, typename View::y_coord_t>::value, "");
 
         using coord_t = typename View::coord_t; // 1D difference type (same for all dimensions)
         std::size_t num_chan = view.num_channels(); ignore_unused_variable_warning(num_chan);
@@ -532,7 +532,7 @@ struct ViewsCompatibleConcept
 {
     void constraints()
     {
-        BOOST_STATIC_ASSERT((views_are_compatible<V1, V2>::value));
+        static_assert(views_are_compatible<V1, V2>::value, "");
     }
 };
 

include/boost/gil/concepts/pixel.hpp

@@ -63,7 +63,7 @@ struct PixelConcept
         gil_function_requires<ColorBaseConcept<P>>();
         gil_function_requires<PixelBasedConcept<P>>();
 
-        BOOST_STATIC_ASSERT((is_pixel<P>::value));
+        static_assert(is_pixel<P>::value, "");
         static const bool is_mutable = P::is_mutable;
         ignore_unused_variable_warning(is_mutable);
 
@@ -99,7 +99,7 @@ struct MutablePixelConcept
     void constraints()
     {
         gil_function_requires<PixelConcept<P>>();
-        BOOST_STATIC_ASSERT(P::is_mutable);
+        static_assert(P::is_mutable, "");
     }
 };
 
@@ -187,7 +187,7 @@ struct HomogeneousPixelValueConcept
     {
         gil_function_requires<HomogeneousPixelConcept<P>>();
         gil_function_requires<Regular<P>>();
-        BOOST_STATIC_ASSERT((is_same<P, typename P::value_type>::value));
+        static_assert(is_same<P, typename P::value_type>::value, "");
     }
 };
 
@@ -258,7 +258,7 @@ struct PixelsCompatibleConcept
 {
     void constraints()
     {
-        BOOST_STATIC_ASSERT((pixels_are_compatible<P1, P2>::value));
+        static_assert(pixels_are_compatible<P1, P2>::value, "");
     }
 };
 

include/boost/gil/concepts/pixel_iterator.hpp

@@ -354,7 +354,7 @@ struct IteratorAdaptorConcept
         using base_t = typename iterator_adaptor_get_base<Iterator>::type;
         gil_function_requires<boost_concepts::ForwardTraversalConcept<base_t>>();
 
-        BOOST_STATIC_ASSERT(is_iterator_adaptor<Iterator>::value);
+        static_assert(is_iterator_adaptor<Iterator>::value, "");
         using rebind_t = typename iterator_adaptor_rebind<Iterator, void*>::type;
 
         base_t base = it.base();