labeled_vertex_graph.h

/*
 * Copyright 2026 Michele Comparini
 *
 * SPDX-License-Identifier: Apache-2.0
 */
 
#ifndef GRAPHDOM_LABELED_VERTEX_GRAPH_H
#define GRAPHDOM_LABELED_VERTEX_GRAPH_H
 
#include "graph.h"
 
namespace graphdom {

    template <typename VertexType, typename VertexLabelType>
    class labeled_vertex_graph : virtual public graph<VertexType> {
        public:
            ~labeled_vertex_graph() override = default;

            [[nodiscard]] virtual const VertexLabelType& get_vertex_label(const typename graph<VertexType>::vertex_const_handle& vertex) const = 0;

            [[nodiscard]] virtual VertexLabelType& get_vertex_label(const typename graph<VertexType>::vertex_const_handle& vertex) = 0;
    };
}
 
namespace graphdom {
    template <typename VertexType, typename VertexLabelType>
    class default_vertex_labeller final {
        public:
            [[nodiscard]] constexpr VertexLabelType operator()(const VertexType&) const {
                return VertexLabelType();
            }
    };
}
 
#endif //GRAPHDOM_LABELED_VERTEX_GRAPH_H