remove static_visitor usage and rely on automatic result type deduction

(NOTE: expression_evaluator requires ```using result_type = T1;``` )
2015-01-07 11:35:21 +01:00 · 2015-01-07 11:35:21 +01:00 · c2ea32feac
commit c2ea32feac
parent b28aadcf41
45 changed files with 99 additions and 99 deletions
--- a/bindings/python/mapnik_symbolizer.cpp
+++ b/bindings/python/mapnik_symbolizer.cpp
@ -105,7 +105,7 @@ std::shared_ptr<mapnik::symbolizer_base::value_type> numeric_wrapper(const objec
    return result;
 }

-struct extract_python_object : public mapnik::util::static_visitor<boost::python::object>
+struct extract_python_object
 {
    using result_type = boost::python::object;

@ -153,7 +153,7 @@ std::size_t hash_impl_2(T const& sym)
    return mapnik::symbolizer_hash::value<T>(sym);
 }

-struct extract_underlying_type_visitor : mapnik::util::static_visitor<boost::python::object>
+struct extract_underlying_type_visitor
 {
    template <typename T>
    boost::python::object operator() (T const& sym) const
--- a/bindings/python/mapnik_value_converter.hpp
+++ b/bindings/python/mapnik_value_converter.hpp
@ -31,7 +31,7 @@

 namespace boost { namespace python {

-    struct value_converter : public mapnik::util::static_visitor<PyObject*>
+    struct value_converter
    {
        PyObject * operator() (mapnik::value_integer val) const
        {
--- a/demo/viewer/styles_model.cpp
+++ b/demo/viewer/styles_model.cpp
@ -122,7 +122,7 @@ private:
 };


-struct symbolizer_info : public mapnik::util::static_visitor<QString>
+struct symbolizer_info
 {
    QString operator() (mapnik::point_symbolizer const& sym) const
    {
@ -185,7 +185,7 @@ struct symbolizer_info : public mapnik::util::static_visitor<QString>
    }
 };

-struct symbolizer_icon : public mapnik::util::static_visitor<QIcon>
+struct symbolizer_icon
 {
    QIcon operator() (mapnik::polygon_symbolizer const& sym) const
    {
--- a/include/mapnik/attribute_collector.hpp
+++ b/include/mapnik/attribute_collector.hpp
@ -52,7 +52,7 @@
 namespace mapnik {

 template <typename Container>
-struct expression_attributes : util::static_visitor<void>
+struct expression_attributes
 {
    explicit expression_attributes(Container& names)
        : names_(names) {}
@ -107,7 +107,7 @@ public:
 };

 template <typename Container>
-struct extract_attribute_names : util::static_visitor<void>
+struct extract_attribute_names
 {
    explicit extract_attribute_names(Container& names)
        : names_(names),
@ -159,7 +159,7 @@ private:
    expression_attributes<std::set<std::string> > f_attr_;
 };

-struct symbolizer_attributes : public util::static_visitor<>
+struct symbolizer_attributes
 {
    symbolizer_attributes(std::set<std::string>& names,
                          double & filter_factor)
--- a/include/mapnik/evaluate_global_attributes.hpp
+++ b/include/mapnik/evaluate_global_attributes.hpp
@ -39,7 +39,7 @@ namespace mapnik {
 namespace {

 template <typename T, typename Attributes>
-struct evaluate_expression : util::static_visitor<T>
+struct evaluate_expression
 {
    using value_type = T;

@ -133,7 +133,7 @@ struct evaluate_expression : util::static_visitor<T>
 };

 template <typename T>
-struct evaluate_expression<T, boost::none_t> : util::static_visitor<T>
+struct evaluate_expression<T, boost::none_t>
 {
    using value_type = T;

@ -274,7 +274,7 @@ std::tuple<T,bool> pre_evaluate_expression (expression_ptr const& expr)
 struct evaluate_global_attributes : mapnik::noncopyable
 {
    template <typename Attributes>
-    struct evaluator : util::static_visitor<>
+    struct evaluator
    {
        evaluator(symbolizer_base::cont_type::value_type & prop, Attributes const& attributes)
            : prop_(prop),
@ -296,7 +296,7 @@ struct evaluate_global_attributes : mapnik::noncopyable
    };

    template <typename Attributes>
-    struct extract_symbolizer : util::static_visitor<>
+    struct extract_symbolizer
    {
        extract_symbolizer(Attributes const& attributes)
            : attributes_(attributes) {}
--- a/include/mapnik/expression_evaluator.hpp
+++ b/include/mapnik/expression_evaluator.hpp
@ -35,12 +35,12 @@ namespace mapnik
 {

 template <typename T0, typename T1, typename T2>
-struct evaluate : util::static_visitor<T1>
+struct evaluate
 {
    using feature_type = T0;
    using value_type = T1;
    using variable_type = T2;
-
+    using result_type = T1; //  we need this because automatic result_type deduction fails
    explicit evaluate(feature_type const& f, variable_type const& v)
        : feature_(f),
          vars_(v) {}
--- a/include/mapnik/image_data_any.hpp
+++ b/include/mapnik/image_data_any.hpp
@ -40,7 +40,7 @@ using image_data_base = util::variant<image_data_null, image_data_rgba8, image_d

 namespace detail {

-struct get_bytes_visitor : util::static_visitor<unsigned char*>
+struct get_bytes_visitor
 {
    template <typename T>
    unsigned char* operator()(T & data)
@ -49,7 +49,7 @@ struct get_bytes_visitor : util::static_visitor<unsigned char*>
    }
 };

-struct get_bytes_visitor_const : util::static_visitor<unsigned char const*>
+struct get_bytes_visitor_const
 {
    template <typename T>
    unsigned char const* operator()(T const& data) const
@ -58,7 +58,7 @@ struct get_bytes_visitor_const : util::static_visitor<unsigned char const*>
    }
 };

-struct get_width_visitor : util::static_visitor<std::size_t>
+struct get_width_visitor
 {
    template <typename T>
    std::size_t operator()(T const& data) const
@ -67,7 +67,7 @@ struct get_width_visitor : util::static_visitor<std::size_t>
    }
 };

-struct get_height_visitor : util::static_visitor<std::size_t>
+struct get_height_visitor
 {
    template <typename T>
    std::size_t operator()(T const& data) const
--- a/include/mapnik/image_filter.hpp
+++ b/include/mapnik/image_filter.hpp
@ -761,7 +761,7 @@ void apply_filter(Src & src, invert const& /*op*/)
 }

 template <typename Src>
-struct filter_visitor : util::static_visitor<void>
+struct filter_visitor
 {
    filter_visitor(Src & src)
    : src_(src) {}
@ -775,7 +775,7 @@ struct filter_visitor : util::static_visitor<void>
    Src & src_;
 };

-struct filter_radius_visitor : util::static_visitor<void>
+struct filter_radius_visitor
 {
    int & radius_;
    filter_radius_visitor(int & radius)
--- a/include/mapnik/image_filter_types.hpp
+++ b/include/mapnik/image_filter_types.hpp
@ -267,7 +267,7 @@ inline std::ostream& operator<< (std::ostream& os, colorize_alpha const& filter)


 template <typename Out>
-struct to_string_visitor : util::static_visitor<void>
+struct to_string_visitor
 {
    to_string_visitor(Out & out)
    : out_(out) {}
--- a/include/mapnik/json/feature_grammar.hpp
+++ b/include/mapnik/json/feature_grammar.hpp
@ -46,7 +46,7 @@ namespace standard_wide =  boost::spirit::standard_wide;
 using standard_wide::space_type;

 class attribute_value_visitor
-    : public mapnik::util::static_visitor<mapnik::value>
+
 {
 public:
    attribute_value_visitor(mapnik::transcoder const& tr)
--- a/include/mapnik/json/geometry_util.hpp
+++ b/include/mapnik/json/geometry_util.hpp
@ -31,7 +31,7 @@ namespace mapnik { namespace json {

 // geometries
 template <typename Path>
-struct create_point : util::static_visitor<>
+struct create_point
 {
    explicit create_point(Path & path)
        : path_(path) {}
@ -49,7 +49,7 @@ struct create_point : util::static_visitor<>
 };

 template <typename Path>
-struct create_linestring : util::static_visitor<>
+struct create_linestring
 {
    explicit create_linestring(Path & path)
        : path_(path) {}
@ -77,7 +77,7 @@ struct create_linestring : util::static_visitor<>
 };

 template <typename Path>
-struct create_polygon : util::static_visitor<>
+struct create_polygon
 {
    explicit create_polygon(Path & path)
        : path_(path) {}
@ -111,7 +111,7 @@ struct create_polygon : util::static_visitor<>
 // multi-geometries

 template <typename Path>
-struct create_multipoint : util::static_visitor<>
+struct create_multipoint
 {
    explicit create_multipoint(Path & path)
        : path_(path) {}
@ -133,7 +133,7 @@ struct create_multipoint : util::static_visitor<>
 };

 template <typename Path>
-struct create_multilinestring : util::static_visitor<>
+struct create_multilinestring
 {
    explicit create_multilinestring(Path & path)
        : path_(path) {}
@ -163,7 +163,7 @@ struct create_multilinestring : util::static_visitor<>
 };

 template <typename Path>
-struct create_multipolygon : util::static_visitor<>
+struct create_multipolygon
 {
    explicit create_multipolygon(Path & path)
        : path_(path) {}
--- a/include/mapnik/json/symbolizer_grammar.hpp
+++ b/include/mapnik/json/symbolizer_grammar.hpp
@ -45,7 +45,7 @@ namespace standard_wide =  boost::spirit::standard_wide;
 using standard_wide::space_type;

 template <typename Symbolizer>
-struct json_value_visitor : mapnik::util::static_visitor<>
+struct json_value_visitor
 {
    json_value_visitor(Symbolizer & sym, mapnik::keys key)
        : sym_(sym), key_(key) {}
@ -82,7 +82,7 @@ struct json_value_visitor : mapnik::util::static_visitor<>
 };

 template <typename T>
-struct put_property_visitor : mapnik::util::static_visitor<>
+struct put_property_visitor
 {
    using value_type = T;

--- a/include/mapnik/json/topojson_utils.hpp
+++ b/include/mapnik/json/topojson_utils.hpp
@ -30,7 +30,7 @@

 namespace mapnik { namespace topojson {

-struct bounding_box_visitor : public mapnik::util::static_visitor<box2d<double> >
+struct bounding_box_visitor
 {
    bounding_box_visitor(topology const& topo)
        : topo_(topo) {}
--- a/include/mapnik/markers_placement.hpp
+++ b/include/mapnik/markers_placement.hpp
@ -44,7 +44,7 @@ public:
                                            markers_vertex_first_placement<Locator, Detector>,
                                            markers_vertex_last_placement<Locator, Detector>>;

-    class get_point_visitor : public util::static_visitor<bool>
+    class get_point_visitor
    {
    public:
        get_point_visitor(double &x, double &y, double &angle, bool ignore_placement)
--- a/include/mapnik/params_impl.hpp
+++ b/include/mapnik/params_impl.hpp
@ -121,7 +121,7 @@ boost::optional<T> param_cast(std::string const& source)
 } // end namespace detail

 template <typename T>
-struct value_extractor_visitor : public util::static_visitor<>
+struct value_extractor_visitor
 {

    value_extractor_visitor(boost::optional<T> & var)
--- a/include/mapnik/renderer_common/process_group_symbolizer.hpp
+++ b/include/mapnik/renderer_common/process_group_symbolizer.hpp
@ -154,7 +154,7 @@ using render_thunk_list = std::list<render_thunk_ptr>;
 // The bounding boxes can be used for layout, and the thunks are
 // used to re-render at locations according to the group layout.

-struct render_thunk_extractor : public util::static_visitor<>
+struct render_thunk_extractor
 {
    render_thunk_extractor(box2d<double> & box,
                           render_thunk_list & thunks,
--- a/include/mapnik/renderer_common/process_raster_symbolizer.hpp
+++ b/include/mapnik/renderer_common/process_raster_symbolizer.hpp
@ -44,7 +44,7 @@ namespace mapnik {
 namespace detail {

 template <typename F>
-struct image_data_dispatcher :  util::static_visitor<void>
+struct image_data_dispatcher
 {
    using composite_function = F;
    image_data_dispatcher(int start_x, int start_y,
@ -105,7 +105,7 @@ private:
 };

 template <typename F>
-struct image_data_warp_dispatcher :  util::static_visitor<void>
+struct image_data_warp_dispatcher
 {
    using composite_function = F;
    image_data_warp_dispatcher(proj_transform const& prj_trans,
--- a/include/mapnik/symbolizer.hpp
+++ b/include/mapnik/symbolizer.hpp
@ -339,7 +339,7 @@ struct evaluate_expression_wrapper<mapnik::font_feature_settings>
 };

 template <typename T>
-struct extract_value : public util::static_visitor<T>
+struct extract_value
 {
    using result_type = T;

@ -379,7 +379,7 @@ struct extract_value : public util::static_visitor<T>
 };

 template <typename T1>
-struct extract_raw_value : public util::static_visitor<T1>
+struct extract_raw_value
 {
    using result_type = T1;

--- a/include/mapnik/symbolizer_dispatch.hpp
+++ b/include/mapnik/symbolizer_dispatch.hpp
@ -67,7 +67,7 @@ struct process_impl<false>
 * \param sym        Symbolizer object
 */
 template <typename Processor>
-struct symbolizer_dispatch : public util::static_visitor<>
+struct symbolizer_dispatch
 {
    symbolizer_dispatch(Processor & output,
                        mapnik::feature_impl & f,
--- a/include/mapnik/symbolizer_hash.hpp
+++ b/include/mapnik/symbolizer_hash.hpp
@ -33,7 +33,7 @@

 namespace mapnik {

-struct property_value_hash_visitor : util::static_visitor<std::size_t>
+struct property_value_hash_visitor
 {
    std::size_t operator() (color const& val) const
    {
@ -82,7 +82,7 @@ struct symbolizer_hash
    }
 };

-struct symbolizer_hash_visitor : util::static_visitor<std::size_t>
+struct symbolizer_hash_visitor
 {
    template <typename Symbolizer>
    std::size_t operator() (Symbolizer const& sym) const
--- a/include/mapnik/symbolizer_utils.hpp
+++ b/include/mapnik/symbolizer_utils.hpp
@ -129,7 +129,7 @@ struct symbolizer_traits<dot_symbolizer>
 // symbolizer name impl
 namespace detail {

-struct symbolizer_name_impl : public util::static_visitor<std::string>
+struct symbolizer_name_impl
 {
 public:
    template <typename Symbolizer>
@ -150,7 +150,7 @@ inline std::string symbolizer_name(symbolizer const& sym)
 /*

 template <typename Meta>
-class symbolizer_property_value_string : public util::static_visitor<std::string>
+class symbolizer_property_value_string
 {
 public:
    symbolizer_property_value_string (Meta const& meta)
@ -237,7 +237,7 @@ private:
    Meta const& meta_;
 };

-struct symbolizer_to_json : public util::static_visitor<std::string>
+struct symbolizer_to_json
 {
    using result_type = std::string;

--- a/include/mapnik/tiff_io.hpp
+++ b/include/mapnik/tiff_io.hpp
@ -179,7 +179,7 @@ struct tiff_config

 };

-struct tag_setter : public mapnik::util::static_visitor<>
+struct tag_setter
 {
    tag_setter(TIFF * output, tiff_config & config)
        : output_(output),
@ -270,7 +270,7 @@ void set_tiff_config(TIFF* output, tiff_config & config)
    // Set the compression for the TIFF
    TIFFSetField(output, TIFFTAG_COMPRESSION, config.compression);

-    if (COMPRESSION_ADOBE_DEFLATE == config.compression 
+    if (COMPRESSION_ADOBE_DEFLATE == config.compression
        || COMPRESSION_DEFLATE == config.compression
        || COMPRESSION_LZW == config.compression)
    {
@ -332,7 +332,7 @@ void save_as_tiff(T1 & file, T2 const& image, tiff_config & config)
    else if (TIFF_WRITE_STRIPPED == config.method)
    {
        std::size_t rows_per_strip = config.rows_per_strip;
-        if (0 == rows_per_strip) 
+        if (0 == rows_per_strip)
        {
            rows_per_strip = height;
        }
@ -359,8 +359,8 @@ void save_as_tiff(T1 & file, T2 const& image, tiff_config & config)
    {
        int tile_width = config.tile_width;
        int tile_height = config.tile_height;
-        
-        if (0 == tile_height) 
+
+        if (0 == tile_height)
        {
            tile_height = height;
            if (height % 16 > 0)
@ -385,7 +385,7 @@ void save_as_tiff(T1 & file, T2 const& image, tiff_config & config)
        int end_x = (width / tile_width + 1) * tile_width;
        end_y = std::min(end_y, height);
        end_x = std::min(end_x, width);
-        
+
        for (int y = 0; y < end_y; y += tile_height)
        {
            int ty1 = std::min(height, y + tile_height) - y;
--- a/include/mapnik/transform_expression.hpp
+++ b/include/mapnik/transform_expression.hpp
@ -192,7 +192,7 @@ inline void clear(transform_node& val)

 namespace  {

-struct is_null_transform_node : public mapnik::util::static_visitor<bool>
+struct is_null_transform_node
 {
    bool operator() (value const& val) const
    {
--- a/include/mapnik/transform_processor.hpp
+++ b/include/mapnik/transform_processor.hpp
@ -46,7 +46,7 @@ struct transform_processor
    using transform_type = agg::trans_affine;

    template <typename Container>
-    struct attribute_collector : util::static_visitor<void>
+    struct attribute_collector
    {
        expression_attributes<Container> collect_;

@ -97,7 +97,7 @@ struct transform_processor
        }
    };

-    struct node_evaluator : util::static_visitor<void>
+    struct node_evaluator
    {
        node_evaluator(transform_type& tr,
                       feature_type const& feat,
--- a/include/mapnik/value.hpp
+++ b/include/mapnik/value.hpp
@ -72,7 +72,7 @@ using value_base = util::variant<value_null, value_bool, value_integer,value_dou
 namespace impl {

 struct equals
-    : public util::static_visitor<bool>
+
 {
    bool operator() (value_integer lhs, value_double rhs) const
    {
@ -124,7 +124,7 @@ struct equals
 };

 struct not_equals
-    : public util::static_visitor<bool>
+
 {
    template <typename T, typename U>
    bool operator() (const T &, const U &) const
@ -186,7 +186,7 @@ struct not_equals
 };

 struct greater_than
-    : public util::static_visitor<bool>
+
 {
    template <typename T, typename U>
    bool operator()(const T &, const U &) const
@ -222,7 +222,7 @@ struct greater_than
 };

 struct greater_or_equal
-    : public util::static_visitor<bool>
+
 {
    template <typename T, typename U>
    bool operator()(const T &, const U &) const
@ -258,7 +258,7 @@ struct greater_or_equal
 };

 struct less_than
-    : public util::static_visitor<bool>
+
 {
    template <typename T, typename U>
    bool operator()(const T &, const U &) const
@ -295,7 +295,7 @@ struct less_than
 };

 struct less_or_equal
-    : public util::static_visitor<bool>
+
 {
    template <typename T, typename U>
    bool operator()(const T &, const U &) const
@ -332,7 +332,7 @@ struct less_or_equal
 };

 template <typename V>
-struct add : public util::static_visitor<V>
+struct add
 {
    using value_type = V;
    value_type operator() (value_unicode_string const& lhs ,
@ -398,7 +398,7 @@ struct add : public util::static_visitor<V>
 };

 template <typename V>
-struct sub : public util::static_visitor<V>
+struct sub
 {
    using value_type = V;
    template <typename T1, typename T2>
@ -436,7 +436,7 @@ struct sub : public util::static_visitor<V>
 };

 template <typename V>
-struct mult : public util::static_visitor<V>
+struct mult
 {
    using value_type = V;
    template <typename T1, typename T2>
@ -473,7 +473,7 @@ struct mult : public util::static_visitor<V>
 };

 template <typename V>
-struct div: public util::static_visitor<V>
+struct div
 {
    using value_type = V;
    template <typename T1, typename T2>
@ -514,7 +514,7 @@ struct div: public util::static_visitor<V>
 };

 template <typename V>
-struct mod: public util::static_visitor<V>
+struct mod
 {
    using value_type = V;
    template <typename T1, typename T2>
@ -558,7 +558,7 @@ struct mod: public util::static_visitor<V>
 };

 template <typename V>
-struct negate : public util::static_visitor<V>
+struct negate
 {
    using value_type = V;

@ -589,7 +589,7 @@ template <typename T>
 struct convert {};

 template <>
-struct convert<value_bool> : public util::static_visitor<value_bool>
+struct convert<value_bool>
 {
    value_bool operator() (value_bool val) const
    {
@ -614,7 +614,7 @@ struct convert<value_bool> : public util::static_visitor<value_bool>
 };

 template <>
-struct convert<value_double> : public util::static_visitor<value_double>
+struct convert<value_double>
 {
    value_double operator() (value_double val) const
    {
@ -653,7 +653,7 @@ struct convert<value_double> : public util::static_visitor<value_double>
 };

 template <>
-struct convert<value_integer> : public util::static_visitor<value_integer>
+struct convert<value_integer>
 {
    value_integer operator() (value_integer val) const
    {
@ -692,7 +692,7 @@ struct convert<value_integer> : public util::static_visitor<value_integer>
 };

 template <>
-struct convert<std::string> : public util::static_visitor<std::string>
+struct convert<std::string>
 {
    template <typename T>
    std::string operator() (T val) const
@ -723,7 +723,7 @@ struct convert<std::string> : public util::static_visitor<std::string>
    }
 };

-struct to_unicode : public util::static_visitor<value_unicode_string>
+struct to_unicode
 {

    template <typename T>
@ -753,7 +753,7 @@ struct to_unicode : public util::static_visitor<value_unicode_string>
    }
 };

-struct to_expression_string : public util::static_visitor<std::string>
+struct to_expression_string
 {
    explicit to_expression_string(char quote = '\'')
        : quote_(quote) {}
@ -947,7 +947,7 @@ using value_adl_barrier::operator<<;

 namespace detail {

-struct is_null_visitor : public util::static_visitor<bool>
+struct is_null_visitor
 {
    bool operator() (value const& val) const
    {
--- a/include/mapnik/value_hash.hpp
+++ b/include/mapnik/value_hash.hpp
@ -42,7 +42,7 @@ inline void hash_combine(std::size_t & seed, T const& v)
    seed ^= hasher(v) + 0x9e3779b9 + (seed<<6) + (seed>>2);
 }

-struct value_hasher: public util::static_visitor<std::size_t>
+struct value_hasher
 {
    std::size_t operator() (value_null val) const
    {
--- a/plugins/input/gdal/gdal_featureset.hpp
+++ b/plugins/input/gdal/gdal_featureset.hpp
@ -38,7 +38,7 @@ using gdal_query = mapnik::util::variant<mapnik::query, mapnik::coord2d>;

 class gdal_featureset : public mapnik::Featureset
 {
-    struct query_dispatch : public mapnik::util::static_visitor<mapnik::feature_ptr>
+    struct query_dispatch
    {
        query_dispatch( gdal_featureset & featureset)
            : featureset_(featureset) {}
--- a/plugins/input/geojson/geojson_datasource.cpp
+++ b/plugins/input/geojson/geojson_datasource.cpp
@ -53,7 +53,7 @@ using mapnik::parameters;

 DATASOURCE_PLUGIN(geojson_datasource)

-struct attr_value_converter : public mapnik::util::static_visitor<mapnik::eAttributeType>
+struct attr_value_converter
 {
    mapnik::eAttributeType operator() (mapnik::value_integer) const
    {
--- a/plugins/input/rasterlite/rasterlite_featureset.hpp
+++ b/plugins/input/rasterlite/rasterlite_featureset.hpp
@ -35,7 +35,7 @@ using rasterlite_query = mapnik::util::variant<mapnik::query,mapnik::coord2d>;

 class rasterlite_featureset : public mapnik::Featureset
 {
-    struct query_dispatch : public mapnik::util::static_visitor<mapnik::feature_ptr>
+    struct query_dispatch
    {
        query_dispatch( rasterlite_featureset & featureset)
            : featureset_(featureset) {}
--- a/plugins/input/topojson/topojson_datasource.cpp
+++ b/plugins/input/topojson/topojson_datasource.cpp
@ -44,7 +44,7 @@ using mapnik::parameters;

 DATASOURCE_PLUGIN(topojson_datasource)

-struct attr_value_converter : public mapnik::util::static_visitor<mapnik::eAttributeType>
+struct attr_value_converter
 {
    mapnik::eAttributeType operator() (mapnik::value_integer /*val*/) const
    {
@ -82,7 +82,7 @@ struct attr_value_converter : public mapnik::util::static_visitor<mapnik::eAttri
    }
 };

-struct geometry_type_visitor : public mapnik::util::static_visitor<int>
+struct geometry_type_visitor
 {
    int operator() (mapnik::topojson::point const&) const
    {
@ -114,7 +114,7 @@ struct geometry_type_visitor : public mapnik::util::static_visitor<int>
    }
 };

-struct collect_attributes_visitor : public mapnik::util::static_visitor<void>
+struct collect_attributes_visitor
 {
    mapnik::layer_descriptor & desc_;
    collect_attributes_visitor(mapnik::layer_descriptor & desc):
--- a/plugins/input/topojson/topojson_featureset.cpp
+++ b/plugins/input/topojson/topojson_featureset.cpp
@ -51,7 +51,7 @@ BOOST_GEOMETRY_REGISTER_LINESTRING(std::vector<mapnik::topojson::coordinate>)
 namespace mapnik { namespace topojson {

 struct attribute_value_visitor
-    :  mapnik::util::static_visitor<mapnik::value>
+
 {
 public:
    attribute_value_visitor(mapnik::transcoder const& tr)
@ -84,7 +84,7 @@ void assign_properties(mapnik::feature_impl & feature, T const& geom, mapnik::tr
 }

 template <typename Context>
-struct feature_generator : public mapnik::util::static_visitor<mapnik::feature_ptr>
+struct feature_generator
 {
    feature_generator(Context & ctx,  mapnik::transcoder const& tr, topology const& topo, std::size_t feature_id)
        : ctx_(ctx),
--- a/src/agg/process_group_symbolizer.cpp
+++ b/src/agg/process_group_symbolizer.cpp
@ -43,7 +43,7 @@ namespace mapnik {
 * to render it, and the boxes themselves should already be
 * in the detector from the placement_finder.
 */
-struct thunk_renderer : public util::static_visitor<>
+struct thunk_renderer
 {
    using renderer_type = agg_renderer<image_32>;
    using buffer_type = renderer_type::buffer_type;
--- a/src/cairo/process_group_symbolizer.cpp
+++ b/src/cairo/process_group_symbolizer.cpp
@ -43,7 +43,7 @@ namespace {
 // to render it, and the boxes themselves should already be
 // in the detector from the placement_finder.
 template <typename T>
-struct thunk_renderer : public util::static_visitor<>
+struct thunk_renderer
 {
    using renderer_type = cairo_renderer<T>;

--- a/src/expression_string.cpp
+++ b/src/expression_string.cpp
@ -33,7 +33,7 @@
 namespace mapnik
 {

-struct expression_string : util::static_visitor<void>
+struct expression_string
 {
    explicit expression_string(std::string & str)
        : str_(str) {}
--- a/src/grid/process_group_symbolizer.cpp
+++ b/src/grid/process_group_symbolizer.cpp
@ -53,7 +53,7 @@ namespace mapnik {
 * in the detector from the placement_finder.
 */
 template <typename T0>
-struct thunk_renderer : public util::static_visitor<>
+struct thunk_renderer
 {
    using renderer_type = grid_renderer<T0>;
    using buffer_type = typename renderer_type::buffer_type;
--- a/src/group/group_layout_manager.cpp
+++ b/src/group/group_layout_manager.cpp
@ -31,7 +31,7 @@ namespace mapnik
 {

 // This visitor will process offsets for the given layout
-struct process_layout : public util::static_visitor<>
+struct process_layout
 {
    // The vector containing the existing, centered item bounding boxes
    vector<bound_box> const& member_boxes_;
--- a/src/image.cpp
+++ b/src/image.cpp
@ -52,7 +52,7 @@ image image::read_from_file(std::string const& filename)

 namespace detail {

-struct save_to_file_visitor : mapnik::util::static_visitor<>
+struct save_to_file_visitor
 {
    save_to_file_visitor(std::string const& filename, std::string const& format)
        : filename_(filename),
--- a/src/parse_path.cpp
+++ b/src/parse_path.cpp
@ -53,7 +53,7 @@ path_expression_ptr parse_path(std::string const& str)

 namespace path_processor_detail
 {
-    struct path_visitor_ : util::static_visitor<void>
+    struct path_visitor_
    {
        path_visitor_ (std::string & filename, feature_impl const& f)
            : filename_(filename),
@ -75,7 +75,7 @@ namespace path_processor_detail
        feature_impl const& feature_;
    };

-    struct to_string_ : util::static_visitor<void>
+    struct to_string_
    {
        to_string_ (std::string & str)
            : str_(str) {}
@ -95,7 +95,7 @@ namespace path_processor_detail
        std::string & str_;
    };

-    struct collect_ : util::static_visitor<void>
+    struct collect_
    {
        collect_ (std::set<std::string> & cont)
            : cont_(cont) {}
--- a/src/save_map.cpp
+++ b/src/save_map.cpp
@ -135,7 +135,7 @@ void serialize_group_symbolizer_properties(ptree & sym_node,
                                           bool explicit_defaults);

 template <typename Meta>
-class serialize_symbolizer_property : public util::static_visitor<>
+class serialize_symbolizer_property
 {
 public:
    serialize_symbolizer_property(Meta const& meta,
@ -225,7 +225,7 @@ private:
    bool explicit_defaults_;
 };

-class serialize_symbolizer : public util::static_visitor<>
+class serialize_symbolizer
 {
 public:
    serialize_symbolizer( ptree & r , bool explicit_defaults)
@ -255,7 +255,7 @@ private:
    bool explicit_defaults_;
 };

-class serialize_group_layout : public util::static_visitor<>
+class serialize_group_layout
 {
 public:
    serialize_group_layout(ptree & parent_node, bool explicit_defaults)
--- a/src/svg/output/process_symbolizers.cpp
+++ b/src/svg/output/process_symbolizers.cpp
@ -37,7 +37,7 @@

 namespace mapnik {

-struct symbol_type_dispatch : public util::static_visitor<bool>
+struct symbol_type_dispatch
 {
    template <typename Symbolizer>
    bool operator()(Symbolizer const&) const
--- a/src/text/placements/simple.cpp
+++ b/src/text/placements/simple.cpp
@ -169,7 +169,7 @@ text_placements_simple::text_placements_simple(symbolizer_base::value_type const
   positions_(positions) { }

 namespace detail {
-    struct serialize_positions : public util::static_visitor<std::string>
+    struct serialize_positions
    {
        serialize_positions() {}

--- a/src/text/properties_util.cpp
+++ b/src/text/properties_util.cpp
@ -28,7 +28,7 @@

 namespace mapnik { namespace detail {

-struct property_serializer : public util::static_visitor<>
+struct property_serializer
 {
    property_serializer(std::string const& name, boost::property_tree::ptree & node)
        : name_(name),
--- a/src/transform_expression.cpp
+++ b/src/transform_expression.cpp
@ -30,7 +30,7 @@
 namespace mapnik {

 struct transform_node_to_expression_string
-    : public util::static_visitor<void>
+
 {
    std::ostringstream& os_;

--- a/src/warp.cpp
+++ b/src/warp.cpp
@ -158,7 +158,7 @@ MAPNIK_DECL void warp_image (T & target, T const& source, proj_transform const&

 namespace detail {

-struct warp_image_visitor : util::static_visitor<void>
+struct warp_image_visitor
 {
    warp_image_visitor (raster & target_raster, proj_transform const& prj_trans, box2d<double> const& source_ext,
                        double offset_x, double offset_y, unsigned mesh_size,
--- a/utils/pgsql2sqlite/sqlite.hpp
+++ b/utils/pgsql2sqlite/sqlite.hpp
@ -77,7 +77,7 @@ namespace mapnik {  namespace sqlite {

    class prepared_statement : mapnik::noncopyable
    {
-        struct binder : public mapnik::util::static_visitor<bool>
+        struct binder
        {
            binder(sqlite3_stmt * stmt, unsigned index)
                : stmt_(stmt), index_(index) {}