Introduction
bgl_named_params as named parameters in graph
Definition
Macro BOOST_BGL_ONE_PARAM_REF
There are two definitions, one is defined in the class bgl_named_params to define member methods, and the other is used as a global method
Member methods in the bgl_named_params class
#define BOOST_BGL_ONE_PARAM_REF(name, key) \
template <typename PType> \
bgl_named_params<boost::reference_wrapper<PType>, BOOST_PP_CAT(key, _t), self> \
name(PType & amp; p) const {<!-- --> \
typedef bgl_named_params<boost::reference_wrapper<PType>, BOOST_PP_CAT(key, _t), self> Params; \
return Params(boost::ref(p), *this); \
} \
global method
#define BOOST_BGL_ONE_PARAM_REF(name, key) \
template <typename PType> \
bgl_named_params<boost::reference_wrapper<PType>, BOOST_PP_CAT(key, _t)> \
name(PType & amp; p) {<!-- --> \
typedef bgl_named_params<boost::reference_wrapper<PType>, BOOST_PP_CAT(key, _t)> Params; \
return Params(boost::ref(p)); \
} \
Macro BOOST_BGL_ONE_PARAM_CREF
There are two definitions, one is defined in the class bgl_named_params to define member methods, and the other is used as a global method
Member methods in the bgl_named_params class
#define BOOST_BGL_ONE_PARAM_CREF(name, key) \
template <typename PType> \
bgl_named_params<PType, BOOST_PP_CAT(key, _t), self> \
name(const PType & amp; p) const {<!-- --> \
typedef bgl_named_params<PType, BOOST_PP_CAT(key, _t), self> Params; \
return Params(p, *this); \
} \
global method
#define BOOST_BGL_ONE_PARAM_CREF(name, key) \
template <typename PType> \
bgl_named_params<PType, BOOST_PP_CAT(key, _t)> \
name(const PType & amp; p) {<!-- --> \
typedef bgl_named_params<PType, BOOST_PP_CAT(key, _t)> Params; \
return Params(p); \
} \
Macro BOOST_BGL_DECLARE_NAMED_PARAMS
It is a series of BOOST_BGL_ONE_PARAM_CREF sets, and the defined method names include
- weight_map
The corresponding type is edge_weight_t - weight_map2
The corresponding type is edge_weight2_t - distance_map
The corresponding type is vertex_distance_t - distance_map2
The corresponding type is vertex_distance2_t - predecessor_map
The corresponding type is vertex_predecessor_t - rank_map
The corresponding type is vertex_rank_t - root_map
The corresponding type is vertex_root_t - root_vertex
The corresponding type is root_vertex_t - edge_centrality_map
The corresponding type is edge_centrality_t - centrality_map
The corresponding type is vertex_centrality_t - parity_map
The corresponding type is parity_map_t - color_map
The corresponding type is vertex_color_t - edge_color_map
The corresponding type is edge_color_t - capacity_map
The corresponding type is edge_capacity_t - residual_capacity_map
The corresponding type is edge_residual_capacity_t - reverse_edge_map
The corresponding type is edge_reverse_t - discover_time_map
The corresponding type is vertex_discover_time_t - lowpoint_map
The corresponding type is vertex_lowpoint_t - vertex_index_map
The corresponding type is vertex_index_t - vertex_index1_map
The corresponding type is vertex_index1_t - vertex_index2_map
The corresponding type is vertex_index2_t - vertex_assignment_map
The corresponding type is vertex_assignment_map_t - visitor
The corresponding type is graph_visitor_t - distance_compare
The corresponding type is distance_compare_t - distance_combine
The corresponding type is distance_combine_t - distance_inf
The corresponding type is distance_inf_t - distance_zero
The corresponding type is distance_zero_t - edge_copy
The corresponding type is edge_copy_t - vertex_copy
The corresponding type is vertex_copy_t - buffer
The corresponding type is buffer_param_t - orig_to_copy
The corresponding type is orig_to_copy_t - isomorphism_map
The corresponding type is vertex_isomorphism_t - vertex_invariant
The corresponding type is vertex_invariant_t - vertex_invariant1
The corresponding type is vertex_invariant1_t - vertex_invariant2
The corresponding type is vertex_invariant2_t - vertex_max_invariant
The corresponding type is vertex_max_invariant_t - polling
The corresponding type is polling_t - lookahead
The corresponding type is lookahead_t - in_parallel
The corresponding type is in_parallel_t - displacement_map
The corresponding type is vertex_displacement_t - attractive_force
The corresponding type is attractive_force_t - repulsive_force
The corresponding type is repulsive_force_t - force_pairs
The corresponding type is force_pairs_t - cooling
The corresponding type is cooling_t - iterations
The corresponding type is iterations_t - diameter_range
The corresponding type is diameter_range_t - learning_constant_range
The corresponding type is learning_constant_range_t - vertices_equivalent
The corresponding type is vertices_equivalent_t - edges_equivalent
The corresponding type is edges_equivalent_t - index_in_heap_map
The corresponding type is index_in_heap_map_t - max_priority_queue
The corresponding type is max_priority_queue_t
#define BOOST_BGL_DECLARE_NAMED_PARAMS \
BOOST_BGL_ONE_PARAM_CREF(weight_map, edge_weight) \
BOOST_BGL_ONE_PARAM_CREF(weight_map2, edge_weight2) \
BOOST_BGL_ONE_PARAM_CREF(distance_map, vertex_distance) \
BOOST_BGL_ONE_PARAM_CREF(distance_map2, vertex_distance2) \
BOOST_BGL_ONE_PARAM_CREF(predecessor_map, vertex_predecessor) \
BOOST_BGL_ONE_PARAM_CREF(rank_map, vertex_rank) \
BOOST_BGL_ONE_PARAM_CREF(root_map, vertex_root) \
BOOST_BGL_ONE_PARAM_CREF(root_vertex, root_vertex) \
BOOST_BGL_ONE_PARAM_CREF(edge_centrality_map, edge_centrality) \
BOOST_BGL_ONE_PARAM_CREF(centrality_map, vertex_centrality) \
BOOST_BGL_ONE_PARAM_CREF(parity_map, parity_map) \
BOOST_BGL_ONE_PARAM_CREF(color_map, vertex_color) \
BOOST_BGL_ONE_PARAM_CREF(edge_color_map, edge_color) \
BOOST_BGL_ONE_PARAM_CREF(capacity_map, edge_capacity) \
BOOST_BGL_ONE_PARAM_CREF(residual_capacity_map, edge_residual_capacity) \
BOOST_BGL_ONE_PARAM_CREF(reverse_edge_map, edge_reverse) \
BOOST_BGL_ONE_PARAM_CREF(discover_time_map, vertex_discover_time) \
BOOST_BGL_ONE_PARAM_CREF(lowpoint_map, vertex_lowpoint) \
BOOST_BGL_ONE_PARAM_CREF(vertex_index_map, vertex_index) \
BOOST_BGL_ONE_PARAM_CREF(vertex_index1_map, vertex_index1) \
BOOST_BGL_ONE_PARAM_CREF(vertex_index2_map, vertex_index2) \
BOOST_BGL_ONE_PARAM_CREF(vertex_assignment_map, vertex_assignment_map) \
BOOST_BGL_ONE_PARAM_CREF(visitor, graph_visitor) \
BOOST_BGL_ONE_PARAM_CREF(distance_compare, distance_compare) \
BOOST_BGL_ONE_PARAM_CREF(distance_combine, distance_combine) \
BOOST_BGL_ONE_PARAM_CREF(distance_inf, distance_inf) \
BOOST_BGL_ONE_PARAM_CREF(distance_zero, distance_zero) \
BOOST_BGL_ONE_PARAM_CREF(edge_copy, edge_copy) \
BOOST_BGL_ONE_PARAM_CREF(vertex_copy, vertex_copy) \
BOOST_BGL_ONE_PARAM_REF(buffer, buffer_param) \
BOOST_BGL_ONE_PARAM_CREF(orig_to_copy, orig_to_copy) \
BOOST_BGL_ONE_PARAM_CREF(isomorphism_map, vertex_isomorphism) \
BOOST_BGL_ONE_PARAM_CREF(vertex_invariant, vertex_invariant) \
BOOST_BGL_ONE_PARAM_CREF(vertex_invariant1, vertex_invariant1) \
BOOST_BGL_ONE_PARAM_CREF(vertex_invariant2, vertex_invariant2) \
BOOST_BGL_ONE_PARAM_CREF(vertex_max_invariant, vertex_max_invariant) \
BOOST_BGL_ONE_PARAM_CREF(polling, polling) \
BOOST_BGL_ONE_PARAM_CREF(lookahead, lookahead) \
BOOST_BGL_ONE_PARAM_CREF(in_parallel, in_parallel) \
BOOST_BGL_ONE_PARAM_CREF(displacement_map, vertex_displacement) \
BOOST_BGL_ONE_PARAM_CREF(attractive_force, attractive_force) \
BOOST_BGL_ONE_PARAM_CREF(repulsive_force, repulsive_force) \
BOOST_BGL_ONE_PARAM_CREF(force_pairs, force_pairs) \
BOOST_BGL_ONE_PARAM_CREF(cooling, cooling) \
BOOST_BGL_ONE_PARAM_CREF(iterations, iterations) \
BOOST_BGL_ONE_PARAM_CREF(diameter_range, diameter_range) \
BOOST_BGL_ONE_PARAM_CREF(learning_constant_range, learning_constant_range) \
BOOST_BGL_ONE_PARAM_CREF(vertices_equivalent, vertices_equivalent) \
BOOST_BGL_ONE_PARAM_CREF(edges_equivalent, edges_equivalent) \
BOOST_BGL_ONE_PARAM_CREF(index_in_heap_map, index_in_heap_map) \
BOOST_BGL_ONE_PARAM_REF(max_priority_queue, max_priority_queue)
bgl_named_params definition
template <typename T, typename Tag, typename Base = no_property>
struct bgl_named_params
{<!-- -->
typedef bgl_named_params self;
typedef Base next_type;
typedef Tag tag_type;
typedef T value_type;
bgl_named_params(T v = T()) : m_value(v) {<!-- --> }
bgl_named_params(T v, const Base & amp; b) : m_value(v), m_base(b) {<!-- --> }
T m_value;
Base m_base;
BOOST_BGL_DECLARE_NAMED_PARAMS
\t
// Duplicate
template <typename PType>
bgl_named_params<PType, vertex_color_t, self>
vertex_color_map(const PType & amp; p) const {<!-- -->return this->color_map(p);}
};
The method in bgl_named_params creates new bgl_named_params, where m_base is the old bgl_named_params, which is a nested structure
Get subitems
get_param
Specify the tag through the function template get_param to obtain the child items
template <class Tag, typename Args>
inline
const typename lookup_named_param_def<Tag, Args, param_not_found>::type & amp;
get_param(const Args & amp; p, Tag) {<!-- -->
return lookup_named_param_def<Tag, Args, param_not_found>::get(p, param_not_found());
}
Found that internally it calls the get method of lookup_named_param_def
lookup_named_param_def
There are three templates
When the first template is for a non-bgl_named_params type, the default value of the def type is returned.
template <typename Tag, typename Args, typename Def>
struct lookup_named_param_def {<!-- -->
typedef Def type;
static const Def & amp; get(const Args & amp;, const Def & amp; def) {<!-- -->return def;}
};
The second template means that when matching the bgl_named_params type, directly take the member m_value of bgl_named_params
template <typename T, typename Tag, typename Base, typename Def>
struct lookup_named_param_def<Tag, bgl_named_params<T, Tag, Base>, Def> {<!-- -->
typedef T type;
static const type & amp; get(const bgl_named_params<T, Tag, Base> & amp; p, const Def & amp;) {<!-- -->
return p.m_value;
}
};
When the third template matches the outermost bgl_named_params, the inner bgl_named_params is called nestedly.
template <typename Tag1, typename T, typename Tag, typename Base, typename Def>
struct lookup_named_param_def<Tag1, bgl_named_params<T, Tag, Base>, Def> {<!-- -->
typedef typename lookup_named_param_def<Tag1, Base, Def>::type type;
static const type & amp; get(const bgl_named_params<T, Tag, Base> & amp; p, const Def & amp; def) {<!-- -->
return lookup_named_param_def<Tag1, Base, Def>::get(p.m_base, def);
}
};