
.. _program_listing_file_zeem_xpath.hpp:

Program Listing for File xpath.hpp
==================================

|exhale_lsh| :ref:`Return to documentation for file <file_zeem_xpath.hpp>` (``zeem/xpath.hpp``)

.. |exhale_lsh| unicode:: U+021B0 .. UPWARDS ARROW WITH TIP LEFTWARDS

.. code-block:: cpp

   /*-
    * SPDX-License-Identifier: BSD-2-Clause
    *
    * Copyright (c) 2024 Maarten L. Hekkelman
    *
    * Redistribution and use in source and binary forms, with or without
    * modification, are permitted provided that the following conditions are met:
    *
    * 1. Redistributions of source code must retain the above copyright notice, this
    *    list of conditions and the following disclaimer
    * 2. Redistributions in binary form must reproduce the above copyright notice,
    *    this list of conditions and the following disclaimer in the documentation
    *    and/or other materials provided with the distribution.
    *
    * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
    * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
    * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
    * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
    * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
    * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
    * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
    * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
    * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
    * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
    */
   
   #pragma once
   
   
   #include <memory>
   #include <string>
   #include <string_view>
   #include <type_traits>
   #include <vector>
   
   namespace zeem
   {
   
   class node;
   
   // --------------------------------------------------------------------
   
   
   class context final
   {
     public:
       context();
   
       context(const context &ctxt) = default;
   
       context(context &&ctxt) noexcept
       {
           std::swap(m_impl, ctxt.m_impl);
       }
   
       context &operator=(context ctxt)
       {
           std::swap(m_impl, ctxt.m_impl);
           return *this;
       }
   
       void set(const std::string &name, std::string value);
   
       void set(const std::string &name, double value);
   
       template <typename T>
           requires std::is_same_v<T, std::string> or std::is_same_v<T, double>
       T get(std::string name);
   
     private:
       friend class xpath;
   
       std::shared_ptr<struct context_imp> m_impl;
   };
   
   // --------------------------------------------------------------------
   
   
   class xpath final
   {
     public:
       explicit xpath(std::string_view path);
   
       xpath(const xpath &rhs) = default;
   
       xpath(xpath &&rhs) noexcept
       {
           std::swap(m_impl, rhs.m_impl);
       }
   
       xpath &operator=(xpath xp)
       {
           std::swap(m_impl, xp.m_impl);
           return *this;
       }
   
   
       template <typename T>
       [[nodiscard]] std::vector<T *> evaluate(const node &root, const context &ctxt = {}) const;
   
       bool matches(const node *n, const context &ctxt = {}) const;
   
     private:
       std::shared_ptr<class expression> m_impl;
   };
   
   } // namespace zeem
