Yexuan Xiao via Std-Proposals wrote:
> Hello everyone, I recently designed a JSON library that is suitable to
> the C++ standard, but I don’t have much experience with using
> allocators, so I need an allocator expert to help me improve it. Any
> suggestions are welcome and I hope you like it.
>
> https://storage.nykz.org/proposals/minimal-json/
>
> Here are some use cases:
>
> #include "basic_json.hpp"
> #include <string_view>
> int main()
> {
> /*
> Note: This code is for demonstration purposes only and can
> be compiled only, not be run.
> */
> // json
> using json = bizwen::json;
> using namespace std::literals;
> json j01{};
> json j02{ j01 };
> // j j03{ nullptr }; deleted
> json j04{ 1. };
> json j05{ true };
> json j06{ 1.f };
> json j07{ 1u };
> json j08{ 1l };
> json j09{ 1ll };
> json j10{ 1ull };
> json j11{ "aaa" };
> auto str = "bbb";
> json j12{ str, str + 3 };
> json j13{ str, 3 };
> json j14{ str };
> json j15{ "bbb"sv };
> // since initializer_list returns a reference to a const object,
> this method is inefficient
> // json j16{ json::array_type{ json{0}, json{1} } };
> // json j17{ json::object_type{ { "key0"s, json{ 0 } }, {
> "key1"s, json{ 1 } } } };
> json j16{ json::array{ 0, 1 } };
> json j17{ json::object{"key0"s, 0, "key1"s, 1} };
> json j18{ bizwen::basic_json_node<>{} };
> swap(j17, j18); // adl hidden friend
> j17.swap(j18);
> j17 = j18;
> std::swap(j17, j18);
> json::node_type n{ std::move(j18) };
>
> // const_slice
> using const_slice = bizwen::const_json_slice;
> const_slice c1;
> c1.empty();
> c1.array();
> c1.string();
> c1.null();
> c1.boolean();
> c1.number();
> c1.object();
> c1.array();
> c1.object();
> c1.integer();
> c1.uinteger();
> c1["key"];
> c1["key"s];
> // requires transparent comparable
> // c1["key"sv];
> c1[1];
> const_slice c2{ j17 };
> c2.swap(c1);
> std::swap(c1, c2);
> const_slice c3{ std::move(j17) };
> const_slice c4 = c3;
> const_slice c5 = std::move(c4);
> c4 = c5;
> c5 = std::move(c4);
> bool b{ c5 };
> bizwen::nulljson_t nj{ c5 };
> json::string_type const& s{ c5 };
> json::array_type const& a{ c5 };
> for (auto const& i : a)
> {
> const_slice item{ i };
> }
> json::object_type const& o{ c5 };
> for (auto const& [k, v] : o)
> {
> const_slice item{ v };
> }
> long long ll{ c5 };
> unsigned long long ull{ c5 };
>
> // slice
> using slice = bizwen::json_slice;
> slice s1{};
> slice s2{ j17 };
> const_slice c6 = s2;
> std::string str1;
> s2 = str1;
> s2 = std::string{};
> s2 = "aaa";
> s2 = std::string_view{};
> s2 = bizwen::nulljson;
> s2 = true;
> s2 = 1.;
> s2 = 1;
> s2 = 1u;
> s2 = 1ll;
> s2 = 1ull;
> s2 = n;
> s2["key"] = 1;
> }
>
>
Why should JSON be part of the C++ standard? I don't think it is
necessary or even helpful.