bump

extractor PR with clangcl tweaks

.clangd

@@ -25,6 +25,7 @@ CompileFlags:
 Diagnostics:
     Suppress:
         - pp_including_mainfile_in_preamble
+        - unused-includes
 ---
 # Amalgamated files that require or partly define an implementation
 If:

.github/workflows/cifuzz.yml

@@ -17,7 +17,7 @@ jobs:
         fuzz-seconds: 600
         dry-run: false
     - name: Upload Crash
-      uses: actions/upload-artifact@v1
+      uses: actions/upload-artifact@v3
       if: failure() && steps.build.outcome == 'success'
       with:
         name: artifacts

.github/workflows/fix-trailing-whitespace.yml

@@ -24,7 +24,7 @@ jobs:
              echo "no trailing whitespace found, good!"
           fi
       - name: Archive whitespace patch
-        uses: actions/upload-artifact@v2
+        uses: actions/upload-artifact@v3
         if: always()
         with:
           name: whitespace-patch

.github/workflows/vs17-clang-ci.yml

@@ -13,15 +13,15 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          - {gen: Visual Studio 17 2022, arch: x64, build_type: Debug}
-          - {gen: Visual Studio 17 2022, arch: x64, build_type: Release}
-          - {gen: Visual Studio 17 2022, arch: x64, build_type: RelWithDebInfo}
+          - {gen: Visual Studio 17 2022, arch: x64, build_type: Debug, cxx: 17}
+          - {gen: Visual Studio 17 2022, arch: x64, build_type: Debug, cxx: 20}
+          - {gen: Visual Studio 17 2022, arch: x64, build_type: Release, cxx: 17}
     steps:
     - name: checkout
       uses: actions/checkout@v4
     - name: Configure
       run: |
-        cmake -G "${{matrix.gen}}" -A ${{matrix.arch}}  -T ClangCL -DSIMDJSON_DEVELOPER_MODE=ON -DSIMDJSON_COMPETITION=OFF -B build
+        cmake -G "${{matrix.gen}}" -A ${{matrix.arch}} -DSIMDJSON_CXX_STANDARD=${{matrix.cxx}} -T ClangCL -DSIMDJSON_DEVELOPER_MODE=ON -DSIMDJSON_COMPETITION=OFF -B build
     - name: Build
       run: cmake --build build --config ${{matrix.build_type}} --verbose
     - name: Run tests

.vscode/settings.json

@@ -110,5 +110,10 @@
         "semaphore": "cpp",
         "stop_token": "cpp",
         "cfenv": "cpp"
+    },
+    "cmake.configureSettings": {
+        "CMAKE_EXPORT_COMPILE_COMMANDS": "YES",
+        "SIMDJSON_DEVELOPER_MODE": "ON",
+        "SIMDJSON_SINGLEHEADER": "OFF"
     }
 }

CMakeLists.txt

@@ -3,7 +3,7 @@ cmake_minimum_required(VERSION 3.14)
 project(
     simdjson
     # The version number is modified by tools/release.py
-    VERSION 3.10.0
+    VERSION 3.10.1
     DESCRIPTION "Parsing gigabytes of JSON per second"
     HOMEPAGE_URL "https://simdjson.org/"
     LANGUAGES CXX C
@@ -23,7 +23,11 @@ string(
 set(SIMDJSON_LIB_VERSION "23.0.0" CACHE STRING "simdjson library version")
 set(SIMDJSON_LIB_SOVERSION "23" CACHE STRING "simdjson library soversion")
 
-option(SIMDJSON_BUILD_STATIC_LIB "Build simdjson_static library along with simdjson" OFF)
+option(SIMDJSON_BUILD_STATIC_LIB "Build simdjson_static library along with simdjson (only makes sense if BUILD_SHARED_LIBS=ON)" OFF)
+if(SIMDJSON_BUILD_STATIC_LIB AND NOT BUILD_SHARED_LIBS)
+  message(WARNING "SIMDJSON_BUILD_STATIC_LIB only makes sense if BUILD_SHARED_LIBS is set to ON")
+  message(WARNING "You might be building and installing a two identical static libraries.")
+endif()
 
 option(SIMDJSON_ENABLE_THREADS "Link with thread support" ON)
 
@@ -51,6 +55,7 @@ endif()
 if(is_top_project)
   option(SIMDJSON_DEVELOPER_MODE "Enable targets for developing simdjson" OFF)
   option(BUILD_SHARED_LIBS "Build simdjson as a shared library" OFF)
+  option(SIMDJSON_SINGLEHEADER "Disable singleheader generation" ON)
 endif()
 
 include(cmake/handle-deprecations.cmake)
@@ -155,11 +160,13 @@ endif()
 include(CMakePackageConfigHelpers)
 include(GNUInstallDirs)
 
-install(
-    FILES singleheader/simdjson.h
-    DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}"
-    COMPONENT simdjson_Development
-)
+if(SIMDJSON_SINGLEHEADER)
+  install(
+      FILES singleheader/simdjson.h
+      DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}"
+      COMPONENT simdjson_Development
+  )
+endif()
 
 install(
     TARGETS simdjson
@@ -203,6 +210,7 @@ if(SIMDJSON_BUILD_STATIC_LIB)
       TARGETS simdjson_static
       EXPORT simdjson_staticTargets
       ARCHIVE COMPONENT simdjson_Development
+      INCLUDES DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}"
   )
   install(
       EXPORT simdjson_staticTargets
@@ -286,8 +294,9 @@ add_subdirectory(tools)  ## This needs to be before tests because of cxxopts
 # most of the data has been moved to https://github.com/simdjson/simdjson-data
 add_subdirectory(jsonexamples)
 
-
+if(SIMDJSON_SINGLEHEADER)
 add_subdirectory(singleheader)
+endif()
 
 
 

Doxyfile

@@ -38,7 +38,7 @@ PROJECT_NAME           = simdjson
 # could be handy for archiving the generated documentation or if some version
 # control system is used.
 
-PROJECT_NUMBER         = "3.10.0"
+PROJECT_NUMBER         = "3.10.1"
 
 # Using the PROJECT_BRIEF tag one can provide an optional one line description
 # for a project that appears at the top of each page and should give viewer a

README.md

@@ -201,8 +201,8 @@ For the video inclined, <br />
 Funding
 -------
 
-The work is supported by the Natural Sciences and Engineering Research Council of Canada under grant
-number RGPIN-2017-03910.
+The work is supported by the Natural Sciences and Engineering Research Council of Canada under grants
+RGPIN-2017-03910 and RGPIN-2024-03787.
 
 [license]: LICENSE
 [license img]: https://img.shields.io/badge/License-Apache%202-blue.svg

benchmark/kostya/simdjson_ondemand.h

@@ -24,6 +24,35 @@ struct simdjson_ondemand {
 
 BENCHMARK_TEMPLATE(kostya, simdjson_ondemand)->UseManualTime();
 
+
+#if SIMDJSON_SUPPORTS_EXTRACT
+using namespace simdjson::ondemand;
+
+struct simdjson_ondemand_extract {
+  static constexpr diff_flags DiffFlags = diff_flags::NONE;
+
+  ondemand::parser parser{};
+
+  bool run(simdjson::padded_string &json, std::vector<point> &result) {
+    auto doc = parser.iterate(json);
+    for (ondemand::object object_point : doc.find_field("coordinates")) {
+      point p;
+      auto error = object_point.extract(
+        to{"x", p.x},
+        to{"y", p.y},
+        to{"z", p.z}
+      );
+      if(error) { return false; }
+      result.push_back(p);
+    }
+    return true;
+  }
+};
+
+BENCHMARK_TEMPLATE(kostya, simdjson_ondemand_extract)->UseManualTime();
+
+#endif // SIMDJSON_SUPPORTS_EXTRACT
+
 } // namespace kostya
 
 #endif // SIMDJSON_EXCEPTIONS

benchmark/partial_tweets/simdjson_ondemand.h

@@ -9,7 +9,7 @@ namespace partial_tweets {
 using namespace simdjson;
 
 struct simdjson_ondemand {
-  using StringType=std::string_view;
+  using StringType = std::string_view;
 
   ondemand::parser parser{};
 
@@ -43,6 +43,47 @@ struct simdjson_ondemand {
 
 BENCHMARK_TEMPLATE(partial_tweets, simdjson_ondemand)->UseManualTime();
 
+
+#if SIMDJSON_SUPPORTS_EXTRACT
+using namespace simdjson::ondemand;
+
+struct simdjson_ondemand_extract {
+  using StringType = std::string_view;
+  ondemand::parser parser{};
+  bool run(simdjson::padded_string &json, std::vector<tweet<std::string_view>> &result) {
+    // Walk the document, parsing the tweets as we go
+    auto doc = parser.iterate(json);
+    for (ondemand::object tweet_object : doc.find_field("statuses")) {
+      tweet<std::string_view> t;
+      auto error = tweet_object.extract(
+        to{"created_at", t.created_at},
+        to{"id", t.id},
+        to{"text", t.result},
+        to{"in_reply_to_status_id", [&t](auto val) {
+          if(val.is_null()) {
+            t.in_reply_to_status_id = 0;
+          } else {
+            t.in_reply_to_status_id = val;
+          }
+         }},
+        to{"user", sub{
+          to{"id", t.user.id},
+          to{"screen_name", t.user.screen_name},
+        }},
+        to{"retweet_count", t.retweet_count},
+        to{"favorite_count", t.favorite_count});
+        if(error) { return false; }
+        result.push_back(t);
+    }
+    return true;
+  }
+};
+
+BENCHMARK_TEMPLATE(partial_tweets, simdjson_ondemand_extract)->UseManualTime();
+
+
+#endif
+
 } // namespace partial_tweets
 
 #endif // SIMDJSON_EXCEPTIONS

doc/parse_many.md

@@ -125,7 +125,7 @@ Whitespace Characters:
 - **Nothing**
 
 Some official formats **(non-exhaustive list)**:
-- [Newline-Delimited JSON (NDJSON)](http://ndjson.org/)
+- [Newline-Delimited JSON (NDJSON)](https://github.com/ndjson/ndjson-spec)
 - [JSON lines (JSONL)](http://jsonlines.org/)
 - [Record separator-delimited JSON (RFC 7464)](https://tools.ietf.org/html/rfc7464) <- Not supported by JsonStream!
 - [More on Wikipedia...](https://en.wikipedia.org/wiki/JSON_streaming)

include/simdjson/common_defs.h

@@ -50,6 +50,8 @@ double from_chars(const char *first, const char* end) noexcept;
 #define SIMDJSON_ISALIGNED_N(ptr, n) (((uintptr_t)(ptr) & ((n)-1)) == 0)
 
 #if SIMDJSON_REGULAR_VISUAL_STUDIO
+  // We could use [[deprecated]] but it requires C++14
+  #define simdjson_deprecated __declspec(deprecated)
 
   #define simdjson_really_inline __forceinline
   #define simdjson_never_inline __declspec(noinline)
@@ -88,6 +90,8 @@ double from_chars(const char *first, const char* end) noexcept;
   #define SIMDJSON_POP_DISABLE_UNUSED_WARNINGS
 
 #else // SIMDJSON_REGULAR_VISUAL_STUDIO
+  // We could use [[deprecated]] but it requires C++14
+  #define simdjson_deprecated __attribute__((deprecated))
 
   #define simdjson_really_inline inline __attribute__((always_inline))
   #define simdjson_never_inline inline __attribute__((noinline))

include/simdjson/compiler_check.h

@@ -50,4 +50,18 @@
 #endif
 #endif
 
+#ifdef __has_include
+#if __has_include(<version>)
+#include <version>
+#endif
+#endif
+
+
+
+#if defined(__cpp_concepts)
+#define SIMDJSON_SUPPORTS_EXTRACT 1
+#else
+#define SIMDJSON_SUPPORTS_EXTRACT 0
+#endif
+
 #endif // SIMDJSON_COMPILER_CHECK_H

include/simdjson/fallback/bitmanipulation.h

@@ -9,7 +9,7 @@ namespace simdjson {
 namespace fallback {
 namespace {
 
-#if defined(_MSC_VER) && !defined(_M_ARM64) && !defined(_M_X64)
+#if SIMDJSON_REGULAR_VISUAL_STUDIO && !defined(_M_ARM64) && !defined(_M_X64)
 static inline unsigned char _BitScanForward64(unsigned long* ret, uint64_t x) {
   unsigned long x0 = (unsigned long)x, top, bottom;
   _BitScanForward(&top, (unsigned long)(x >> 32));
@@ -28,7 +28,7 @@ static unsigned char _BitScanReverse64(unsigned long* ret, uint64_t x) {
 
 /* result might be undefined when input_num is zero */
 simdjson_inline int leading_zeroes(uint64_t input_num) {
-#ifdef _MSC_VER
+#ifdef SIMDJSON_REGULAR_VISUAL_STUDIO
   unsigned long leading_zero = 0;
   // Search the mask data from most significant bit (MSB)
   // to least significant bit (LSB) for a set bit (1).
@@ -38,7 +38,7 @@ simdjson_inline int leading_zeroes(uint64_t input_num) {
     return 64;
 #else
   return __builtin_clzll(input_num);
-#endif// _MSC_VER
+#endif// SIMDJSON_REGULAR_VISUAL_STUDIO
 }
 
 } // unnamed namespace

include/simdjson/generic/ondemand/document-inl.h

@@ -3,16 +3,14 @@
 #ifndef SIMDJSON_CONDITIONAL_INCLUDE
 #define SIMDJSON_GENERIC_ONDEMAND_DOCUMENT_INL_H
 #include "simdjson/generic/ondemand/base.h"
-#include "simdjson/generic/ondemand/array-inl.h"
 #include "simdjson/generic/ondemand/array_iterator.h"
 #include "simdjson/generic/ondemand/document.h"
-#include "simdjson/generic/ondemand/json_iterator-inl.h"
-#include "simdjson/generic/ondemand/json_path_to_pointer_conversion.h"
-#include "simdjson/generic/ondemand/json_path_to_pointer_conversion-inl.h"
 #include "simdjson/generic/ondemand/json_type.h"
-#include "simdjson/generic/ondemand/object-inl.h"
 #include "simdjson/generic/ondemand/raw_json_string.h"
 #include "simdjson/generic/ondemand/value.h"
+#include "simdjson/generic/ondemand/array-inl.h"
+#include "simdjson/generic/ondemand/json_iterator-inl.h"
+#include "simdjson/generic/ondemand/object-inl.h"
 #include "simdjson/generic/ondemand/value_iterator-inl.h"
 #endif // SIMDJSON_CONDITIONAL_INCLUDE
 
@@ -167,24 +165,26 @@ template<> simdjson_inline simdjson_result<int64_t> document::get() & noexcept {
 template<> simdjson_inline simdjson_result<bool> document::get() & noexcept { return get_bool(); }
 template<> simdjson_inline simdjson_result<value> document::get() & noexcept { return get_value(); }
 
-template<> simdjson_inline simdjson_result<raw_json_string> document::get() && noexcept { return get_raw_json_string(); }
-template<> simdjson_inline simdjson_result<std::string_view> document::get() && noexcept { return get_string(false); }
-template<> simdjson_inline simdjson_result<double> document::get() && noexcept { return std::forward<document>(*this).get_double(); }
-template<> simdjson_inline simdjson_result<uint64_t> document::get() && noexcept { return std::forward<document>(*this).get_uint64(); }
-template<> simdjson_inline simdjson_result<int64_t> document::get() && noexcept { return std::forward<document>(*this).get_int64(); }
-template<> simdjson_inline simdjson_result<bool> document::get() && noexcept { return std::forward<document>(*this).get_bool(); }
-template<> simdjson_inline simdjson_result<value> document::get() && noexcept { return get_value(); }
+template<> simdjson_deprecated simdjson_inline simdjson_result<raw_json_string> document::get() && noexcept { return get_raw_json_string(); }
+template<> simdjson_deprecated simdjson_inline simdjson_result<std::string_view> document::get() && noexcept { return get_string(false); }
+template<> simdjson_deprecated simdjson_inline simdjson_result<double> document::get() && noexcept { return std::forward<document>(*this).get_double(); }
+template<> simdjson_deprecated simdjson_inline simdjson_result<uint64_t> document::get() && noexcept { return std::forward<document>(*this).get_uint64(); }
+template<> simdjson_deprecated simdjson_inline simdjson_result<int64_t> document::get() && noexcept { return std::forward<document>(*this).get_int64(); }
+template<> simdjson_deprecated simdjson_inline simdjson_result<bool> document::get() && noexcept { return std::forward<document>(*this).get_bool(); }
+template<> simdjson_deprecated simdjson_inline simdjson_result<value> document::get() && noexcept { return get_value(); }
 
 template<typename T> simdjson_inline error_code document::get(T &out) & noexcept {
   return get<T>().get(out);
 }
-template<typename T> simdjson_inline error_code document::get(T &out) && noexcept {
+template<typename T> simdjson_deprecated simdjson_inline error_code document::get(T &out) && noexcept {
   return std::forward<document>(*this).get<T>().get(out);
 }
 
 #if SIMDJSON_EXCEPTIONS
 template <class T>
-simdjson_inline document::operator T() noexcept(false) { return get<T>(); }
+simdjson_deprecated simdjson_inline document::operator T() && noexcept(false) { return get<T>(); }
+template <class T>
+simdjson_inline document::operator T() & noexcept(false) { return get<T>(); }
 simdjson_inline document::operator array() & noexcept(false) { return get_array(); }
 simdjson_inline document::operator object() & noexcept(false) { return get_object(); }
 simdjson_inline document::operator uint64_t() noexcept(false) { return get_uint64(); }
@@ -471,7 +471,7 @@ simdjson_inline simdjson_result<T> simdjson_result<SIMDJSON_IMPLEMENTATION::onde
   return first.get<T>();
 }
 template<typename T>
-simdjson_inline simdjson_result<T> simdjson_result<SIMDJSON_IMPLEMENTATION::ondemand::document>::get() && noexcept {
+simdjson_deprecated simdjson_inline simdjson_result<T> simdjson_result<SIMDJSON_IMPLEMENTATION::ondemand::document>::get() && noexcept {
   if (error()) { return error(); }
   return std::forward<SIMDJSON_IMPLEMENTATION::ondemand::document>(first).get<T>();
 }
@@ -487,7 +487,7 @@ simdjson_inline error_code simdjson_result<SIMDJSON_IMPLEMENTATION::ondemand::do
 }
 
 template<> simdjson_inline simdjson_result<SIMDJSON_IMPLEMENTATION::ondemand::document> simdjson_result<SIMDJSON_IMPLEMENTATION::ondemand::document>::get<SIMDJSON_IMPLEMENTATION::ondemand::document>() & noexcept = delete;
-template<> simdjson_inline simdjson_result<SIMDJSON_IMPLEMENTATION::ondemand::document> simdjson_result<SIMDJSON_IMPLEMENTATION::ondemand::document>::get<SIMDJSON_IMPLEMENTATION::ondemand::document>() && noexcept {
+template<> simdjson_deprecated simdjson_inline simdjson_result<SIMDJSON_IMPLEMENTATION::ondemand::document> simdjson_result<SIMDJSON_IMPLEMENTATION::ondemand::document>::get<SIMDJSON_IMPLEMENTATION::ondemand::document>() && noexcept {
   if (error()) { return error(); }
   return std::forward<SIMDJSON_IMPLEMENTATION::ondemand::document>(first);
 }

include/simdjson/generic/ondemand/document.h

@@ -188,7 +188,7 @@ public:
       " You may also add support for custom types, see our documentation.");
   }
   /** @overload template<typename T> simdjson_result<T> get() & noexcept */
-  template<typename T> simdjson_inline simdjson_result<T> get() && noexcept {
+  template<typename T> simdjson_deprecated simdjson_inline simdjson_result<T> get() && noexcept {
     // Unless the simdjson library or the user provides an inline implementation, calling this method should
     // immediately fail.
     static_assert(!sizeof(T), "The get method with given type is not implemented by the simdjson library. "
@@ -211,7 +211,7 @@ public:
    */
   template<typename T> simdjson_inline error_code get(T &out) & noexcept;
   /** @overload template<typename T> error_code get(T &out) & noexcept */
-  template<typename T> simdjson_inline error_code get(T &out) && noexcept;
+  template<typename T> simdjson_deprecated simdjson_inline error_code get(T &out) && noexcept;
 
 #if SIMDJSON_EXCEPTIONS
   /**
@@ -224,7 +224,10 @@ public:
    * @returns An instance of type T
    */
   template <class T>
-  explicit simdjson_inline operator T() noexcept(false);
+  explicit simdjson_inline operator T() & noexcept(false);
+  template <class T>
+  explicit simdjson_deprecated simdjson_inline operator T() && noexcept(false);
+
   /**
    * Cast this JSON value to an array.
    *
@@ -790,7 +793,7 @@ public:
   simdjson_inline simdjson_result<bool> is_null() noexcept;
 
   template<typename T> simdjson_inline simdjson_result<T> get() & noexcept;
-  template<typename T> simdjson_inline simdjson_result<T> get() && noexcept;
+  template<typename T> simdjson_deprecated simdjson_inline simdjson_result<T> get() && noexcept;
 
   template<typename T> simdjson_inline error_code get(T &out) & noexcept;
   template<typename T> simdjson_inline error_code get(T &out) && noexcept;

include/simdjson/generic/ondemand/document_stream.h

@@ -316,7 +316,7 @@ private:
   friend class document;
   friend class json_iterator;
   friend struct simdjson_result<ondemand::document_stream>;
-  friend struct internal::simdjson_result_base<ondemand::document_stream>;
+  friend struct simdjson::internal::simdjson_result_base<ondemand::document_stream>;
 };  // document_stream
 
 } // namespace ondemand

include/simdjson/generic/ondemand/json_path_to_pointer_conversion-inl.h

@@ -1,67 +0,0 @@
-#pragma once
-
-#ifndef SIMDJSON_ONDEMAND_GENERIC_JSON_PATH_TO_POINTER_CONVERSION_INL_H
-#define SIMDJSON_ONDEMAND_GENERIC_JSON_PATH_TO_POINTER_CONVERSION_INL_H
-
-#ifndef SIMDJSON_CONDITIONAL_INCLUDE
-#define SIMDJSON_GENERIC_ONDEMAND_JSON_PATH_TO_POINTER_CONVERSION_INL_H
-#include "simdjson/generic/ondemand/json_path_to_pointer_conversion.h"
-#endif // SIMDJSON_CONDITIONAL_INCLUDE
-
-namespace simdjson {
-namespace SIMDJSON_IMPLEMENTATION {}
-namespace ondemand {
-
-simdjson_inline std::string json_path_to_pointer_conversion(std::string_view json_path) {
-  if (json_path.empty() || (json_path.front() != '.' && json_path.front() != '[') {
-    return "-1"; // Sentinel value to be handled as an error by the caller.
-  }
-
-  std::string result;
-  // Reserve space to reduce allocations, adjusting for potential increases due
-  // to escaping.
-  result.reserve(json_path.size() * 2);
-
-  // Skip the initial '.' as it's assumed every path starts with it.
-  size_t i = 0;
-
-  while (i < json_path.length()) {
-    if (json_path[i] == '.') {
-      result += '/';
-    } else if (json_path[i] == '[') {
-      result += '/';
-      ++i; // Move past the '['
-      while (i < json_path.length() && json_path[i] != ']') {
-        if (json_path[i] == '~') {
-          result += "~0";
-        } else if (json_path[i] == '/') {
-          result += "~1";
-        } else {
-          result += json_path[i];
-        }
-        ++i;
-      }
-      if (i == json_path.length() || json_path[i] != ']') {
-        return "-1"; // Returning sentinel value that will be handled as an error by the caller
-      }
-    } else {
-      if (json_path[i] == '~') {
-        result += "~0";
-      } else if (json_path[i] == '/') {
-        result += "~1";
-      } else {
-        result += json_path[i];
-      }
-    }
-    ++i;
-  }
-
-  return simdjson_result<std::string>(result);
-}
-
-
-} // namespace ondemand
-} // namespace SIMDJSON_IMPLEMENTATION
-} // namespace simdjson
-
-#endif // SIMDJSON_ONDEMAND_GENERIC_JSON_PATH_TO_POINTER_CONVERSION_INL_H

include/simdjson/generic/ondemand/json_path_to_pointer_conversion.h

@@ -1,22 +0,0 @@
-#pragma once
-
-#ifndef SIMDJSON_ONDEMAND_GENERIC_JSON_PATH_TO_POINTER_CONVERSION_H
-#define SIMDJSON_ONDEMAND_GENERIC_JSON_PATH_TO_POINTER_CONVERSION_H
-
-namespace simdjson {
-namespace SIMDJSON_IMPLEMENTATION {
-namespace internal {
-
-/**
- * Converts JSONPath to JSON Pointer.
- * @param json_path The JSONPath string to be converted.
- * @return A string containing the equivalent JSON Pointer.
- * @throws simdjson_error If the conversion fails.
- */
-simdjson_inline std::string json_path_to_pointer_conversion(std::string_view json_path);
-
-} // namespace internal
-} // namespace SIMDJSON_IMPLEMENTATION
-} // namespace simdjson
-
-#endif // SIMDJSON_JSON_PATH_TO_POINTER_CONVERSION_H

include/simdjson/generic/ondemand/object-inl.h

@@ -15,6 +15,141 @@ namespace simdjson {
 namespace SIMDJSON_IMPLEMENTATION {
 namespace ondemand {
 
+
+#if SIMDJSON_SUPPORTS_EXTRACT
+
+
+#if SIMDJSON_REGULAR_VISUAL_STUDIO
+template <endpoint ...Funcs>
+simdjson_inline error_code object::extract(Funcs&&... endpoints) {
+  return iter.on_field_raw([&, eps = std::make_tuple(std::forward<Funcs>(endpoints)...)](auto field_key, error_code& error) mutable {
+    std::apply([&](auto &...endpoints) {
+       std::ignore = ((field_key.unsafe_is_equal(endpoints.key()) ? (error = endpoints(value(iter.child()))) == SUCCESS : true) && ...);
+    }, eps);
+    if (error) {
+      return true;
+    }
+    return false;
+  });
+}
+#else
+template <endpoint ...Funcs>
+simdjson_inline error_code object::extract(Funcs&&... endpoints) noexcept((nothrow_endpoint<Funcs> && ...)) {
+  return iter.on_field_raw([&](auto field_key, error_code& error) noexcept((nothrow_endpoint<Funcs> && ...)) {
+    std::ignore = ((field_key.unsafe_is_equal(endpoints.key()) ? (error = endpoints(value(iter.child()))) == SUCCESS : true) && ...);
+    if (error) {
+      return true;
+    }
+    return false;
+  });
+}
+#endif
+
+template <typename T>
+struct to {
+private:
+  T *pointer;
+  std::string_view m_key;
+
+public:
+  constexpr explicit(false)
+      to(std::string_view const inp_key, T &obj_ref) noexcept
+      : pointer{std::addressof(obj_ref)}, m_key{inp_key} {}
+
+  constexpr to(to const &) = default;
+  constexpr to(to &&) noexcept = default;
+  constexpr to &operator=(to const &) = default;
+  constexpr to &operator=(to &&) noexcept = default;
+  constexpr ~to() = default;
+
+  [[nodiscard]] constexpr std::string_view key() const noexcept {
+    return m_key;
+  }
+
+  [[nodiscard]] constexpr error_code operator()(simdjson_result<value> val) noexcept(
+      std::is_nothrow_assignable_v<T, simdjson_result<value>>) {
+    return val.get<T>(*pointer);
+  }
+};
+
+template <typename Func>
+  requires(std::is_invocable_v<Func, simdjson_result<value>>)
+struct to<Func> {
+private:
+  Func func;
+  std::string_view m_key;
+
+public:
+  constexpr explicit(false)
+      to(std::string_view const inp_key,
+         Func &&inp_func) noexcept(std::is_nothrow_copy_assignable_v<Func>)
+      : func{std::forward<Func>(inp_func)}, m_key{inp_key} {}
+
+  constexpr to(to const &) = default;
+  constexpr to(to &&) noexcept = default;
+  constexpr to& operator=(to const &) = default;
+  constexpr to& operator=(to &&) noexcept = default;
+  constexpr ~to() = default;
+
+  [[nodiscard]] constexpr std::string_view key() const noexcept {
+    return m_key;
+  }
+
+  [[nodiscard]] constexpr error_code operator()(simdjson_result<value> val) noexcept(
+      std::is_nothrow_invocable_v<Func, simdjson_result<value>>) {
+    if constexpr (std::is_invocable_r_v<error_code, Func, simdjson_result<value>>) {
+      return func(val);
+    } else {
+      static_cast<void>(func(val));
+      return SUCCESS;
+    }
+  }
+};
+
+template <typename Func>
+  requires(std::is_invocable_v<Func, simdjson_result<value>>)
+to(std::string_view, Func &&) -> to<Func>;
+
+template <typename T>
+to(std::string_view, T&) -> to<T>;
+
+template <endpoint... Tos>
+struct sub {
+private:
+  using tuple_type = std::tuple<Tos...>;
+  tuple_type tos;
+
+public:
+
+  // double templating to make perfect forwarding work
+  template <typename ...T>
+    requires ((std::same_as<T, Tos> && ...))
+  explicit constexpr sub(T&&...inp_tos) noexcept(std::is_nothrow_constructible_v<tuple_type, T...>)
+      : tos{std::forward<T>(inp_tos)...} {}
+
+  constexpr sub(sub const &) = default;
+  constexpr sub(sub &&) noexcept = default;
+  constexpr sub &operator=(sub const &) = default;
+  constexpr sub &operator=(sub &&) = default;
+  constexpr ~sub() = default;
+
+  [[nodiscard]] constexpr error_code operator()(simdjson_result<value> val) noexcept((nothrow_endpoint<Tos> && ...)) {
+    object obj;
+    if (auto const err = val.get_object().get(obj); err) {
+      return err;
+    }
+    return std::apply([&obj]<typename... T>(T &&...app_tos) {
+      return obj.extract(std::forward<T>(app_tos)...);
+    }, tos);
+  }
+};
+
+template <endpoint... Tos>
+sub(Tos&&...) -> sub<Tos...>;
+
+#endif
+
+
 simdjson_inline simdjson_result<value> object::find_field_unordered(const std::string_view key) & noexcept {
   bool has_value;
   SIMDJSON_TRY( iter.find_field_unordered_raw(key).get(has_value) );

include/simdjson/generic/ondemand/object.h

@@ -11,6 +11,19 @@ namespace simdjson {
 namespace SIMDJSON_IMPLEMENTATION {
 namespace ondemand {
 
+#if SIMDJSON_SUPPORTS_EXTRACT
+
+template <typename T>
+concept endpoint = std::is_invocable_r_v<error_code, T, simdjson_result<value>> &&
+                   std::is_copy_constructible_v<T> && requires(T to) {
+                     { to.key() } noexcept -> std::convertible_to<std::string_view>;
+                   };
+
+template <typename T>
+concept nothrow_endpoint = endpoint<T> && std::is_nothrow_invocable_r_v<error_code, T, simdjson_result<value>>;
+
+#endif
+
 /**
  * A forward-only JSON object field iterator.
  */
@@ -65,6 +78,21 @@ public:
   /** @overload simdjson_inline simdjson_result<value> find_field(std::string_view key) & noexcept; */
   simdjson_inline simdjson_result<value> find_field(std::string_view key) && noexcept;
 
+#if SIMDJSON_SUPPORTS_EXTRACT
+  /**
+   * Extract all the fields in one go
+   * Funcs are invocables that take a simdjson_result<value> as input.
+   */
+  template <endpoint ...Funcs>
+  simdjson_inline error_code extract(Funcs&&... endpoints)
+#ifndef SIMDJSON_REGULAR_VISUAL_STUDIO // msvc thinks noexcept is not the same in definition
+ noexcept((nothrow_endpoint<Funcs> && ...))
+#endif
+ ;
+#endif
+
+
+
   /**
    * Look up a field by name on an object, without regard to key order.
    *

include/simdjson/generic/ondemand/parser.h

@@ -340,7 +340,7 @@ public:
 
 private:
   /** @private [for benchmarking access] The implementation to use */
-  std::unique_ptr<internal::dom_parser_implementation> implementation{};
+  std::unique_ptr<simdjson::internal::dom_parser_implementation> implementation{};
   size_t _capacity{0};
   size_t _max_capacity;
   size_t _max_depth{DEFAULT_MAX_DEPTH};

include/simdjson/generic/ondemand/value-inl.h

@@ -6,8 +6,6 @@
 #include "simdjson/generic/ondemand/array.h"
 #include "simdjson/generic/ondemand/array_iterator.h"
 #include "simdjson/generic/ondemand/json_iterator.h"
-#include "simdjson/generic/ondemand/json_path_to_pointer_conversion.h"
-#include "simdjson/generic/ondemand/json_path_to_pointer_conversion-inl.h"
 #include "simdjson/generic/ondemand/json_type.h"
 #include "simdjson/generic/ondemand/object.h"
 #include "simdjson/generic/ondemand/raw_json_string.h"

include/simdjson/generic/ondemand/value_iterator-inl.h

@@ -1,3 +1,4 @@
+#include <type_traits>
 #ifndef SIMDJSON_GENERIC_ONDEMAND_VALUE_ITERATOR_INL_H
 
 #ifndef SIMDJSON_CONDITIONAL_INCLUDE
@@ -6,9 +7,9 @@
 #include "simdjson/generic/atomparsing.h"
 #include "simdjson/generic/numberparsing.h"
 #include "simdjson/generic/ondemand/json_iterator.h"
+#include "simdjson/generic/ondemand/value_iterator.h"
 #include "simdjson/generic/ondemand/json_type-inl.h"
 #include "simdjson/generic/ondemand/raw_json_string-inl.h"
-#include "simdjson/generic/ondemand/value_iterator.h"
 #endif // SIMDJSON_CONDITIONAL_INCLUDE
 
 namespace simdjson {
@@ -109,6 +110,108 @@ simdjson_warn_unused simdjson_inline simdjson_result<bool> value_iterator::has_n
   }
 }
 
+template <typename Func>
+simdjson_warn_unused simdjson_inline error_code value_iterator::on_field_raw(Func&& func)
+#ifdef __cpp_lib_is_invocable
+  noexcept(std::is_nothrow_invocable_r_v<bool, Func, raw_json_string, error_code&>)
+#else
+  noexcept(false)
+#endif
+{
+#ifdef __cpp_lib_is_invocable
+  static_assert(std::is_invocable_r_v<bool, Func, raw_json_string, error_code&>, "Invalid function provided.");
+#endif
+
+  error_code error = SUCCESS;
+  bool has_value;
+  //
+  // Initially, the object can be in one of a few different places:
+  //
+  // 1. The start of the object, at the first field:
+  //
+  //    ```
+  //    { "a": [ 1, 2 ], "b": [ 3, 4 ] }
+  //      ^ (depth 2, index 1)
+  //    ```
+  if (at_first_field()) {
+    has_value = true;
+
+  //
+  // 2. When a previous search did not yield a value or the object is empty:
+  //
+  //    ```
+  //    { "a": [ 1, 2 ], "b": [ 3, 4 ] }
+  //                                     ^ (depth 0)
+  //    { }
+  //        ^ (depth 0, index 2)
+  //    ```
+  //
+  } else if (!is_open()) {
+#if SIMDJSON_DEVELOPMENT_CHECKS
+    // If we're past the end of the object, we're being iterated out of order.
+    // Note: this is not perfect detection. It's possible the user is inside some other object; if so,
+    // this object iterator will blithely scan that object for fields.
+    if (_json_iter->depth() < depth() - 1) { return OUT_OF_ORDER_ITERATION; }
+#endif
+    return EMPTY;
+
+  // 3. When a previous search found a field or an iterator yielded a value:
+  //
+  //    ```
+  //    // When a field was not fully consumed (or not even touched at all)
+  //    { "a": [ 1, 2 ], "b": [ 3, 4 ] }
+  //           ^ (depth 2)
+  //    // When a field was fully consumed
+  //    { "a": [ 1, 2 ], "b": [ 3, 4 ] }
+  //                   ^ (depth 1)
+  //    // When the last field was fully consumed
+  //    { "a": [ 1, 2 ], "b": [ 3, 4 ] }
+  //                                   ^ (depth 1)
+  //    ```
+  //
+  } else {
+    if ((error = skip_child() )) { abandon(); return error; }
+    if ((error = has_next_field().get(has_value) )) { abandon(); return error; }
+#if SIMDJSON_DEVELOPMENT_CHECKS
+    if (_json_iter->start_position(_depth) != start_position()) { return OUT_OF_ORDER_ITERATION; }
+#endif
+  }
+  while (has_value) {
+    // Get the key and colon, stopping at the value.
+    raw_json_string actual_key;
+    // size_t max_key_length = _json_iter->peek_length() - 2; // -2 for the two quotes
+    // Note: _json_iter->peek_length() - 2 might overflow if _json_iter->peek_length() < 2.
+    // field_key() advances the pointer and checks that '"' is found (corresponding to a key).
+    // The depth is left unchanged by field_key().
+    if ((error = field_key().get(actual_key) )) { abandon(); return error; };
+    // field_value() will advance and check that we find a ':' separating the
+    // key and the value. It will also increment the depth by one.
+    if ((error = field_value() )) { abandon(); return error; }
+    // If it matches, stop and return
+    // We could do it this way if we wanted to allow arbitrary
+    // key content (including escaped quotes).
+    //if (actual_key.unsafe_is_equal(max_key_length, key)) {
+    // Instead we do the following which may trigger buffer overruns if the
+    // user provides an adversarial key (containing a well placed unescaped quote
+    // character and being longer than the number of bytes remaining in the JSON
+    // input).
+    if (func(actual_key, error)) {
+      break;
+    }
+
+    // The call to skip_child is meant to skip over the value corresponding to the key.
+    // After skip_child(), we are right before the next comma (',') or the final brace ('}').
+    SIMDJSON_TRY( skip_child() ); // Skip the value entirely
+    // The has_next_field() advances the pointer and check that either ',' or '}' is found.
+    // It returns true if ',' is found, false otherwise. If anything other than ',' or '}' is found,
+    // then we are in error and we abort.
+    if ((error = has_next_field().get(has_value) )) { abandon(); return error; }
+  }
+
+  // If the loop ended, we're out of fields to look at.
+  return error;
+}
+
 simdjson_warn_unused simdjson_inline simdjson_result<bool> value_iterator::find_field_raw(const std::string_view key) noexcept {
   error_code error;
   bool has_value;
@@ -1088,4 +1191,4 @@ simdjson_inline simdjson_result<SIMDJSON_IMPLEMENTATION::ondemand::value_iterato
 
 } // namespace simdjson
 
-#endif // SIMDJSON_GENERIC_ONDEMAND_VALUE_ITERATOR_INL_H
+#endif // SIMDJSON_GENERIC_ONDEMAND_VALUE_ITERATOR_INL_H

include/simdjson/generic/ondemand/value_iterator.h

@@ -6,6 +6,12 @@
 #include "simdjson/generic/implementation_simdjson_result_base.h"
 #endif // SIMDJSON_CONDITIONAL_INCLUDE
 
+#ifdef __has_include
+#if __has_include (<version>)
+#include <version>
+#endif
+#endif
+
 namespace simdjson {
 namespace SIMDJSON_IMPLEMENTATION {
 namespace ondemand {
@@ -198,6 +204,22 @@ public:
    */
   simdjson_warn_unused simdjson_inline simdjson_result<bool> find_field_raw(const std::string_view key) noexcept;
 
+
+  /**
+   * Runs Func on each key found.
+   * Almost same as `find_field_raw` but it runs `func` instead of checking the key ourselves.
+   *
+   * @param Func func(raw_json_string key, error_code& error) noexcept
+   */
+  template <typename Func>
+  simdjson_warn_unused simdjson_inline error_code on_field_raw(Func&& func)
+#ifdef __cpp_lib_is_invocable
+  noexcept(std::is_nothrow_invocable_r_v<bool, Func, raw_json_string, error_code&>)
+#else
+  noexcept(false)
+#endif
+  ;
+
   /**
    * Find the field with the given key without regard to order, and *without* unescaping.
    *
@@ -489,4 +511,4 @@ public:
 
 } // namespace simdjson
 
-#endif // SIMDJSON_GENERIC_ONDEMAND_VALUE_ITERATOR_H
+#endif // SIMDJSON_GENERIC_ONDEMAND_VALUE_ITERATOR_H

include/simdjson/padded_string-inl.h

@@ -53,6 +53,9 @@ inline padded_string::padded_string(const char *data, size_t length) noexcept
   if ((data != nullptr) && (data_ptr != nullptr)) {
     std::memcpy(data_ptr, data, length);
   }
+  if (data_ptr == nullptr) {
+    viable_size = 0;
+  }
 }
 #ifdef __cpp_char8_t
 inline padded_string::padded_string(const char8_t *data, size_t length) noexcept
@@ -60,12 +63,17 @@ inline padded_string::padded_string(const char8_t *data, size_t length) noexcept
   if ((data != nullptr) && (data_ptr != nullptr)) {
     std::memcpy(data_ptr, reinterpret_cast<const char *>(data), length);
   }
+  if (data_ptr == nullptr) {
+    viable_size = 0;
+  }
 }
 #endif
 // note: do not pass std::string arguments by value
 inline padded_string::padded_string(const std::string & str_ ) noexcept
     : viable_size(str_.size()), data_ptr(internal::allocate_padded_buffer(str_.size())) {
-  if (data_ptr != nullptr) {
+  if (data_ptr == nullptr) {
+    viable_size = 0;
+  } else {
     std::memcpy(data_ptr, str_.data(), str_.size());
   }
 }

include/simdjson/simdjson_version.h

@@ -4,7 +4,7 @@
 #define SIMDJSON_SIMDJSON_VERSION_H
 
 /** The version of simdjson being used (major.minor.revision) */
-#define SIMDJSON_VERSION "3.10.0"
+#define SIMDJSON_VERSION "3.10.1"
 
 namespace simdjson {
 enum {
@@ -19,7 +19,7 @@ enum {
   /**
    * The revision (major.minor.REVISION) of simdjson being used.
    */
-  SIMDJSON_VERSION_REVISION = 0
+  SIMDJSON_VERSION_REVISION = 1
 };
 } // namespace simdjson
 

singleheader/simdjson.cpp

@@ -1,4 +1,4 @@
-/* auto-generated on 2024-08-01 09:31:50 -0400. Do not edit! */
+/* auto-generated on 2024-08-26 09:37:03 -0400. Do not edit! */
 /* including simdjson.cpp:  */
 /* begin file simdjson.cpp */
 #define SIMDJSON_SRC_SIMDJSON_CPP
@@ -332,6 +332,8 @@ double from_chars(const char *first, const char* end) noexcept;
 #define SIMDJSON_ISALIGNED_N(ptr, n) (((uintptr_t)(ptr) & ((n)-1)) == 0)
 
 #if SIMDJSON_REGULAR_VISUAL_STUDIO
+  // We could use [[deprecated]] but it requires C++14
+  #define simdjson_deprecated __declspec(deprecated)
 
   #define simdjson_really_inline __forceinline
   #define simdjson_never_inline __declspec(noinline)
@@ -370,6 +372,8 @@ double from_chars(const char *first, const char* end) noexcept;
   #define SIMDJSON_POP_DISABLE_UNUSED_WARNINGS
 
 #else // SIMDJSON_REGULAR_VISUAL_STUDIO
+  // We could use [[deprecated]] but it requires C++14
+  #define simdjson_deprecated __attribute__((deprecated))
 
   #define simdjson_really_inline inline __attribute__((always_inline))
   #define simdjson_never_inline inline __attribute__((noinline))

tests/ondemand/CMakeLists.txt

@@ -28,6 +28,7 @@ add_cpp_test(ondemand_to_string              LABELS ondemand acceptance per_impl
 add_cpp_test(ondemand_twitter_tests          LABELS ondemand acceptance per_implementation)
 add_cpp_test(ondemand_wrong_type_error_tests LABELS ondemand acceptance per_implementation)
 add_cpp_test(ondemand_iterate_many_csv       LABELS ondemand acceptance per_implementation)
+add_cpp_test(ondemand_extract_tests          LABELS ondemand acceptance per_implementation)
 if(NOT SIMDJSON_SANITIZE)
   add_cpp_test(ondemand_cacheline              LABELS ondemand acceptance per_implementation)
 endif()

tests/ondemand/compilation_failure_tests/CMakeLists.txt

@@ -13,7 +13,8 @@ function(add_dual_compile_test TEST_NAME)
   target_compile_definitions(${TEST_NAME}_should_not_compile PRIVATE COMPILATION_TEST_USE_FAILING_CODE=1)
 endfunction(add_dual_compile_test)
 
-
+add_dual_compile_test(iterate_object)
+add_dual_compile_test(iterate_array)
 add_dual_compile_test(iterate_char_star)
 add_dual_compile_test(iterate_string_view)
 add_dual_compile_test(iterate_temporary_buffer)

tests/ondemand/compilation_failure_tests/iterate_array.cpp

@@ -0,0 +1,34 @@
+
+#include <iostream>
+#include "simdjson.h"
+
+using namespace simdjson;
+
+int main() {
+    auto json = "[1]"_padded;
+    ondemand::parser parser;
+    auto f = [](ondemand::parser& p, simdjson::padded_string& jsons) -> ondemand::document {
+        ondemand::document doc;
+        auto error = p.iterate(jsons).get(doc);
+        if(error) { std::abort(); }
+        return doc;
+    };
+    ondemand::array arrayv;
+#if COMPILATION_TEST_USE_FAILING_CODE
+    // Not allowed as this would be unsafe, the document must remain alive.
+    auto error = f(parser).get_array().get(arrayv);
+#else
+    ondemand::document doc = f(parser, json);
+    auto error = doc.get_array().get(arrayv);
+#endif
+    if(error) {
+        std::cout << "Failure" << std::endl;
+    }
+    int64_t a = 0;
+    error = arrayv.at(0).get_int64().get(a);
+    if(error) {
+        std::cout << "failure" << std::endl;
+    }
+    printf("a = %d\n", (int)a);
+    return EXIT_SUCCESS;
+}

tests/ondemand/compilation_failure_tests/iterate_object.cpp

@@ -0,0 +1,34 @@
+
+#include <iostream>
+#include "simdjson.h"
+
+using namespace simdjson;
+
+int main() {
+    auto json = "{\"a\":1}"_padded;
+    ondemand::parser parser;
+    auto f = [](ondemand::parser& p, simdjson::padded_string& jsons) -> ondemand::document {
+        ondemand::document doc;
+        auto error = p.iterate(jsons).get(doc);
+        if(error) { std::abort(); }
+        return doc;
+    };
+    ondemand::object objv;
+#if COMPILATION_TEST_USE_FAILING_CODE
+    // Not allowed as this would be unsafe, the document must remain alive.
+    auto error = f(parser).get_object().get(objv);
+#else
+    ondemand::document doc = f(parser, json);
+    auto error = doc.get_object().get(objv);
+#endif
+    if(error) {
+        std::cout << "Failure" << std::endl;
+    }
+    int64_t a = 0;
+    error = objv["a"].get_int64().get(a);
+    if(error) {
+        std::cout << "failure" << std::endl;
+    }
+    printf("a = %d\n", (int)a);
+    return EXIT_SUCCESS;
+}

tests/ondemand/ondemand_compilation_tests.cpp

@@ -59,6 +59,22 @@ void compilation_test_3() {
     }
   }
 }
+
+// Do not run this, it is only meant to compile
+void compilation_test_4() {
+  const padded_string bogus = ""_padded;
+  ondemand::parser parser;
+  int64_t x1 = (int64_t)parser.iterate(bogus);
+  double x2 = (double)parser.iterate(bogus);
+  std::string_view x = (std::string_view)parser.iterate(bogus);
+  uint64_t x3 = (uint64_t)parser.iterate(bogus);
+  bool x4 = (bool)parser.iterate(bogus);
+  (void) x1;
+  (void) x2;
+  (void) x3;
+  (void) x4;
+  (void) x;
+}
 #endif // SIMDJSON_EXCEPTIONS
 
 int main(void) {

tests/ondemand/ondemand_extract_tests.cpp

@@ -0,0 +1,116 @@
+#include "simdjson.h"
+#include "test_ondemand.h"
+
+using namespace simdjson;
+
+namespace multi_get_tests {
+#ifdef __cpp_concepts
+struct Car {
+  std::string_view make;
+  std::string_view model;
+  std::int64_t year = 0;
+  struct wheel_size_type {
+    std::int64_t front = 0;
+    std::int64_t back = 0;
+  } wheels;
+
+  static simdjson_result<Car> create(auto& value) {
+    using ondemand::to;
+    using ondemand::sub;
+
+    simdjson::ondemand::object obj;
+    auto error = value.get_object().get(obj);
+    if (error) {
+      return error;
+    }
+    Car car{};
+    // Instead of this:
+    //     for (auto field : obj) {
+    //       simdjson::ondemand::raw_json_string key;
+    //       error = field.key().get(key);
+    //       if (error) {
+    //         return error;
+    //       }
+    //       if (key == "make") {
+    //         error = field.value().get_string(car.make);
+    //         if (error) {
+    //           return error;
+    //         }
+    //       } else if (key == "model") {
+    //         error = field.value().get_string(car.model);
+    //         if (error) {
+    //           return error;
+    //         }
+    //       } else if (key == "year") {
+    //         error = field.value().get(car.year);
+    //         if (error) {
+    //           return error;
+    //         }
+    //     }
+    //
+    // we can do this now:
+    error = obj.extract(
+      to{"wheels", sub{
+        to{"front", car.wheels.front},
+        to{"back", car.wheels.back},
+      }},
+      to{"make", car.make},
+      to{"model", car.model},
+      to{"year", [&car](auto val) {
+        car.year = val;
+      }});
+    if (error) {
+      return error;
+    }
+    return car;
+  }
+};
+
+bool car_example() {
+  TEST_START();
+  simdjson::padded_string json =
+      R"( [ { "make": "Toyota", "model": "Camry",  "year": 2018,
+       "tire_pressure": [ 40.1, 39.9 ], "wheels": { "front": 10, "back": 10 } },
+  { "make": "Kia",    "model": "Soul",   "year": 2012,
+       "tire_pressure": [ 30.1, 31.0 ], "wheels": { "front": 10, "back": 10 } },
+  { "make": "Toyota", "model": "Tercel", "year": 1999,
+       "tire_pressure": [ 29.8, 30.0 ], "wheels": { "front": 10, "back": 10 } }
+])"_padded;
+
+  simdjson::ondemand::parser parser;
+  simdjson::ondemand::document doc = parser.iterate(json);
+  for (auto val : doc) {
+    auto car = Car::create(val);
+    ASSERT_EQUAL(car.error(), SUCCESS);
+    Car const c(car.value());
+    if (c.make != "Toyota" && c.make != "Kia") {
+      return false;
+    }
+    if (c.model != "Camry" && c.model != "Soul" && c.model != "Tercel") {
+      return false;
+    }
+    if (c.year != 2018 && c.year != 2012 && c.year != 1999) {
+      return false;
+    }
+    if (c.wheels.front != 10 || c.wheels.back != 10) {
+      return false;
+    }
+  }
+
+  TEST_SUCCEED();
+}
+
+#endif
+bool run() {
+  return
+#ifdef __cpp_concepts
+      car_example() &&
+#endif
+      true;
+}
+
+} // namespace multi_get_tests
+
+int main(int argc, char *argv[]) {
+  return test_main(argc, argv, multi_get_tests::run);
+}

tests/ondemand/ondemand_json_pointer_tests.cpp

@@ -164,8 +164,7 @@ namespace json_pointer_tests {
         ASSERT_TRUE(is_scalar);
         ASSERT_ERROR(doc.at_pointer("").get(val), simdjson::SCALAR_DOCUMENT_AS_VALUE);
         std::cout << "  checking true"<< std::endl;
-        ASSERT_SUCCESS(parser.iterate(true_json).get(doc));
-        ASSERT_SUCCESS(doc.is_scalar().get(is_scalar));
+        ASSERT_SUCCESS(parser.iterate(true_json).is_scalar().get(is_scalar));
         ASSERT_TRUE(is_scalar);
         ASSERT_ERROR(doc.at_pointer("").get(val), simdjson::SCALAR_DOCUMENT_AS_VALUE);
         std::cout << "  checking object"<< std::endl;