cpp-json/include/json/json.hpp

//
//  json.hpp
//  json
//
//  Created by Sam Jaffe on 1/30/16.
//  Copyright © 2016 Sam Jaffe. All rights reserved.
//

#pragma once

#include "json_common.hpp"
#include "variant/variant.hpp"

#include <map>
#include <utility>
#include <vector>

#define JSON_TYPE_LIST                                                         \
  X(object)                                                                    \
  X(array)                                                                     \
  X(string)                                                                    \
  X(double)                                                                    \
  X(int)                                                                       \
  X(uint)                                                                      \
  X(bool)

namespace json {
  class value;

  template <> void helper::parse_numeric(value & json, char const *& data);

  namespace parser {
    void parse(value &, char const *);
  }

  class value {
  public:
    using object_jt = std::map<std::string, value>;
    using array_jt = std::vector<value>;
    using string_jt = json::string_jt;
    using double_jt = json::double_jt;
    using int_jt = json::int_jt;
    using uint_jt = json::uint_jt;
    using bool_jt = json::bool_jt;

  private:
    static const value null_value;

    using data_t = variant<object_jt, array_jt, string_jt, double_jt, int_jt,
                           uint_jt, bool_jt>;
    data_t data;

  public:
#define X(type)                                                                \
  bool is_##type() const { return data.is<type##_jt>(); }
    JSON_TYPE_LIST
#undef X
    bool is_null() const { return !data.valid(); }

    value() = default;
    value(value const &) = default;
    value(value &&) = default;
    value & operator=(value const &) = default;
    value & operator=(value &&) = default;
#define X(type)                                                                \
  value(type##_jt val) { data.set<type##_jt>(std::move(val)); }
    JSON_TYPE_LIST
#undef X
#define X(type)                                                                \
  value & operator=(type##_jt val) {                                           \
    data.set<type##_jt>(std::move(val));                                       \
    return *this;                                                              \
  }
    JSON_TYPE_LIST
#undef X

    void parse(char const * data);
    void parse(std::string const & str);
    void parse(std::istream & in);

    void clear() { data = data_t(); }

    value & operator[](const size_t idx);
    value const & operator[](const size_t idx) const;
    value & operator[](std::string const & key);
    value const & operator[](std::string const & key) const;

    string_jt const & as_string() const;
    double_jt as_double() const;
    int_jt as_int() const;
    uint_jt as_uint() const;
    bool_jt as_bool() const;

    operator string_jt const &() const { return as_string(); }
    operator double_jt() const { return as_double(); }
    operator int_jt() const { return as_int(); }
    operator uint_jt() const { return as_uint(); }
    operator bool_jt() const { return as_bool(); }
  };
#undef JSON_TYPE_LIST
  namespace parser {
    void parse(json::value &, char const *);
    void parse(json::value & json, std::istream & in);
  }
}