release candidate 4.0.2 (#2441)

* release candidate 4.0.2

* more fixes

* fixing typos

* adding macro check

.github/pull_request_template.md

@@ -1,8 +1,53 @@
+Short title (summary):
+
+Description
+- What did you change and why? (1-3 sentences)
+- Issue reproduced / related issue: link the issue if relevant (e.g. #123)
+
+Type of change
+- [ ] Bug fix
+- [ ] New feature
+- [ ] Refactor / cleanup
+- [ ] Documentation / tests
+- [ ] Other (please describe):
+
+How to verify / test
+- Add additional tests to verify bugs or new features.
+- If you claim performance gains, you should provide benchmark numbers using high quality benchmarking code.
 
 
-Our tests check whether you have introduced trailing white space. If such a test fails, please check the "artifacts button" above, which if you click it gives a link to a downloadable file to help you identify the issue. You can also run scripts/remove_trailing_whitespace.sh locally if you have a bash shell and the sed command available on your system.
+Please read before contributing:
+- CONTRIBUTING: https://github.com/simdjson/simdjson/blob/master/CONTRIBUTING.md
+- HACKING: https://github.com/simdjson/simdjson/blob/master/HACKING.md
 
-If you plan to contribute to simdjson, please read our
 
-CONTRIBUTING guide: https://github.com/simdjson/simdjson/blob/master/CONTRIBUTING.md and our
-HACKING guide: https://github.com/simdjson/simdjson/blob/master/HACKING.md
+
+If you can, we recommend running our tests with the sanitizers turned on.
+For non-Visual Studio users, it is as easy as doing:
+
+
+
+```bash
+cmake -B build -D SIMDJSON_SANITIZE=ON -D SIMDJSON_DEVELOPER_MODE=ON
+cmake --build build
+ctest --test-dir build
+```
+
+
+Our CI checks, among other things, for trailing whitespace. If a test fails for that reason,
+use the "artifacts" button to download the artifact and inspect the problematic lines,
+or run `scripts/remove_trailing_whitespace.sh` locally if you have a bash shell and `sed`.
+
+
+Checklist before submitting
+- [ ] I added/updated tests covering my change (if applicable)
+- [ ] Code builds locally and passes my check
+- [ ] Documentation / README updated if needed
+- [ ] Commits are atomic and messages are clear
+- [ ] I linked the related issue (if applicable)
+
+Final notes
+- For large PRs, prefer smaller incremental PRs or request staged review.
+
+Thanks for the contribution!
+

.github/workflows/rvv-1024-clang-18.yml

@@ -0,0 +1,29 @@
+name: Ubuntu rvv VLEN=1024 (clang 18)
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+    branches:
+      - master
+
+jobs:
+  build:
+    runs-on: ubuntu-24.04
+    steps:
+    - uses: actions/checkout@v4
+    - name: Install packages
+      run: |
+        sudo apt-get update -q -y
+        sudo apt-get install -y cmake make g++-riscv64-linux-gnu qemu-user-static clang-18
+    - name: Build
+      run: |
+        CXX=clang++-18 CXXFLAGS="--target=riscv64-linux-gnu -march=rv64gcv_zvbb" \
+        cmake --toolchain=cmake/toolchains-ci/riscv64-linux-gnu.cmake -DCMAKE_BUILD_TYPE=Release -B build
+        cmake --build build/ -j$(nproc)
+    - name: Test VLEN=1024
+      run: |
+        export QEMU_LD_PREFIX="/usr/riscv64-linux-gnu"
+        export QEMU_CPU="rv64,v=on,zvbb=on,vlen=1024,rvv_ta_all_1s=on,rvv_ma_all_1s=on"
+        ctest --timeout 1800 --output-on-failure --test-dir build -j $(nproc)

.github/workflows/rvv-128-clang-17.yml

@@ -0,0 +1,29 @@
+name: Ubuntu rvv VLEN=128 (clang 17)
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+    branches:
+      - master
+
+jobs:
+  build:
+    runs-on: ubuntu-24.04
+    steps:
+    - uses: actions/checkout@v4
+    - name: Install packages
+      run: |
+        sudo apt-get update -q -y
+        sudo apt-get install -y cmake make g++-riscv64-linux-gnu qemu-user-static clang-17
+    - name: Build
+      run: |
+        CXX=clang++-17 CXXFLAGS="--target=riscv64-linux-gnu -march=rv64gcv" \
+        cmake --toolchain=cmake/toolchains-ci/riscv64-linux-gnu.cmake -DCMAKE_BUILD_TYPE=Release -B build
+        cmake --build build/ -j$(nproc)
+    - name: Test VLEN=128
+      run: |
+        export QEMU_LD_PREFIX="/usr/riscv64-linux-gnu"
+        export QEMU_CPU="rv64,v=on,vlen=128,rvv_ta_all_1s=on,rvv_ma_all_1s=on"
+        ctest --timeout 1800 --output-on-failure --test-dir build -j $(nproc)

.github/workflows/rvv-256-gcc-14.yml

@@ -0,0 +1,29 @@
+name: Ubuntu rvv VLEN=256 (gcc 14)
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+    branches:
+      - master
+
+jobs:
+  build:
+    runs-on: ubuntu-24.04
+    steps:
+    - uses: actions/checkout@v4
+    - name: Install packages
+      run: |
+        sudo apt-get update -q -y
+        sudo apt-get install -y cmake make g++-14-riscv64-linux-gnu qemu-user-static
+    - name: Build
+      run: |
+        CXX=riscv64-linux-gnu-g++-14 CXXFLAGS=-march=rv64gcv \
+        cmake --toolchain=cmake/toolchains-ci/riscv64-linux-gnu.cmake -DCMAKE_BUILD_TYPE=Release -B build
+        cmake --build build/ -j$(nproc)
+    - name: Test VLEN=256
+      run: |
+        export QEMU_LD_PREFIX="/usr/riscv64-linux-gnu"
+        export QEMU_CPU="rv64,v=on,zvbb=on,vlen=256,rvv_ta_all_1s=on,rvv_ma_all_1s=on"
+        ctest --timeout 1800 --output-on-failure --test-dir build -j $(nproc)

.github/workflows/ubuntu24-cxx20-noexcept.yml

@@ -0,0 +1,22 @@
+name: Ubuntu 24.04 CI (CXX 20, noexcept)
+
+on: [push, pull_request]
+jobs:
+  ubuntu-build:
+    if: >-
+      ! contains(toJSON(github.event.commits.*.message), '[skip ci]') &&
+      ! contains(toJSON(github.event.commits.*.message), '[skip github]')
+    runs-on: ubuntu-24.04
+    strategy:
+      matrix:
+        cxx: [g++-13, clang++-16]
+    steps:
+      - uses: actions/checkout@a5ac7e51b41094c92402da3b24376905380afc29 # v4.1.6
+      - name: Prepare
+        run: cmake -DSIMDJSON_CXX_STANDARD=20 -DSIMDJSON_EXCEPTIONS=OFF -DSIMDJSON_DEVELOPER_MODE=ON  -B build
+        env:
+          CXX: ${{matrix.cxx}}
+      - name: Build
+        run: cmake --build build -j=2
+      - name: Test
+        run: ctest --output-on-failure --test-dir build

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

@@ -0,0 +1,30 @@
+name: VS17-CI-SANITIZE
+
+on: [push, pull_request]
+
+jobs:
+  ci:
+    if: >-
+      ! contains(toJSON(github.event.commits.*.message), '[skip ci]') &&
+      ! contains(toJSON(github.event.commits.*.message), '[skip github]')
+    name: windows-vs17
+    runs-on: windows-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - {gen: Visual Studio 17 2022, arch: x64, shared: OFF, build_type: Debug}
+          - {gen: Visual Studio 17 2022, arch: x64, shared: OFF, build_type: Release}
+          - {gen: Visual Studio 17 2022, arch: x64, shared: OFF, build_type: RelWithDebInfo}
+    steps:
+    - name: checkout
+      uses: actions/checkout@v4
+    - name: Configure
+      run: |
+        cmake -G "${{matrix.gen}}" -A ${{matrix.arch}} -DSANITIZE=ON -DSIMDJSON_DEVELOPER_MODE=ON -DSIMDJSON_COMPETITION=OFF -DBUILD_SHARED_LIBS=${{matrix.shared}} -B build
+    - name: Build
+      run: cmake --build build --config ${{matrix.build_type}} --verbose
+    - name: Run tests
+      run: |
+        cd build
+        ctest -C ${{matrix.build_type}}  -LE explicitonly  --output-on-failure

.vscode/settings.json

@@ -3,6 +3,9 @@
         {"column": 95 },
         {"column": 120 }
     ],
+    "cmake.configureArgs": [
+        "-DSIMDJSON_DEVELOPER_MODE=ON"
+    ],
     "files.trimTrailingWhitespace": true,
     "files.associations": {
         ".clangd": "yaml",

CMakeLists.txt

@@ -3,7 +3,7 @@ cmake_minimum_required(VERSION 3.14)
 project(
     simdjson
     # The version number is modified by tools/release.py
-    VERSION 4.0.0
+    VERSION 4.0.2
     DESCRIPTION "Parsing gigabytes of JSON per second"
     HOMEPAGE_URL "https://simdjson.org/"
     LANGUAGES CXX C
@@ -20,8 +20,8 @@ string(
 # ---- Options, variables ----
 
 # These version numbers are modified by tools/release.py
-set(SIMDJSON_LIB_VERSION "28.0.0" CACHE STRING "simdjson library version")
-set(SIMDJSON_LIB_SOVERSION "28" CACHE STRING "simdjson library soversion")
+set(SIMDJSON_LIB_VERSION "27.0.0" CACHE STRING "simdjson library version")
+set(SIMDJSON_LIB_SOVERSION "27" CACHE STRING "simdjson library soversion")
 
 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)

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         = "4.0.0"
+PROJECT_NUMBER         = "4.0.2"
 
 # 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

HACKING.md

@@ -20,13 +20,54 @@ If you plan to contribute to simdjson, please read our [CONTRIBUTING](https://gi
 Build Quickstart
 ------------------------------
 
+For non-Windows system,
+
 ```bash
-mkdir build
-cd build
-cmake -D SIMDJSON_DEVELOPER_MODE=ON ..
-cmake --build .
+cmake -B -D SIMDJSON_DEVELOPER_MODE=ON ..
+cmake --build build
+ctest --test-dir build
 ```
 
+It is similar for Visual Studio users, please see the CMake or Visual Studio documentation.
+
+By default the library is built in Release mode.
+
+
+Assertions and development checks
+------------------------------
+
+We do not use conventional `assert` in simdjson. Instead we use the macro
+`SIMDJSON_ASSUME`:
+
+```cpp
+SIMDJSON_ASSUME(something_that_is_true());
+```
+
+Sometimes, you need to do a bit more work that a simple check.
+The `SIMDJSON_DEVELOPMENT_CHECKS` macro is true only in Debug mode unless manually set.
+It is acceptable to add checks that you would not do in Release mode as long as
+they are guarded:
+
+```cpp
+#if SIMDJSON_DEVELOPMENT_CHECKS
+// do sanity checks here
+```
+
+
+Working with sanitizers
+------------------------------
+
+The simdjson library must be memory-safe. We cannot allow buffer overruns.
+During development, if you system supports it, we recommend configuring
+the project with `-D SIMDJSON_SANITIZE=ON`.
+
+```bash
+cmake -B -D SIMDJSON_SANITIZE=ON -D SIMDJSON_DEVELOPER_MODE=ON ..
+cmake --build build
+ctest --test-dir build
+```
+
+
 Design notes
 ------------------------------
 
@@ -103,12 +144,9 @@ simdjson's source structure, from the top level, looks like this:
     * generic/stage2/*.h: `simdjson::<implementation>::stage2` namespace. Generic implementation of the tape creator, which consumes the index from stage 1 and actually parses numbers and string and such. Used for the DOM interface.
 
 Other important files and directories:
-* **.drone.yml:** Definitions for Drone CI.
-* **.appveyor.yml:** Definitions for Appveyor CI (Windows).
-* **.circleci:** Definitions for Circle CI.
 * **.github/workflows:** Definitions for GitHub Actions (CI).
 * **singleheader:** Contains generated `simdjson.h` and `simdjson.cpp` that we release. The files `singleheader/simdjson.h` and `singleheader/simdjson.cpp` should never be edited by hand.
-* **singleheader/amalgamate.py:** Generates `singleheader/simdjson.h` and `singleheader/simdjson.cpp` for release (python script).
+* **singleheader/amalgamate.py:** Generates `singleheader/simdjson.h` and `singleheader/simdjson.cpp` for release (python script). If you add a new implementation (e.g., rvv), you need to edit this file (IMPLEMENTATIONS).
 * **benchmark:** This is where we do benchmarking. Benchmarking is core to every change we make; the
   cardinal rule is don't regress performance without knowing exactly why, and what you're trading
   for it. Many of our benchmarks are microbenchmarks. We are effectively doing controlled scientific experiments for the purpose of understanding what affects our performance. So we simplify as much as possible. We try to avoid irrelevant factors such as page faults, interrupts, unnecessary system calls. We recommend checking the performance as follows:

README.md

@@ -1,5 +1,3 @@
-
-[![Fuzzing Status](https://oss-fuzz-build-logs.storage.googleapis.com/badges/simdjson.svg)](https://bugs.chromium.org/p/oss-fuzz/issues/list?sort=-opened&can=1&q=proj:simdjson)
 [![][license img]][license] [![][licensemit img]][licensemit]
 
 
@@ -121,6 +119,7 @@ Godbolt
 Some users may want to browse code along with the compiled assembly. You want to check out the following lists of examples:
 * [simdjson examples with errors handled through exceptions](https://godbolt.org/z/7G5qE4sr9)
 * [simdjson examples with errors without exceptions](https://godbolt.org/z/e9dWb9E4v)
+* [C++26 reflection example](https://godbolt.org/z/xK5TGKdPb)
 
 Performance results
 -------------------

benchmark/CMakeLists.txt

@@ -35,13 +35,16 @@ if (TARGET benchmark::benchmark)
   endif()
 endif()
 
-if(SIMDJSON_STATIC_REFLECTION)
-  add_subdirectory(static_reflect)
-endif(SIMDJSON_STATIC_REFLECTION)
-
 
 include(CheckCXXCompilerFlag)
 check_cxx_compiler_flag("-std=c++20" SIMDJSON_COMPILER_SUPPORTS_CXX20)
-if(SIMDJSON_EXCEPTIONS AND SIMDJSON_COMPILER_SUPPORTS_CXX20)
-  add_subdirectory(from)
-endif()
+if(SIMDJSON_STATIC_REFLECTION)
+  add_subdirectory(static_reflect)
+else()
+  if(SIMDJSON_EXCEPTIONS AND SIMDJSON_COMPILER_SUPPORTS_CXX20)
+    add_subdirectory(from)
+    add_subdirectory(car_builder)
+  endif()
+endif(SIMDJSON_STATIC_REFLECTION)
+
+

benchmark/car_builder/CMakeLists.txt

@@ -0,0 +1,14 @@
+# Executable
+add_executable(benchmark_car_builder benchmark_car_builder.cpp)
+
+# Compile for C++20.
+target_compile_features(benchmark_car_builder PRIVATE cxx_std_20)
+
+# Check if -march=native is supported
+include(CheckCXXCompilerFlag)
+check_cxx_compiler_flag("-march=native" SIMDJSON_SUPPORTS_MARCH_NATIVE)
+if(SIMDJSON_SUPPORTS_MARCH_NATIVE)
+  target_compile_options(benchmark_car_builder PRIVATE -march=native)
+endif()
+
+target_include_directories(benchmark_car_builder PRIVATE ${CMAKE_CURRENT_LIST_DIR}/..)

benchmark/car_builder/benchmark_car_builder.cpp

@@ -0,0 +1,127 @@
+#include "event_counter.h"
+#include <random>
+#include <vector>
+
+#include <simdjson.h>
+
+event_collector collector;
+
+struct Car {
+  std::string make;
+  std::string model;
+  int64_t year; // We deliberately do not include the tire pressure.
+};
+
+std::vector<Car> generate_random_cars(size_t count) {
+  static const std::vector<std::string> makes = {"Toyota", "Honda", "Ford",
+                                                 "BMW", "Mazda"};
+  static const std::vector<std::string> models = {"Camry", "Civic", "Focus",
+                                                  "320i", "3"};
+  static thread_local std::mt19937 rng{std::random_device{}()};
+  std::uniform_int_distribution<int> make_dist(0, makes.size() - 1);
+  std::uniform_int_distribution<int> model_dist(0, models.size() - 1);
+  std::uniform_int_distribution<int64_t> year_dist(2000, 2025);
+  std::uniform_real_distribution<double> pressure_dist(30.0, 45.0);
+
+  std::vector<Car> cars;
+  cars.reserve(count);
+  for (size_t i = 0; i < count; ++i) {
+    Car car;
+    car.make = makes[make_dist(rng)];
+    car.model = models[model_dist(rng)];
+    car.year = year_dist(rng);
+    cars.push_back(std::move(car));
+  }
+  return cars;
+}
+
+std::string_view serialize(simdjson::builder::string_builder &sb,
+                           const std::vector<Car> &cars) {
+  sb.clear();
+  sb.start_array();
+  for (const auto &car : cars) {
+    sb.start_object();
+    sb.append_key_value("make", car.make);
+    sb.append_comma();
+    sb.append_key_value("model", car.model);
+    sb.append_comma();
+    sb.append_key_value("year", car.year);
+    sb.end_object();
+  }
+  sb.end_array();
+  std::string_view result;
+  if (sb.view().get(result)) {
+    return ""; // unexpected (error)
+  }
+  return result;
+}
+
+double pretty_print(const std::string &name, size_t num_chars,
+                    std::pair<event_aggregate, size_t> result) {
+  const auto &agg = result.first;
+  size_t N = result.second;
+  num_chars *= N;
+  printf("%-40s : %8.2f ns %8.2f GB/s", name.c_str(),
+         agg.elapsed_ns() / num_chars, num_chars / agg.elapsed_ns());
+  if (collector.has_events()) {
+    printf(" %8.2f GHz %8.2f cycles/char %8.2f ins./char %8.2f i/c",
+           agg.cycles() / agg.elapsed_ns(), agg.cycles() / num_chars,
+           agg.instructions() / num_chars, agg.instructions() / agg.cycles());
+  }
+  printf("\n");
+  return num_chars / agg.elapsed_ns();
+}
+
+template <class function_type>
+std::pair<event_aggregate, size_t>
+bench(const function_type &&function, size_t min_repeat = 100,
+      size_t min_time_ns = 40'000'000, size_t max_repeat = 10000000) {
+  size_t N = min_repeat;
+  if (N == 0) {
+    N = 1;
+  }
+  event_aggregate warm_aggregate{};
+  for (size_t i = 0; i < N; i++) {
+    std::atomic_thread_fence(std::memory_order_acquire);
+    collector.start();
+    function();
+    std::atomic_thread_fence(std::memory_order_release);
+    event_count allocate_count = collector.end();
+    warm_aggregate << allocate_count;
+    if ((i + 1 == N) && (warm_aggregate.total_elapsed_ns() < min_time_ns) &&
+        (N < max_repeat)) {
+      N *= 10;
+    }
+  }
+  event_aggregate aggregate{};
+  for (size_t i = 0; i < 10; i++) {
+    std::atomic_thread_fence(std::memory_order_acquire);
+    collector.start();
+    for (size_t i = 0; i < N; i++) {
+      function();
+    }
+    std::atomic_thread_fence(std::memory_order_release);
+    event_count allocate_count = collector.end();
+    aggregate << allocate_count;
+  }
+  return {aggregate, N};
+}
+
+void run_benchmarks() {
+  std::vector<Car> source = generate_random_cars(100000);
+  simdjson::builder::string_builder sb;
+  size_t volume = serialize(sb, source).size();
+
+  pretty_print("string_builder", volume, bench([&source, &sb]() -> size_t {
+                 return serialize(sb, source).size();
+               }));
+}
+
+int main() {
+  for (size_t trial = 0; trial < 3; trial++) {
+    printf("Trial %zu:\n", trial + 1);
+    run_benchmarks();
+    printf("\n");
+  }
+  return EXIT_SUCCESS;
+}

benchmark/from/CMakeLists.txt

@@ -2,8 +2,9 @@
 add_executable(from_benchmark from_benchmark.cpp)
 
 # Compile for C++20.
-target_compile_features(from_benchmark PRIVATE cxx_std_20)
-
+if(CMAKE_CXX_STANDARD LESS 20)
+  target_compile_features(from_benchmark PRIVATE cxx_std_20)
+endif()
 # Check if -march=native is supported
 include(CheckCXXCompilerFlag)
 check_cxx_compiler_flag("-march=native" SIMDJSON_SUPPORTS_MARCH_NATIVE)

cmake/developer-options.cmake

@@ -4,7 +4,7 @@
 add_library(simdjson-internal-flags INTERFACE)
 if(NOT DEFINED CMAKE_POSITION_INDEPENDENT_CODE)
   # We default to ON for all targets, so that we can use the library in shared libraries.
-  set_target_properties(simdjson-internal-flags PROPERTIES POSITION_INDEPENDENT_CODE ON)
+  set_target_properties(simdjson-internal-flags PROPERTIES INTERFACE_POSITION_INDEPENDENT_CODE ON)
 endif(NOT DEFINED CMAKE_POSITION_INDEPENDENT_CODE)
 
 option(SIMDJSON_CHECK_EOF "Check for the end of the input buffer. The setting is unnecessary since we require padding of the inputs. You should expect tests to fail with this option turned on." OFF)
@@ -32,6 +32,9 @@ undefined behavior.")
     link_libraries(
         -fsanitize=address -fno-omit-frame-pointer -fno-sanitize-recover=all
     )
+  elseif (CMAKE_CXX_COMPILER_ID STREQUAL "MSVC")
+    add_compile_options(-fsanitize=address)
+    link_libraries(-fsanitize=address)
   else()
     message(
         STATUS

cmake/toolchains-ci/riscv64-linux-gnu.cmake

@@ -0,0 +1,4 @@
+set(CMAKE_SYSTEM_NAME Linux)
+set(CMAKE_SYSTEM_PROCESSOR riscv64)
+
+set(CMAKE_CROSSCOMPILING_EMULATOR "qemu-riscv64-static")

doc/basics.md

@@ -54,7 +54,7 @@ The simdjson library is widely deployed in popular systems such as the Node.js r
 environment.
 
 - A recent compiler (LLVM clang 6 or better, GNU GCC 7.4 or better, Xcode 11 or better) on POSIX systems such as macOS, FreeBSD or Linux. We require that the compiler supports the C++11 standard or better. We test the library on a big-endian system (IBM s390x with Linux).
-- Visual Studio 2017 or better. We support the LLVM clang compiler under Visual Studio (clang-cl) as well as as the regular Visual Studio compiler. For better release performance (both compile time and execution time), we recommend Visual Studio users adopt LLVM (clang-cl). We discourage against using GCC under Windows: there [is a long-running bug with GCC under Windows](https://gcc.gnu.org/bugzilla/show_bug.cgi?id=54412).
+- Visual Studio 2017 or better. We support the LLVM clang compiler under Visual Studio (clang-cl) as well as the regular Visual Studio compiler. For better release performance (both compile time and execution time), we recommend Visual Studio users adopt LLVM (clang-cl). We discourage using GCC under Windows: there [is a long-running bug with GCC under Windows](https://gcc.gnu.org/bugzilla/show_bug.cgi?id=54412).
 
 Support for AVX-512 require a processor with AVX512-VBMI2 support (Ice Lake or better, AMD Zen 4 or better) under a 64-bit system and a recent compiler (LLVM clang 6 or better, GCC 8 or better, Visual Studio 2019 or better). You need a correspondingly recent assembler such as gas (2.30+) or nasm (2.14+): recent compilers usually come with recent assemblers. If you mix a recent compiler with an incompatible/old assembler (e.g., when using a recent compiler with an old Linux distribution), you may get errors at build time because the compiler produces instructions that the assembler does not recognize: you should update your assembler to match your compiler (e.g., upgrade binutils to version 2.30 or better under Linux) or use an older compiler matching the capabilities of your assembler.
 
@@ -78,14 +78,14 @@ c++ myproject.cpp simdjson.cpp
 ```
 
 Note:
-- We recommend that you use simdjson by copying the single-header `simdjson.h` file along with the source file `simdjson.cpp` directly in your project, as they are part of [every release](https://github.com/simdjson/simdjson/releases) as assets. In this manner, you only have to compile `simdjson.cpp` as any other source file: it works well in every development environment. However, you may also use simdjson as a git submodule ([example](https://github.com/simdjson/cmakedemo)), using FetchContent ([example](https://github.com/simdjson/cmake_demo_single_file)), with ExternalProject_Add ([example](https://github.com/simdjson/cmakedemo_externalproject)) or with CPM ([example](https://github.com/cpm-cmake/CPM.cmake/tree/master/examples/simdjson)).
+- We recommend that you use simdjson by copying the single-header `simdjson.h` file along with the source file `simdjson.cpp` directly into your project, as they are part of [every release](https://github.com/simdjson/simdjson/releases) as assets. In this manner, you only have to compile `simdjson.cpp` as any other source file: it works well in every development environment. However, you may also use simdjson as a git submodule ([example](https://github.com/simdjson/cmakedemo)), using FetchContent ([example](https://github.com/simdjson/cmake_demo_single_file)), with ExternalProject_Add ([example](https://github.com/simdjson/cmakedemo_externalproject)) or with CPM ([example](https://github.com/cpm-cmake/CPM.cmake/tree/master/examples/simdjson)).
 - Users on macOS and other platforms where default compilers do not provide C++11 compliant by default should request it with the appropriate flag (e.g., `c++ -std=c++11 myproject.cpp simdjson.cpp`).
 - The library relies on [runtime CPU detection](implementation-selection.md): avoid specifying an architecture at compile time (e.g., `-march-native`) if you want your binaries to run everywhere.
 
 Using simdjson with package managers
 ------------------
 
-You can install the simdjson library on your system or in your project using multiple package managers such as MSYS2, the conan package manager, vcpkg, brew, the apt package manager (debian-based Linux systems), the FreeBSD package manager (FreeBSD), and so on. E.g., [we provide an complete example with vcpkg](https://github.com/simdjson/simdjson-vcpkg) that works under Windows. [Visit our wiki for more details](https://github.com/simdjson/simdjson/wiki/Installing-simdjson-with-a-package-manager).
+You can install the simdjson library on your system or in your project using multiple package managers such as MSYS2, the conan package manager, vcpkg, brew, the apt package manager (debian-based Linux systems), the FreeBSD package manager (FreeBSD), and so on. E.g., [we provide a complete example with vcpkg](https://github.com/simdjson/simdjson-vcpkg) that works under Windows. [Visit our wiki for more details](https://github.com/simdjson/simdjson/wiki/Installing-simdjson-with-a-package-manager).
 
 
 
@@ -320,7 +320,7 @@ At the cost of some memory allocation, you may convert your `std::string_view` i
 For convenience, we also allow [storing an escaped string directly into an existing string instance](#storing-directly-into-an-existing-string-instance).
 
 The `std::string_view` class has become standard as part of C++17 but it is not always available
-on compilers which only supports C++11. When we detect that `string_view` is natively
+on compilers that only supports C++11. When we detect that `string_view` is natively
 available, we define the macro `SIMDJSON_HAS_STRING_VIEW`.
 
 When we detect that it is unavailable,
@@ -343,7 +343,7 @@ We recommend that you first compile and run your code in debug mode:
 
 The simdjson code will set `SIMDJSON_DEVELOPMENT_CHECKS=1` in debug mode. Because
 the C++ standard does not provide a direct way of checking for a debug build, and
-because you may want the checks while building with otimizations, you can set
+because you may want the checks while building with optimizations, you can set
 the  macro `SIMDJSON_DEVELOPMENT_CHECKS` to 1 prior to including
 the `simdjson.h` header to enable these additional checks: just make sure you remove the
 definition once your code has been tested. When `SIMDJSON_DEVELOPMENT_CHECKS` is set to 1, the
@@ -371,9 +371,8 @@ and arrays (`simdjson::ondemand::array`).
 We also have a generic ephemeral type (`simdjson::ondemand::value`) which represents a potential
 array or object, or scalar type (`double`, `uint64_t`, `int64_t`, `bool`, `null`, string) inside
 an array or an object. Both generic types (`simdjson::ondemand::document` and
-`simdjson::ondemand::value`) have a `type()` method returning a `json_type` value describing the
-value (`json_type::array`, `json_type::object`, `json_type::number`, `json_type::string`,
-`json_type::boolean`, `json_type::null`). The `type()` method does not consume nor validate the value: e.g., you must still call `is_null()` to check that the value is a `null` even if `json_type::null` is returned. Starting with simdjson 4.0, we return `json_type::unknown` for bad tokens such as the `NaN` token in `{"key":NaN}`. A `json_type::unknown` type value indicates an error in the JSON document but you might still be able to proceed, see [General direct access to the raw JSON string](#general-direct-access-to-the-raw-json-string). A generic value (`simdjson::ondemand::value`)
+`simdjson::ondemand::value`) have a `type()` method returning a `json_type` value describing indicating the type (`json_type::array`, `json_type::object`, `json_type::number`, `json_type::string`,
+`json_type::boolean`, `json_type::null`, and `json_type::unknown` for unrecognized types). The `type()` method does not consume nor validate the value: e.g., you must still call `is_null()` to check that the value is a `null` even if `json_type::null` is returned. Starting with simdjson 4.0, we return `json_type::unknown` for bad tokens such as the `NaN` token in `{"key":NaN}`. A `json_type::unknown` type value indicates an error in the JSON document but you might still be able to proceed, see [General direct access to the raw JSON string](#general-direct-access-to-the-raw-json-string). A generic value (`simdjson::ondemand::value`)
 is only valid temporarily, as soon as you access other values, other keys in objects, etc.
 it becomes invalid: you should therefore consume the value immediately by converting it to a
 scalar type, an array or an object.
@@ -406,7 +405,7 @@ support for users who avoid exceptions. See [the simdjson error handling documen
   ondemand::object and ondemand::array. We also have explicit methods such as `get_string()`, `get_double()`,
   `get_uint64()`, `get_int64()`, `get_bool()`, `get_object()` and `get_array()`. After a cast or an explicit method,
   the number, string or boolean will be parsed, or the initial `{` or `[` will be verified for `ondemand::object` and `ondemand::array`. An exception may be thrown if
-  the cast is not possible: there error code is `simdjson::INCORRECT_TYPE` (see [Error handling](#error-handling)). Importantly, when getting an ondemand::object or ondemand::array instance, its content is
+  the cast is not possible: the error code is `simdjson::INCORRECT_TYPE` (see [Error handling](#error-handling)). Importantly, when getting an ondemand::object or ondemand::array instance, its content is
   not validated: you are only guaranteed that the corresponding initial character (`{` or `[`) is present. Thus,
   for example, you could have an ondemand::object instance pointing at the invalid JSON `{ "this is not a valid object" }`: the validation occurs as you access the content.
   The `get_string()` returns a valid UTF-8 string, after
@@ -453,7 +452,7 @@ support for users who avoid exceptions. See [the simdjson error handling documen
 * **Field Access:** To get the value of the "foo" field in an object, use `object["foo"]`. This will
   scan through the object looking for the field with the matching string, doing a character-by-character
   comparison. It may generate the error `simdjson::NO_SUCH_FIELD` if there is no such key in the object, it may throw an exception (see [Error handling](#error-handling)). For efficiency reason, you should avoid looking up the same field repeatedly: e.g., do
-  not do `object["foo"]` followed by `object["foo"]` with the same `object` instance. For best performance, you should try to query the keys in the same order they appear in the document. If you need several keys and you cannot predict the order they will appear in, it is recommended to iterate through all keys `for(auto field : object) {...}`. Generally, you should not mix and match iterating through an object (`for(auto field : object) {...}`) and key accesses (`object["foo"]`): if you need to iterate through an object after a key access, you need to call `reset()` on the object. Whenever you call `reset()`, you need to keep in mind that though you can iterate over the array repeatedly, values should be consumedonly once (e.g., repeatedly calling `unescaped_key()` on the same  key is forbidden). Keep in mind that On-Demand does not buffer or save the result of the parsing: if you repeatedly access `object["foo"]`, then it must repeatedly seek the key and parse the content. The library does not provide a distinct function to check if a key is present, instead we recommend you attempt to access the key: e.g., by doing `ondemand::value val{}; if (!object["foo"].get(val)) {...}`, you have that `val` contains the requested value inside the if clause.  It is your responsibility as a user to temporarily keep a reference to the value (`auto v = object["foo"]`), or to consume the content and store it in your own data structures. If you consume an
+  not do `object["foo"]` followed by `object["foo"]` with the same `object` instance. Generally, you should not mix and match iterating through an object (`for(auto field : object) {...}`) and key accesses (`object["foo"]`): if you need to iterate through an object after a key access, you need to call `reset()` on the object. Whenever you call `reset()`, you need to keep in mind that though you can iterate over the array repeatedly, values should be consumedonly once (e.g., repeatedly calling `unescaped_key()` on the same  key is forbidden). Keep in mind that On-Demand does not buffer or save the result of the parsing: if you repeatedly access `object["foo"]`, then it must repeatedly seek the key and parse the content. The library does not provide a distinct function to check if a key is present, instead we recommend you attempt to access the key: e.g., by doing `ondemand::value val{}; if (!object["foo"].get(val)) {...}`, you have that `val` contains the requested value inside the if clause.  It is your responsibility as a user to temporarily keep a reference to the value (`auto v = object["foo"]`), or to consume the content and store it in your own data structures. If you consume an
   object twice: `std::string_view(object["foo"]` followed by `std::string_view(object["foo"]` then your code
   is in error. Furthermore, you can only consume one field at a time, on the same object. The
   value instance you get from  `content["bids"]` becomes invalid when you call `content["asks"]`.
@@ -516,7 +515,7 @@ support for users who avoid exceptions. See [the simdjson error handling documen
   > double y = doc["y"]; // The cursor is now after the 2 (at })
   > double x = doc["x"]; // Success: [] loops back around to find "x"
   > ```
-* **Output to strings:** Given a document, a value, an array or an object in a JSON document, you can output a JSON string version suitable to be parsed again as JSON content: `simdjson::to_json_string(element)`. A call to `to_json_string` consumes fully the element: if you apply it on a document, the JSON pointer is advanced to the end of the document. The `simdjson::to_json_string` does not allocate memory. The `to_json_string` function should not be confused with retrieving the value of a string instance which are escaped and represented using a lightweight `std::string_view` instance pointing at an internal string buffer inside the parser instance. To illustrate, the first of the following two code segments will print the unescaped string `"test"` complete with the quote whereas the second one will print the escaped content of the string (without the quotes).
+* **Output to strings:** Given a document, a value, an array or an object in a JSON document, you can output a JSON string version suitable to be parsed again as JSON content: `simdjson::to_json_string(element)`. A call to `to_json_string` consumes fully the element: if you apply it on a document, the internal pointer is advanced to the end of the document. The `simdjson::to_json_string` does not allocate memory. The `to_json_string` function should not be confused with retrieving the value of a string instance which are escaped and represented using a lightweight `std::string_view` instance pointing at an internal string buffer inside the parser instance. To illustrate, the first of the following two code segments will print the unescaped string `"test"` complete with the quote whereas the second one will print the escaped content of the string (without the quotes).
   > ```C++
   > // serialize a JSON to an escaped std::string instance so that it can be parsed again as JSON
   > auto silly_json = R"( { "test": "result"  }  )"_padded;
@@ -1376,7 +1375,16 @@ your code with the `SIMDJSON_STATIC_REFLECTION` macro set:
 
 Then you can deserialize a type such as `Car` automatically:
 
-```cpp
+
+
+```C++
+struct Car {
+  std::string make;
+  std::string model;
+  int year;
+  std::vector<float> tire_pressure;
+};
+
 std::string json =  R"( { "make": "Toyota", "model": "Camry",  "year": 2018,
        "tire_pressure": [ 40.1, 39.9 ] } )";
 simdjson::ondemand::parser parser;
@@ -1385,6 +1393,75 @@ Car c = doc.get<Car>();
 ```
 
 
+We try to automate the parsing of any given structure or class
+by looking at its non-static public members. At compile-time,
+the library looks at a simple structre like `Car` and
+maps it to parsing code. We call the default constructor,
+and then assign values to the public members.
+
+
+#### Special cases
+
+However, there are instances where the construction cannot
+be easily automated. Let us consider a class without any
+public member.
+
+```cpp
+
+class MyDate {
+public:
+    void assign(std::string_view str) {
+        date_str = str;
+    }
+    const std::string& to_string() const {
+        return date_str;
+    }
+private:
+    std::string date_str;
+};
+```
+
+This class has a default constructor, but it must be initialized
+with the `assign` method. We need to help the library with
+a `tag_invoke` function (just as in the C++20 case).
+
+
+```cpp
+namespace simdjson {
+template <typename simdjson_value>
+auto tag_invoke(deserialize_tag, simdjson_value &val, MyDate& date) {
+    std::string_view str;
+    auto error = val.get_string().get(str);
+    if(error) { return error; }
+    date.assign(str);
+  return simdjson::SUCCESS;
+}
+} // namespace simdjson
+```
+
+Once this is done, we can now automatically parse a custom type
+like `complicated_weather_data` containing `MyDate` values.
+
+
+```cpp
+struct complicated_weather_data {
+    std::vector<MyDate> time;
+    std::vector<float> temperature;
+};
+```
+
+The code might as simple as the following.
+
+```cpp
+auto padded = R"({"time":["2023-03-15T12:00:00Z"],"temperature":[42]})"_padded;
+simdjson::ondemand::parser parser;
+simdjson::ondemand::document doc = parser.iterate(padded);
+complicated_weather_data p = doc.get<>(complicated_weather_data);
+```
+
+Thus you can combine C++26 static reflection with custom deserialization
+functions.
+
 You can also automatically serialize the `Car` instance to a JSON string, see
 our [Builder documentation](builder.md).
 
@@ -1460,9 +1537,9 @@ If you find yourself needing only fast Unicode functions, consider using the sim
 JSON Pointer
 ------------
 
-The simdjson library also supports [JSON pointer](https://tools.ietf.org/html/rfc6901) through the `at_pointer()` method, letting you reach further down into the document in a single call. JSON pointer is supported by both the [DOM approach](https://github.com/simdjson/simdjson/blob/master/doc/dom.md#json-pointer) as well as the On-Demand approach.
+The simdjson library also supports [JSON pointer](https://tools.ietf.org/html/rfc6901) through the `at_pointer()` method, letting you reach further down into the document in a single call. JSON Pointer is supported by both the [DOM approach](https://github.com/simdjson/simdjson/blob/master/doc/dom.md#json-pointer) as well as the On-Demand approach.
 
-**Note:** The On-Demand implementation of JSON pointer relies on `find_field` which implies that it does not unescape keys when matching.
+**Note:** The On-Demand implementation of JSON Pointer relies on `find_field` which implies that it does not unescape keys when matching.
 
 Consider the following example:
 
@@ -1482,7 +1559,7 @@ index allows you to select the indexed node. Within objects, the string value of
 select the value. If your keys contain the characters '/' or '~', they must be escaped as '~1' and
 '~0' respectively. An empty JSON Pointer Path refers to the whole document.
 
-For multiple JSON pointer queries on a document, one can call `at_pointer` multiple times.
+For multiple JSON Pointer queries on a document, one can call `at_pointer` multiple times.
 
 ```c++
 auto cars_json = R"( [
@@ -1637,7 +1714,7 @@ x = obj.at_path("$.d.foo2.a.2"); // 30
 Error handling
 --------------
 
-Error handing with exception and a single try/catch clause makes the code simple, but it gives you little control over errors. For easier debugging or more robust error handling, you may want to consider our exception-free approach.
+Error handling with exception and a single try/catch clause makes the code simple, but it gives you little control over errors. For easier debugging or more robust error handling, you may want to consider our exception-free approach.
 
 The entire simdjson API is usable with and without exceptions. All simdjson APIs that can fail return `simdjson_result<T>`, which is a &lt;value, error_code&gt;
 pair. You can retrieve the value with .get() without generating an exception, like so:
@@ -3099,10 +3176,45 @@ Performance tips
 - The On-Demand front-end works best when doing a single pass over the input: avoid calling `count_elements`, `rewind`, `reset` and similar methods.
 - If you are familiar with assembly language, you may use the online tool godbolt to explore the compiled code. The following example may work: [https://godbolt.org/z/xE4GWs573](https://godbolt.org/z/xE4GWs573).
 - Given a field `field` in an object, calling `field.key()` is often faster than `field.unescaped_key()` so if you do not need an unescaped `std::string_view` instance, prefer `field.key()`. Similarly, we expect `field.escaped_key()` to be faster than `field.unescaped_key()` even though both return a `std::string_view` instance.
-- For release builds, we recommend setting `NDEBUG` pre-processor directive when compiling the `simdjson` library. Importantly, using the optimization flags `-O2` or `-O3` under GCC and LLVM clang does not set the `NDEBUG` directive, you must set it manually (e.g., `-DNDEBUG`).
+- For release builds, we recommend setting the `NDEBUG` pre-processor directive when compiling the `simdjson` library. Importantly, using the optimization flags `-O2` or `-O3` under GCC and LLVM clang does not set the `NDEBUG` directive, you must set it manually (e.g., `-DNDEBUG`).
 - For long streams of JSON documents, consider [`iterate_many`](iterate_many.md) and [`parse_many`](parse_many.md) for better performance.
 - Never seek to access a field twice (e.g., o["data"] and later again o["data"]). Instead capture once an ondemand::value and reuse it.
-- If you must access several different keys in an object, it might be preferable to iterate through all the fields in the object instead, and branch on the field keys.
+- If you must access several different keys in an object, it might be preferable to iterate through all the fields in the object instead, and branch on the field keys. Consider this example.
+  ```cpp
+
+    auto json = R"({"price": 123.456789, "volume": 9999,
+                    "timestamp": "2025-09-04T09:45:00Z",
+                    "symbol": "XYZ", "currency": "USD", "change": 1.23,
+                    "isActive": true})"_padded;
+
+    simdjson::ondemand::parser parser;
+    simdjson::ondemand::document doc = parser.iterate(json);
+
+    for(auto keyvalue : doc.get_object()) {
+        simdjson::ondemand::raw_json_string key = keyvalue.key();
+        switch(key[0]) {
+            case 'p': // price
+                if (key == "price") {
+                    std::string_view price_str = keyvalue.value().raw_json();
+                    std::cout << "Price: " << price_str << std::endl;
+                }
+                break;
+            case 'v': // volume
+                if (key == "volume") {
+                    std::string_view volume_str = keyvalue.value().raw_json();
+                    std::cout << "Volume: " << volume_str << std::endl;
+                }
+                break;
+            case 't': // timestamp
+                if (key == "timestamp") {
+                    std::string_view timestamp = keyvalue.value();
+                    std::cout << "Timestamp: " << timestamp << std::endl;
+                }
+                break;
+            default: break;
+        }
+    }
+  ```
 - If possible, refer to each object and array in your code once. For example, the following code repeatedly refers to the `"data"` key to create an object...
 	```C++
 	std::string_view make = o["data"]["make"];

doc/builder.md

@@ -46,7 +46,7 @@ After writting the content, if you have reasons to believe that the content migh
 - `validate_unicode()`: Checks if the content in the JSON buffer is valid UTF-8. Returns: true if the content is valid UTF-8, false otherwise.
 
 You might need to do unicode validation if you have strings in your data structures containing
-malformed UTF-8.
+malformed UTF-8. Note that we do not automatically call `validate_unicode()`.
 
 Once you are satisfied, you can recover the string as follows:
 
@@ -54,7 +54,7 @@ Once you are satisfied, you can recover the string as follows:
 - `operator std::string_view()`: Converts the JSON buffer to an std::string_view.  (Might throw if an error occurred.)
 - `view()`: Returns a view of the written JSON buffer as a `simdjson_result<std::string_view>`.
 
-The later method (`view()`) is recommended.
+The later method (`view()`) is recommended.  For performance reasons, we expect you to explicitly call `validate_unicode()` as needed (e.g., prior to calling `view()`).
 
 Example: string_builder
 ---------------------------

fuzz/fuzz_minify.cpp

@@ -18,7 +18,7 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
     auto error = parser.parse(str).get(elem);
     if (error) { return 0; }
 
-    std::string minified=simdjson::minify(elem);
+    std::string minified = simdjson::minify(elem);
     (void)minified;
     return 0;
 }

include/simdjson/base.h

@@ -10,6 +10,7 @@
 #include "simdjson/error.h"
 #include "simdjson/portability.h"
 #include "simdjson/concepts.h"
+#include "simdjson/constevalutil.h"
 
 /**
  * @brief The top level simdjson namespace, containing everything the library provides.

include/simdjson/constevalutil.h

@@ -0,0 +1,53 @@
+#ifndef SIMDJSON_CONSTEVALUTIL_H
+#define SIMDJSON_CONSTEVALUTIL_H
+
+#include <string>
+#include <string_view>
+#include <array>
+
+#if SIMDJSON_CONSTEVAL
+namespace simdjson {
+namespace constevalutil {
+
+constexpr static std::array<uint8_t, 256> json_quotable_character = {
+  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+  1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0,
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
+constexpr static std::array<std::string_view, 32> control_chars = {
+    "\\u0000", "\\u0001", "\\u0002", "\\u0003", "\\u0004", "\\u0005", "\\u0006",
+    "\\u0007", "\\b", "\\t",     "\\n",     "\\u000b", "\\f",     "\\r",
+    "\\u000e", "\\u000f", "\\u0010", "\\u0011", "\\u0012", "\\u0013", "\\u0014",
+    "\\u0015", "\\u0016", "\\u0017", "\\u0018", "\\u0019", "\\u001a", "\\u001b",
+    "\\u001c", "\\u001d", "\\u001e", "\\u001f"};
+// unoptimized, meant for compile-time execution
+consteval std::string consteval_to_quoted_escaped(std::string_view input) {
+  std::string out = "\"";
+  for (char c : input) {
+    if (json_quotable_character[uint8_t(c)]) {
+      if (c == '"') {
+        out.append("\\\"");
+      } else if (c == '\\') {
+        out.append("\\\\");
+      } else {
+        std::string_view v = control_chars[uint8_t(c)];
+        out.append(v);
+      }
+    } else {
+      out.push_back(c);
+    }
+  }
+  out.push_back('"');
+  return out;
+}
+} // namespace constevalutil
+} // namespace simdjson
+#endif  // SIMDJSON_CONSTEVAL
+#endif // SIMDJSON_CONSTEVALUTIL_H

include/simdjson/error-inl.h

@@ -67,8 +67,38 @@ simdjson_inline error_code simdjson_result_base<T>::error() const noexcept {
   return this->second;
 }
 
+
+template<typename T>
+simdjson_inline bool simdjson_result_base<T>::has_value() const noexcept {
+  return this->error() == SUCCESS;
+}
+
 #if SIMDJSON_EXCEPTIONS
 
+
+template<typename T>
+simdjson_inline T& simdjson_result_base<T>::operator*() &  noexcept(false) {
+  return this->value();
+}
+
+template<typename T>
+simdjson_inline T&& simdjson_result_base<T>::operator*() &&  noexcept(false) {
+  return std::forward<internal::simdjson_result_base<T>>(*this).value();
+}
+
+template<typename T>
+simdjson_inline T* simdjson_result_base<T>::operator->() noexcept(false) {
+  if (this->error()) { throw simdjson_error(this->error()); }
+  return &this->first;
+}
+
+
+template<typename T>
+simdjson_inline const T* simdjson_result_base<T>::operator->() const noexcept(false) {
+  if (this->error()) { throw simdjson_error(this->error()); }
+  return &this->first;
+}
+
 template<typename T>
 simdjson_inline T& simdjson_result_base<T>::value() & noexcept(false) {
   if (error()) { throw simdjson_error(error()); }
@@ -93,6 +123,7 @@ simdjson_inline simdjson_result_base<T>::operator T&&() && noexcept(false) {
 
 #endif // SIMDJSON_EXCEPTIONS
 
+
 template<typename T>
 simdjson_inline const T& simdjson_result_base<T>::value_unsafe() const& noexcept {
   return this->first;

include/simdjson/error.h

@@ -108,6 +108,10 @@ namespace internal {
 /**
  * The result of a simdjson operation that could fail.
  *
+ * IMPORTANT: For the ondemand API, we use implementation_simdjson_result_base<T> as a base class
+ * to avoid some compilation issue. Thus, if you modify this class, please ensure that the ondemand
+ * implementation_simdjson_result_base<T> is also modified.
+ *
  * Gives the option of reading error codes, or throwing an exception by casting to the desired result.
  *
  * This is a base class for implementations that want to add functions to the result type for
@@ -168,8 +172,27 @@ struct simdjson_result_base : protected std::pair<T, error_code> {
    */
   simdjson_inline error_code error() const noexcept;
 
+  /**
+   * Whether there is a value.
+   */
+  simdjson_inline bool has_value() const noexcept;
 #if SIMDJSON_EXCEPTIONS
 
+  /**
+   * Dereference operator to access the contained value.
+   *
+   * @throw simdjson_error if there was an error.
+   */
+  simdjson_inline T& operator*() &  noexcept(false);
+  simdjson_inline T&& operator*() &&  noexcept(false);
+  /**
+   * Arrow operator to access members of the contained value.
+   *
+   * @throw simdjson_error if there was an error.
+   */
+  simdjson_inline T* operator->() noexcept(false);
+  simdjson_inline const T* operator->() const noexcept(false);
+
   /**
    * Get the result value.
    *
@@ -253,6 +276,7 @@ struct simdjson_result_base : protected std::pair<T, error_code> {
  */
 template<typename T>
 struct simdjson_result : public internal::simdjson_result_base<T> {
+
   /**
    * @private Create a new empty result with error = UNINITIALIZED.
    */
@@ -306,8 +330,11 @@ struct simdjson_result : public internal::simdjson_result_base<T> {
    */
   simdjson_inline error_code error() const noexcept;
 
-#if SIMDJSON_EXCEPTIONS
 
+
+#if SIMDJSON_EXCEPTIONS
+  using internal::simdjson_result_base<T>::operator*;
+  using internal::simdjson_result_base<T>::operator->;
   /**
    * Get the result value.
    *

include/simdjson/generic/implementation_simdjson_result_base-inl.h

@@ -33,8 +33,37 @@ simdjson_inline error_code implementation_simdjson_result_base<T>::error() const
   return this->second;
 }
 
+
+template<typename T>
+simdjson_inline bool implementation_simdjson_result_base<T>::has_value() const noexcept {
+  return this->error() == SUCCESS;
+}
+
 #if SIMDJSON_EXCEPTIONS
 
+template<typename T>
+simdjson_inline T& implementation_simdjson_result_base<T>::operator*() &  noexcept(false) {
+  return this->value();
+}
+
+template<typename T>
+simdjson_inline T&& implementation_simdjson_result_base<T>::operator*() &&  noexcept(false) {
+  return std::forward<implementation_simdjson_result_base<T>>(*this).value();
+}
+
+template<typename T>
+simdjson_inline T* implementation_simdjson_result_base<T>::operator->() noexcept(false) {
+  if (this->error()) { throw simdjson_error(this->error()); }
+  return &this->first;
+}
+
+
+template<typename T>
+simdjson_inline const T* implementation_simdjson_result_base<T>::operator->() const noexcept(false) {
+  if (this->error()) { throw simdjson_error(this->error()); }
+  return &this->first;
+}
+
 template<typename T>
 simdjson_inline T& implementation_simdjson_result_base<T>::value() & noexcept(false) {
   if (error()) { throw simdjson_error(error()); }

include/simdjson/generic/implementation_simdjson_result_base.h

@@ -74,6 +74,11 @@ struct implementation_simdjson_result_base {
    */
   simdjson_inline error_code error() const noexcept;
 
+  /**
+   * Whether there is a value.
+   */
+  simdjson_inline bool has_value() const noexcept;
+
 #if SIMDJSON_EXCEPTIONS
 
   /**
@@ -81,6 +86,16 @@ struct implementation_simdjson_result_base {
    *
    * @throw simdjson_error if there was an error.
    */
+  simdjson_inline T& operator*() &  noexcept(false);
+  simdjson_inline T&& operator*() &&  noexcept(false);
+  /**
+   * Arrow operator to access members of the contained value.
+   *
+   * @throw simdjson_error if there was an error.
+   */
+  simdjson_inline T* operator->() noexcept(false);
+  simdjson_inline const T* operator->() const noexcept(false);
+
   simdjson_inline T& value() & noexcept(false);
 
   /**

include/simdjson/generic/ondemand/document.h

@@ -942,6 +942,9 @@ public:
   template<typename T> simdjson_inline error_code get(T &out) & noexcept;
   template<typename T> simdjson_inline error_code get(T &out) && noexcept;
 #if SIMDJSON_EXCEPTIONS
+
+  using SIMDJSON_IMPLEMENTATION::implementation_simdjson_result_base<SIMDJSON_IMPLEMENTATION::ondemand::document>::operator*;
+  using SIMDJSON_IMPLEMENTATION::implementation_simdjson_result_base<SIMDJSON_IMPLEMENTATION::ondemand::document>::operator->;
   template <class T, typename std::enable_if<std::is_same<T, SIMDJSON_IMPLEMENTATION::ondemand::document>::value == false>::type>
   explicit simdjson_inline operator T() noexcept(false);
   simdjson_inline operator SIMDJSON_IMPLEMENTATION::ondemand::array() & noexcept(false);

include/simdjson/generic/ondemand/json_builder.h

@@ -13,7 +13,7 @@
 
 #include <charconv>
 #include <cstring>
-#include <experimental/meta>
+#include <meta>
 #include <memory>
 #include <optional>
 #include <string_view>
@@ -89,9 +89,6 @@ template<typename number_type,
 constexpr void atom(string_builder &b, const number_type t) {
   b.append(t);
 }
-#if SIMDJSON_CONSTEVAL
-consteval std::string consteval_to_quoted_escaped(std::string_view input);
-#endif
 
 template <class T>
   requires(std::is_class_v<T> && !container_but_not_string<T> &&
@@ -106,10 +103,10 @@ template <class T>
 constexpr void atom(string_builder &b, const T &t) {
   int i = 0;
   b.append('{');
-  [:expand(std::meta::nonstatic_data_members_of(^^T, std::meta::access_context::unchecked())):] >> [&]<auto dm>() {
+  template for (constexpr auto dm : std::define_static_array(std::meta::nonstatic_data_members_of(^^T, std::meta::access_context::unchecked()))) {
     if (i != 0)
       b.append(',');
-    constexpr auto key = std::define_static_string(consteval_to_quoted_escaped(std::meta::identifier_of(dm)));
+    constexpr auto key = std::define_static_string(constevalutil::consteval_to_quoted_escaped(std::meta::identifier_of(dm)));
     b.append_raw(key);
     b.append(':');
     atom(b, t.[:dm:]);
@@ -143,21 +140,16 @@ template <typename T>
   requires(std::is_enum_v<T>)
 void atom(string_builder &b, const T &e) {
 #if SIMDJSON_STATIC_REFLECTION
-  std::string_view result = "<unnamed>";
-  [:expand(std::meta::enumerators_of(^^T)):] >> [&]<auto enum_val>{
+  constexpr auto enumerators = std::define_static_array(std::meta::enumerators_of(^^T));
+  template for (constexpr auto enum_val : enumerators) {
+    constexpr auto enum_str = std::define_static_string(constevalutil::consteval_to_quoted_escaped(std::meta::identifier_of(enum_val)));
     if (e == [:enum_val:]) {
-      result = std::meta::identifier_of(enum_val);
+      b.append_raw(enum_str);
+      return;
     }
   };
-
-  if (result != "<unnamed>") {
-    b.append_raw("\"");
-    b.append_raw(result);
-    b.append_raw("\"");
-  } else {
-    // Fallback to integer if enum value not found
-    atom(b, static_cast<std::underlying_type_t<T>>(e));
-  }
+  // Fallback to integer if enum value not found
+  atom(b, static_cast<std::underlying_type_t<T>>(e));
 #else
   // Fallback: serialize as integer if reflection not available
   atom(b, static_cast<std::underlying_type_t<T>>(e));
@@ -241,10 +233,10 @@ template <class Z>
 void append(string_builder &b, const Z &z) {
   int i = 0;
   b.append('{');
-  [:expand(std::meta::nonstatic_data_members_of(^^Z, std::meta::access_context::unchecked())):] >> [&]<auto dm>() {
+  template for (constexpr auto dm : std::define_static_array(std::meta::nonstatic_data_members_of(^^Z, std::meta::access_context::unchecked()))) {
     if (i != 0)
       b.append(',');
-    constexpr auto key = std::define_static_string(consteval_to_quoted_escaped(std::meta::identifier_of(dm)));
+    constexpr auto key = std::define_static_string(constevalutil::consteval_to_quoted_escaped(std::meta::identifier_of(dm)));
     b.append_raw(key);
     b.append(':');
     atom(b, z.[:dm:]);

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

@@ -155,12 +155,17 @@ find_next_json_quotable_character(const std::string_view view,
 }
 
 SIMDJSON_CONSTEXPR_LAMBDA static std::string_view control_chars[] = {
-    "\\x0000", "\\x0001", "\\x0002", "\\x0003", "\\x0004", "\\x0005", "\\x0006",
-    "\\x0007", "\\x0008", "\\t",     "\\n",     "\\x000b", "\\f",     "\\r",
-    "\\x000e", "\\x000f", "\\x0010", "\\x0011", "\\x0012", "\\x0013", "\\x0014",
-    "\\x0015", "\\x0016", "\\x0017", "\\x0018", "\\x0019", "\\x001a", "\\x001b",
-    "\\x001c", "\\x001d", "\\x001e", "\\x001f"};
+    "\\u0000", "\\u0001", "\\u0002", "\\u0003", "\\u0004", "\\u0005", "\\u0006",
+    "\\u0007", "\\b", "\\t",     "\\n",     "\\u000b", "\\f",     "\\r",
+    "\\u000e", "\\u000f", "\\u0010", "\\u0011", "\\u0012", "\\u0013", "\\u0014",
+    "\\u0015", "\\u0016", "\\u0017", "\\u0018", "\\u0019", "\\u001a", "\\u001b",
+    "\\u001c", "\\u001d", "\\u001e", "\\u001f"};
 
+// All Unicode characters may be placed within the quotation marks, except for the
+// characters that MUST be escaped: quotation mark, reverse solidus, and the control
+// characters (U+0000 through U+001F).
+// There are two-character sequence escape representations of some popular characters:
+// \", \\, \b, \f, \n, \r, \t.
 SIMDJSON_CONSTEXPR_LAMBDA void escape_json_char(char c, char *&out) {
   if (c == '"') {
     memcpy(out, "\\\"", 2);
@@ -201,29 +206,6 @@ inline size_t write_string_escaped(const std::string_view input, char *out) {
   return out - initout;
 }
 
-#if SIMDJSON_CONSTEVAL
-// unoptimized, meant for compile-time execution
-consteval std::string consteval_to_quoted_escaped(std::string_view input) {
-  std::string out = "\"";
-  for (char c : input) {
-    if (json_quotable_character[uint8_t(c)]) {
-      if (c == '"') {
-        out.append("\\\"");
-      } else if (c == '\\') {
-        out.append("\\\\");
-      } else {
-        std::string_view v = control_chars[uint8_t(c)];
-        out.append(v);
-      }
-    } else {
-      out.push_back(c);
-    }
-  }
-  out.push_back('"');
-  return out;
-}
-#endif // SIMDJSON_CONSTEVAL
-
 simdjson_inline string_builder::string_builder(size_t initial_capacity)
     : buffer(new(std::nothrow) char[initial_capacity]), position(0),
       capacity(buffer.get() != nullptr ? initial_capacity : 0),

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

@@ -15,8 +15,13 @@ namespace ondemand {
 
 simdjson_inline raw_json_string::raw_json_string(const uint8_t * _buf) noexcept : buf{_buf} {}
 
-simdjson_inline const char * raw_json_string::raw() const noexcept { return reinterpret_cast<const char *>(buf); }
+simdjson_inline const char * raw_json_string::raw() const noexcept {
+  return reinterpret_cast<const char *>(buf);
+}
 
+simdjson_inline char raw_json_string::operator[](size_t i) const noexcept {
+  return reinterpret_cast<const char *>(buf)[i];
+}
 
 simdjson_inline bool raw_json_string::is_free_from_unescaped_quote(std::string_view target) noexcept {
   size_t pos{0};
@@ -193,6 +198,10 @@ simdjson_inline simdjson_result<const char *> simdjson_result<SIMDJSON_IMPLEMENT
   if (error()) { return error(); }
   return first.raw();
 }
+simdjson_inline char simdjson_result<SIMDJSON_IMPLEMENTATION::ondemand::raw_json_string>::operator[](size_t i) const noexcept {
+  if (error()) { return error(); }
+  return first[i];
+}
 simdjson_inline simdjson_warn_unused simdjson_result<std::string_view> simdjson_result<SIMDJSON_IMPLEMENTATION::ondemand::raw_json_string>::unescape(SIMDJSON_IMPLEMENTATION::ondemand::json_iterator &iter, bool allow_replacement) const noexcept {
   if (error()) { return error(); }
   return first.unescape(iter, allow_replacement);

include/simdjson/generic/ondemand/raw_json_string.h

@@ -58,6 +58,12 @@ public:
    */
   simdjson_inline const char * raw() const noexcept;
 
+  /**
+   * Get the character at index i. This is unchecked.
+   * [0] when the string is of length 0 returns the final quote (").
+   */
+  simdjson_inline char operator[](size_t i) const noexcept;
+
   /**
    * This compares the current instance to the std::string_view target: returns true if
    * they are byte-by-byte equal (no escaping is done) on target.size() characters,
@@ -197,10 +203,10 @@ public:
   simdjson_inline ~simdjson_result() noexcept = default; ///< @private
 
   simdjson_inline simdjson_result<const char *> raw() const noexcept;
+  simdjson_inline char operator[](size_t) const noexcept;
   simdjson_inline simdjson_warn_unused simdjson_result<std::string_view> unescape(SIMDJSON_IMPLEMENTATION::ondemand::json_iterator &iter, bool allow_replacement) const noexcept;
   simdjson_inline simdjson_warn_unused simdjson_result<std::string_view> unescape_wobbly(SIMDJSON_IMPLEMENTATION::ondemand::json_iterator &iter) const noexcept;
 };
-
 } // namespace simdjson
 
 #endif // SIMDJSON_GENERIC_ONDEMAND_RAW_JSON_STRING_H

include/simdjson/generic/ondemand/std_deserialize.h

@@ -253,7 +253,9 @@ error_code tag_invoke(deserialize_tag, auto &val, T &out) noexcept(nothrow_deser
   using value_type = typename std::remove_cvref_t<T>::value_type;
 
   // Check if the value is null
-  if (val.is_null()) {
+  bool is_null_value;
+  SIMDJSON_TRY( val.is_null().get(is_null_value) );
+  if (is_null_value) {
     out.reset(); // Set to nullopt
     return SUCCESS;
   }
@@ -275,32 +277,6 @@ constexpr bool user_defined_type = (std::is_class_v<T>
 !concepts::appendable_containers<T> && !require_custom_serialization<T>);
 
 
-// workaround from
-// https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2024/p2996r10.html#back-and-forth
-// for missing expansion statements
-namespace __impl {
-  template<auto... vals>
-  struct replicator_type {
-    template<typename F>
-      constexpr void operator>>(F body) const {
-        (body.template operator()<vals>(), ...);
-      }
-  };
-
-  template<auto... vals>
-  replicator_type<vals...> replicator = {};
-}
-
-template<typename R>
-consteval auto expand(R range) {
-  std::vector<std::meta::info> args;
-  for (auto r : range) {
-    args.push_back(reflect_constant(r));
-  }
-  return substitute(^^__impl::replicator, args);
-}
-// end of workaround
-
 template <typename T, typename ValT>
   requires(user_defined_type<T> && std::is_class_v<T>)
 error_code tag_invoke(deserialize_tag, ValT &val, T &out) noexcept {
@@ -311,9 +287,8 @@ error_code tag_invoke(deserialize_tag, ValT &val, T &out) noexcept {
     SIMDJSON_TRY(val.get_object().get(obj));
   }
   error_code e = simdjson::SUCCESS;
-
-  [:expand(std::meta::nonstatic_data_members_of(^^T, std::meta::access_context::unchecked())):] >> [&]<auto mem>() {
-    if constexpr (!std::meta::is_const(mem) && std::meta::is_public(mem)) {
+  template for (constexpr auto mem : std::define_static_array(std::meta::nonstatic_data_members_of(^^T, std::meta::access_context::unchecked()))) {
+        if constexpr (!std::meta::is_const(mem) && std::meta::is_public(mem)) {
       constexpr std::string_view key = std::define_static_string(std::meta::identifier_of(mem));
       // Note: removed static assert as optional types are now handled generically
       // as long we are succesful or the field is not found, we continue
@@ -332,16 +307,15 @@ error_code tag_invoke(deserialize_tag, ValT &val, T &out) noexcept {
 #if SIMDJSON_STATIC_REFLECTION
   std::string_view str;
   SIMDJSON_TRY(val.get_string().get(str));
-
-  bool found = false;
-  [:expand(std::meta::enumerators_of(^^T)):] >> [&]<auto enum_val>{
-    if (!found && str == std::meta::identifier_of(enum_val)) {
+  constexpr auto enumerators = std::define_static_array(std::meta::enumerators_of(^^T));
+  template for (constexpr auto enum_val : enumerators) {
+    if (str == std::meta::identifier_of(enum_val)) {
       out = [:enum_val:];
-      found = true;
+      return SUCCESS;
     }
   };
 
-  return found ? SUCCESS : INCORRECT_TYPE;
+  return INCORRECT_TYPE;
 #else
   // Fallback: deserialize as integer if reflection not available
   std::underlying_type_t<T> int_val;
@@ -389,7 +363,9 @@ error_code tag_invoke(deserialize_tag, simdjson_value &val, std::shared_ptr<T> &
 // Unique pointers
 ////////////////////////////////////////
 error_code tag_invoke(deserialize_tag, auto &val, std::unique_ptr<bool> &out) noexcept {
-  if (val.is_null()) {
+  bool is_null_value;
+  SIMDJSON_TRY( val.is_null().get(is_null_value) );
+  if (is_null_value) {
     out.reset();
     return SUCCESS;
   }
@@ -402,7 +378,9 @@ error_code tag_invoke(deserialize_tag, auto &val, std::unique_ptr<bool> &out) no
 }
 
 error_code tag_invoke(deserialize_tag, auto &val, std::unique_ptr<int64_t> &out) noexcept {
-  if (val.is_null()) {
+  bool is_null_value;
+  SIMDJSON_TRY( val.is_null().get(is_null_value) );
+  if (is_null_value) {
     out.reset();
     return SUCCESS;
   }
@@ -415,7 +393,9 @@ error_code tag_invoke(deserialize_tag, auto &val, std::unique_ptr<int64_t> &out)
 }
 
 error_code tag_invoke(deserialize_tag, auto &val, std::unique_ptr<uint64_t> &out) noexcept {
-  if (val.is_null()) {
+  bool is_null_value;
+  SIMDJSON_TRY( val.is_null().get(is_null_value) );
+  if (is_null_value) {
     out.reset();
     return SUCCESS;
   }
@@ -428,7 +408,9 @@ error_code tag_invoke(deserialize_tag, auto &val, std::unique_ptr<uint64_t> &out
 }
 
 error_code tag_invoke(deserialize_tag, auto &val, std::unique_ptr<double> &out) noexcept {
-  if (val.is_null()) {
+  bool is_null_value;
+  SIMDJSON_TRY( val.is_null().get(is_null_value) );
+  if (is_null_value) {
     out.reset();
     return SUCCESS;
   }
@@ -441,7 +423,9 @@ error_code tag_invoke(deserialize_tag, auto &val, std::unique_ptr<double> &out)
 }
 
 error_code tag_invoke(deserialize_tag, auto &val, std::unique_ptr<std::string_view> &out) noexcept {
-  if (val.is_null()) {
+  bool is_null_value;
+  SIMDJSON_TRY( val.is_null().get(is_null_value) );
+  if (is_null_value) {
     out.reset();
     return SUCCESS;
   }
@@ -458,7 +442,9 @@ error_code tag_invoke(deserialize_tag, auto &val, std::unique_ptr<std::string_vi
 // Shared pointers
 ////////////////////////////////////////
 error_code tag_invoke(deserialize_tag, auto &val, std::shared_ptr<bool> &out) noexcept {
-  if (val.is_null()) {
+  bool is_null_value;
+  SIMDJSON_TRY( val.is_null().get(is_null_value) );
+  if (is_null_value) {
     out.reset();
     return SUCCESS;
   }
@@ -471,7 +457,9 @@ error_code tag_invoke(deserialize_tag, auto &val, std::shared_ptr<bool> &out) no
 }
 
 error_code tag_invoke(deserialize_tag, auto &val, std::shared_ptr<int64_t> &out) noexcept {
-  if (val.is_null()) {
+  bool is_null_value;
+  SIMDJSON_TRY( val.is_null().get(is_null_value) );
+  if (is_null_value) {
     out.reset();
     return SUCCESS;
   }
@@ -484,7 +472,9 @@ error_code tag_invoke(deserialize_tag, auto &val, std::shared_ptr<int64_t> &out)
 }
 
 error_code tag_invoke(deserialize_tag, auto &val, std::shared_ptr<uint64_t> &out) noexcept {
-  if (val.is_null()) {
+  bool is_null_value;
+  SIMDJSON_TRY( val.is_null().get(is_null_value) );
+  if (is_null_value) {
     out.reset();
     return SUCCESS;
   }
@@ -497,7 +487,9 @@ error_code tag_invoke(deserialize_tag, auto &val, std::shared_ptr<uint64_t> &out
 }
 
 error_code tag_invoke(deserialize_tag, auto &val, std::shared_ptr<double> &out) noexcept {
-  if (val.is_null()) {
+  bool is_null_value;
+  SIMDJSON_TRY( val.is_null().get(is_null_value) );
+  if (is_null_value) {
     out.reset();
     return SUCCESS;
   }
@@ -510,7 +502,9 @@ error_code tag_invoke(deserialize_tag, auto &val, std::shared_ptr<double> &out)
 }
 
 error_code tag_invoke(deserialize_tag, auto &val, std::shared_ptr<std::string_view> &out) noexcept {
-  if (val.is_null()) {
+  bool is_null_value;
+  SIMDJSON_TRY( val.is_null().get(is_null_value) );
+  if (is_null_value) {
     out.reset();
     return SUCCESS;
   }
@@ -532,7 +526,9 @@ error_code tag_invoke(deserialize_tag, auto &val, std::shared_ptr<std::string_vi
 ////////////////////////////////////////
 error_code tag_invoke(deserialize_tag, auto &val, std::unique_ptr<std::string> &out) noexcept {
   // Check if the value is null
-  if (val.is_null()) {
+  bool is_null_value;
+  SIMDJSON_TRY( val.is_null().get(is_null_value) );
+  if (is_null_value) {
     out.reset(); // Set to nullptr
     return SUCCESS;
   }
@@ -548,7 +544,9 @@ error_code tag_invoke(deserialize_tag, auto &val, std::unique_ptr<std::string> &
 
 error_code tag_invoke(deserialize_tag, auto &val, std::shared_ptr<std::string> &out) noexcept {
   // Check if the value is null
-  if (val.is_null()) {
+  bool is_null_value;
+  SIMDJSON_TRY( val.is_null().get(is_null_value) );
+  if (is_null_value) {
     out.reset(); // Set to nullptr
     return SUCCESS;
   }
@@ -564,7 +562,9 @@ error_code tag_invoke(deserialize_tag, auto &val, std::shared_ptr<std::string> &
 
 error_code tag_invoke(deserialize_tag, auto &val, std::unique_ptr<int> &out) noexcept {
   // Check if the value is null
-  if (val.is_null()) {
+  bool is_null_value;
+  SIMDJSON_TRY( val.is_null().get(is_null_value) );
+  if (is_null_value) {
     out.reset(); // Set to nullptr
     return SUCCESS;
   }

include/simdjson/generic/ondemand/value.h

@@ -79,7 +79,9 @@ public:
       using value_type = typename std::remove_cvref_t<T>::value_type;
 
       // Check if the value is null
-      if (is_null()) {
+      bool is_null_value;
+      SIMDJSON_TRY( is_null().get(is_null_value) );
+      if (is_null_value) {
         out.reset(); // Set to nullopt
         return SUCCESS;
       }

include/simdjson/portability.h

@@ -45,6 +45,22 @@ using std::size_t;
 #define SIMDJSON_IS_ARM64 1
 #elif defined(__riscv) && __riscv_xlen == 64
 #define SIMDJSON_IS_RISCV64 1
+  #if __riscv_v_intrinsic >= 11000
+    #define SIMDJSON_HAS_RVV_INTRINSICS 1
+  #endif
+
+  #define SIMDJSON_HAS_ZVBB_INTRINSICS                                          \
+    0 // there is currently no way to detect this
+
+  #if SIMDJSON_HAS_RVV_INTRINSICS && __riscv_vector &&                          \
+      __riscv_v_min_vlen >= 128 && __riscv_v_elen >= 64
+    // RISC-V V extension
+    #define SIMDJSON_IS_RVV 1
+    #if SIMDJSON_HAS_ZVBB_INTRINSICS && __riscv_zvbb >= 1000000
+      // RISC-V Vector Basic Bit-manipulation
+      #define SIMDJSON_IS_ZVBB 1
+    #endif
+  #endif
 #elif defined(__loongarch_lp64)
 #define SIMDJSON_IS_LOONGARCH64 1
 #elif defined(__PPC64__) || defined(_M_PPC64)

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 "4.0.0"
+#define SIMDJSON_VERSION "4.0.2"
 
 namespace simdjson {
 enum {
@@ -19,7 +19,7 @@ enum {
   /**
    * The revision (major.minor.REVISION) of simdjson being used.
    */
-  SIMDJSON_VERSION_REVISION = 0
+  SIMDJSON_VERSION_REVISION = 2
 };
 } // namespace simdjson
 

p2996/README.md

@@ -78,3 +78,36 @@ You can modify the source code with your favorite editor and run again steps 5 (
 
 You can create a new docker shell at any time by running step 3 (bash script).
 
+## Using static reflection in your own projects
+
+You can import simdjson in your own CMake project. You can configure your project like so:
+
+```
+# Fetch simdjson from GitHub
+# Replace GIT_TAG by the commit you require.
+include(FetchContent)
+FetchContent_Declare(
+    simdjson
+    GIT_REPOSITORY https://github.com/simdjson/simdjson.git
+    GIT_TAG 015daad6a95a4f67c08ed5980d24b57be221c38f
+    CMAKE_ARGS -DSIMDJSON_STATIC_REFLECTION=ON
+)
+FetchContent_MakeAvailable(simdjson)
+
+##########
+# You may also use CPM.
+# https://github.com/cpm-cmake/CPM.cmake
+# CPMAddPackage(
+#    NAME simdjson
+#    GITHUB_REPOSITORY simdjson/simdjson
+#    GIT_TAG 015daad6a95a4f67c08ed5980d24b57be221c38f
+#    OPTIONS "SIMDJSON_STATIC_REFLECTION ON"
+# )
+target_link_libraries(webservice PRIVATE simdjson::simdjson)
+```
+
+Replace the `GIT_TAG` by the appropriate value.
+
+Once C++26 support will be officially available in mainstream compilers,
+we will simplify these instructions and it will no longer be needed
+to specify `SIMDJSON_STATIC_REFLECTION`.

scripts/javascript/generatelargejson.js

@@ -1,5 +1,5 @@
 
-var fs = require('fs');
+var fs = require('node:fs');
 
 var faker = require('faker');
 

singleheader/amalgamate.py

@@ -22,6 +22,9 @@ rules = """
 
 We refer your to the HACKING.md file for more information on how the project is organized.
 
+If you are trying to add a new implementation, you need to edit the amalgamate.py script
+to add your implementation to the IMPLEMENTATIONS list.
+
 To help understand the error, here are the rules for including files in simdjson:
 
 All implementation-specific files, including arm64.h, arm64/implementation.h and
@@ -480,11 +483,42 @@ AMAL_C = os.path.join(AMALGAMATE_OUTPUT_PATH, "simdjson.cpp")
 DEMOCPP = os.path.join(AMALGAMATE_OUTPUT_PATH, "amalgamate_demo.cpp")
 README = os.path.join(AMALGAMATE_OUTPUT_PATH, "README.md")
 
+def validate_implementations():
+    """Scan include/simdjson/*/implementation.h and compare with IMPLEMENTATIONS list."""
+    include_simdjson_path = os.path.join(PROJECTPATH, 'include', 'simdjson')
+    found_implementations = set()
+
+    if os.path.exists(include_simdjson_path):
+        for item in os.listdir(include_simdjson_path):
+            item_path = os.path.join(include_simdjson_path, item)
+            if os.path.isdir(item_path):
+                impl_h_path = os.path.join(item_path, 'implementation.h')
+                if os.path.exists(impl_h_path) and item != 'builtin':  # Ignore builtin
+                    found_implementations.add(item)
+
+    expected_implementations = set(IMPLEMENTATIONS)
+    if found_implementations != expected_implementations:
+        missing = expected_implementations - found_implementations
+        extra = found_implementations - expected_implementations
+        warning = "Warning: IMPLEMENTATIONS list does not match found implementations.\n"
+        if missing:
+            warning += f"Missing in filesystem: {sorted(missing)}\n"
+        if extra:
+            warning += f"Extra in filesystem: {sorted(extra)}\n"
+        print(warning)
+        return False
+    return True
+
 def read_version():
     with open(os.path.join(PROJECTPATH, 'include/simdjson/simdjson_version.h')) as f:
         return re.search(r'\d+\.\d+\.\d+', f.read()).group(0)
 
 version = read_version()
+if not validate_implementations():
+    print("Validation failed. Please update IMPLEMENTATIONS list in amalgamate.py.")
+    sys.exit(1)
+else:
+    print("implementation validated")
 Amalgamator.amalgamate(AMAL_H, "simdjson.h", ['include'], timestamp, version).validate_all_files_used('include')
 Amalgamator.amalgamate(AMAL_C, "simdjson.cpp", ['src', 'include'], timestamp, version).validate_all_files_used('src')
 

singleheader/simdjson.cpp

@@ -1,4 +1,4 @@
-/* auto-generated on 2025-08-19 20:53:13 -0400. version 4.0.0 Do not edit! */
+/* auto-generated on 2025-09-14 09:01:41 -0600. version 4.0.2 Do not edit! */
 /* including simdjson.cpp:  */
 /* begin file simdjson.cpp */
 #define SIMDJSON_SRC_SIMDJSON_CPP
@@ -193,6 +193,22 @@ using std::size_t;
 #define SIMDJSON_IS_ARM64 1
 #elif defined(__riscv) && __riscv_xlen == 64
 #define SIMDJSON_IS_RISCV64 1
+  #if __riscv_v_intrinsic >= 11000
+    #define SIMDJSON_HAS_RVV_INTRINSICS 1
+  #endif
+
+  #define SIMDJSON_HAS_ZVBB_INTRINSICS                                          \
+    0 // there is currently no way to detect this
+
+  #if SIMDJSON_HAS_RVV_INTRINSICS && __riscv_vector &&                          \
+      __riscv_v_min_vlen >= 128 && __riscv_v_elen >= 64
+    // RISC-V V extension
+    #define SIMDJSON_IS_RVV 1
+    #if SIMDJSON_HAS_ZVBB_INTRINSICS && __riscv_zvbb >= 1000000
+      // RISC-V Vector Basic Bit-manipulation
+      #define SIMDJSON_IS_ZVBB 1
+    #endif
+  #endif
 #elif defined(__loongarch_lp64)
 #define SIMDJSON_IS_LOONGARCH64 1
 #elif defined(__PPC64__) || defined(_M_PPC64)
@@ -2574,6 +2590,10 @@ namespace internal {
 /**
  * The result of a simdjson operation that could fail.
  *
+ * IMPORTANT: For the ondemand API, we use implementation_simdjson_result_base<T> as a base class
+ * to avoid some compilation issue. Thus, if you modify this class, please ensure that the ondemand
+ * implementation_simdjson_result_base<T> is also modified.
+ *
  * Gives the option of reading error codes, or throwing an exception by casting to the desired result.
  *
  * This is a base class for implementations that want to add functions to the result type for
@@ -2634,8 +2654,27 @@ struct simdjson_result_base : protected std::pair<T, error_code> {
    */
   simdjson_inline error_code error() const noexcept;
 
+  /**
+   * Whether there is a value.
+   */
+  simdjson_inline bool has_value() const noexcept;
 #if SIMDJSON_EXCEPTIONS
 
+  /**
+   * Dereference operator to access the contained value.
+   *
+   * @throw simdjson_error if there was an error.
+   */
+  simdjson_inline T& operator*() &  noexcept(false);
+  simdjson_inline T&& operator*() &&  noexcept(false);
+  /**
+   * Arrow operator to access members of the contained value.
+   *
+   * @throw simdjson_error if there was an error.
+   */
+  simdjson_inline T* operator->() noexcept(false);
+  simdjson_inline const T* operator->() const noexcept(false);
+
   /**
    * Get the result value.
    *
@@ -2719,6 +2758,7 @@ struct simdjson_result_base : protected std::pair<T, error_code> {
  */
 template<typename T>
 struct simdjson_result : public internal::simdjson_result_base<T> {
+
   /**
    * @private Create a new empty result with error = UNINITIALIZED.
    */
@@ -2772,8 +2812,11 @@ struct simdjson_result : public internal::simdjson_result_base<T> {
    */
   simdjson_inline error_code error() const noexcept;
 
-#if SIMDJSON_EXCEPTIONS
 
+
+#if SIMDJSON_EXCEPTIONS
+  using internal::simdjson_result_base<T>::operator*;
+  using internal::simdjson_result_base<T>::operator->;
   /**
    * Get the result value.
    *
@@ -2975,6 +3018,62 @@ concept optional_type = requires(std::remove_cvref_t<T> obj) {
 #endif // SIMDJSON_SUPPORTS_CONCEPTS
 #endif // SIMDJSON_CONCEPTS_H
 /* end file simdjson/concepts.h */
+/* including simdjson/constevalutil.h: #include "simdjson/constevalutil.h" */
+/* begin file simdjson/constevalutil.h */
+#ifndef SIMDJSON_CONSTEVALUTIL_H
+#define SIMDJSON_CONSTEVALUTIL_H
+
+#include <string>
+#include <string_view>
+#include <array>
+
+#if SIMDJSON_CONSTEVAL
+namespace simdjson {
+namespace constevalutil {
+
+constexpr static std::array<uint8_t, 256> json_quotable_character = {
+  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+  1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0,
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
+constexpr static std::array<std::string_view, 32> control_chars = {
+    "\\u0000", "\\u0001", "\\u0002", "\\u0003", "\\u0004", "\\u0005", "\\u0006",
+    "\\u0007", "\\b", "\\t",     "\\n",     "\\u000b", "\\f",     "\\r",
+    "\\u000e", "\\u000f", "\\u0010", "\\u0011", "\\u0012", "\\u0013", "\\u0014",
+    "\\u0015", "\\u0016", "\\u0017", "\\u0018", "\\u0019", "\\u001a", "\\u001b",
+    "\\u001c", "\\u001d", "\\u001e", "\\u001f"};
+// unoptimized, meant for compile-time execution
+consteval std::string consteval_to_quoted_escaped(std::string_view input) {
+  std::string out = "\"";
+  for (char c : input) {
+    if (json_quotable_character[uint8_t(c)]) {
+      if (c == '"') {
+        out.append("\\\"");
+      } else if (c == '\\') {
+        out.append("\\\\");
+      } else {
+        std::string_view v = control_chars[uint8_t(c)];
+        out.append(v);
+      }
+    } else {
+      out.push_back(c);
+    }
+  }
+  out.push_back('"');
+  return out;
+}
+} // namespace constevalutil
+} // namespace simdjson
+#endif  // SIMDJSON_CONSTEVAL
+#endif // SIMDJSON_CONSTEVALUTIL_H
+/* end file simdjson/constevalutil.h */
 
 /**
  * @brief The top level simdjson namespace, containing everything the library provides.
@@ -4702,8 +4801,38 @@ simdjson_inline error_code simdjson_result_base<T>::error() const noexcept {
   return this->second;
 }
 
+
+template<typename T>
+simdjson_inline bool simdjson_result_base<T>::has_value() const noexcept {
+  return this->error() == SUCCESS;
+}
+
 #if SIMDJSON_EXCEPTIONS
 
+
+template<typename T>
+simdjson_inline T& simdjson_result_base<T>::operator*() &  noexcept(false) {
+  return this->value();
+}
+
+template<typename T>
+simdjson_inline T&& simdjson_result_base<T>::operator*() &&  noexcept(false) {
+  return std::forward<internal::simdjson_result_base<T>>(*this).value();
+}
+
+template<typename T>
+simdjson_inline T* simdjson_result_base<T>::operator->() noexcept(false) {
+  if (this->error()) { throw simdjson_error(this->error()); }
+  return &this->first;
+}
+
+
+template<typename T>
+simdjson_inline const T* simdjson_result_base<T>::operator->() const noexcept(false) {
+  if (this->error()) { throw simdjson_error(this->error()); }
+  return &this->first;
+}
+
 template<typename T>
 simdjson_inline T& simdjson_result_base<T>::value() & noexcept(false) {
   if (error()) { throw simdjson_error(error()); }
@@ -4728,6 +4857,7 @@ simdjson_inline simdjson_result_base<T>::operator T&&() && noexcept(false) {
 
 #endif // SIMDJSON_EXCEPTIONS
 
+
 template<typename T>
 simdjson_inline const T& simdjson_result_base<T>::value_unsafe() const& noexcept {
   return this->first;
@@ -9158,6 +9288,11 @@ struct implementation_simdjson_result_base {
    */
   simdjson_inline error_code error() const noexcept;
 
+  /**
+   * Whether there is a value.
+   */
+  simdjson_inline bool has_value() const noexcept;
+
 #if SIMDJSON_EXCEPTIONS
 
   /**
@@ -9165,6 +9300,16 @@ struct implementation_simdjson_result_base {
    *
    * @throw simdjson_error if there was an error.
    */
+  simdjson_inline T& operator*() &  noexcept(false);
+  simdjson_inline T&& operator*() &&  noexcept(false);
+  /**
+   * Arrow operator to access members of the contained value.
+   *
+   * @throw simdjson_error if there was an error.
+   */
+  simdjson_inline T* operator->() noexcept(false);
+  simdjson_inline const T* operator->() const noexcept(false);
+
   simdjson_inline T& value() & noexcept(false);
 
   /**
@@ -10583,8 +10728,37 @@ simdjson_inline error_code implementation_simdjson_result_base<T>::error() const
   return this->second;
 }
 
+
+template<typename T>
+simdjson_inline bool implementation_simdjson_result_base<T>::has_value() const noexcept {
+  return this->error() == SUCCESS;
+}
+
 #if SIMDJSON_EXCEPTIONS
 
+template<typename T>
+simdjson_inline T& implementation_simdjson_result_base<T>::operator*() &  noexcept(false) {
+  return this->value();
+}
+
+template<typename T>
+simdjson_inline T&& implementation_simdjson_result_base<T>::operator*() &&  noexcept(false) {
+  return std::forward<implementation_simdjson_result_base<T>>(*this).value();
+}
+
+template<typename T>
+simdjson_inline T* implementation_simdjson_result_base<T>::operator->() noexcept(false) {
+  if (this->error()) { throw simdjson_error(this->error()); }
+  return &this->first;
+}
+
+
+template<typename T>
+simdjson_inline const T* implementation_simdjson_result_base<T>::operator->() const noexcept(false) {
+  if (this->error()) { throw simdjson_error(this->error()); }
+  return &this->first;
+}
+
 template<typename T>
 simdjson_inline T& implementation_simdjson_result_base<T>::value() & noexcept(false) {
   if (error()) { throw simdjson_error(error()); }
@@ -15598,6 +15772,11 @@ struct implementation_simdjson_result_base {
    */
   simdjson_inline error_code error() const noexcept;
 
+  /**
+   * Whether there is a value.
+   */
+  simdjson_inline bool has_value() const noexcept;
+
 #if SIMDJSON_EXCEPTIONS
 
   /**
@@ -15605,6 +15784,16 @@ struct implementation_simdjson_result_base {
    *
    * @throw simdjson_error if there was an error.
    */
+  simdjson_inline T& operator*() &  noexcept(false);
+  simdjson_inline T&& operator*() &&  noexcept(false);
+  /**
+   * Arrow operator to access members of the contained value.
+   *
+   * @throw simdjson_error if there was an error.
+   */
+  simdjson_inline T* operator->() noexcept(false);
+  simdjson_inline const T* operator->() const noexcept(false);
+
   simdjson_inline T& value() & noexcept(false);
 
   /**
@@ -17023,8 +17212,37 @@ simdjson_inline error_code implementation_simdjson_result_base<T>::error() const
   return this->second;
 }
 
+
+template<typename T>
+simdjson_inline bool implementation_simdjson_result_base<T>::has_value() const noexcept {
+  return this->error() == SUCCESS;
+}
+
 #if SIMDJSON_EXCEPTIONS
 
+template<typename T>
+simdjson_inline T& implementation_simdjson_result_base<T>::operator*() &  noexcept(false) {
+  return this->value();
+}
+
+template<typename T>
+simdjson_inline T&& implementation_simdjson_result_base<T>::operator*() &&  noexcept(false) {
+  return std::forward<implementation_simdjson_result_base<T>>(*this).value();
+}
+
+template<typename T>
+simdjson_inline T* implementation_simdjson_result_base<T>::operator->() noexcept(false) {
+  if (this->error()) { throw simdjson_error(this->error()); }
+  return &this->first;
+}
+
+
+template<typename T>
+simdjson_inline const T* implementation_simdjson_result_base<T>::operator->() const noexcept(false) {
+  if (this->error()) { throw simdjson_error(this->error()); }
+  return &this->first;
+}
+
 template<typename T>
 simdjson_inline T& implementation_simdjson_result_base<T>::value() & noexcept(false) {
   if (error()) { throw simdjson_error(error()); }
@@ -21893,6 +22111,11 @@ struct implementation_simdjson_result_base {
    */
   simdjson_inline error_code error() const noexcept;
 
+  /**
+   * Whether there is a value.
+   */
+  simdjson_inline bool has_value() const noexcept;
+
 #if SIMDJSON_EXCEPTIONS
 
   /**
@@ -21900,6 +22123,16 @@ struct implementation_simdjson_result_base {
    *
    * @throw simdjson_error if there was an error.
    */
+  simdjson_inline T& operator*() &  noexcept(false);
+  simdjson_inline T&& operator*() &&  noexcept(false);
+  /**
+   * Arrow operator to access members of the contained value.
+   *
+   * @throw simdjson_error if there was an error.
+   */
+  simdjson_inline T* operator->() noexcept(false);
+  simdjson_inline const T* operator->() const noexcept(false);
+
   simdjson_inline T& value() & noexcept(false);
 
   /**
@@ -23318,8 +23551,37 @@ simdjson_inline error_code implementation_simdjson_result_base<T>::error() const
   return this->second;
 }
 
+
+template<typename T>
+simdjson_inline bool implementation_simdjson_result_base<T>::has_value() const noexcept {
+  return this->error() == SUCCESS;
+}
+
 #if SIMDJSON_EXCEPTIONS
 
+template<typename T>
+simdjson_inline T& implementation_simdjson_result_base<T>::operator*() &  noexcept(false) {
+  return this->value();
+}
+
+template<typename T>
+simdjson_inline T&& implementation_simdjson_result_base<T>::operator*() &&  noexcept(false) {
+  return std::forward<implementation_simdjson_result_base<T>>(*this).value();
+}
+
+template<typename T>
+simdjson_inline T* implementation_simdjson_result_base<T>::operator->() noexcept(false) {
+  if (this->error()) { throw simdjson_error(this->error()); }
+  return &this->first;
+}
+
+
+template<typename T>
+simdjson_inline const T* implementation_simdjson_result_base<T>::operator->() const noexcept(false) {
+  if (this->error()) { throw simdjson_error(this->error()); }
+  return &this->first;
+}
+
 template<typename T>
 simdjson_inline T& implementation_simdjson_result_base<T>::value() & noexcept(false) {
   if (error()) { throw simdjson_error(error()); }
@@ -28345,6 +28607,11 @@ struct implementation_simdjson_result_base {
    */
   simdjson_inline error_code error() const noexcept;
 
+  /**
+   * Whether there is a value.
+   */
+  simdjson_inline bool has_value() const noexcept;
+
 #if SIMDJSON_EXCEPTIONS
 
   /**
@@ -28352,6 +28619,16 @@ struct implementation_simdjson_result_base {
    *
    * @throw simdjson_error if there was an error.
    */
+  simdjson_inline T& operator*() &  noexcept(false);
+  simdjson_inline T&& operator*() &&  noexcept(false);
+  /**
+   * Arrow operator to access members of the contained value.
+   *
+   * @throw simdjson_error if there was an error.
+   */
+  simdjson_inline T* operator->() noexcept(false);
+  simdjson_inline const T* operator->() const noexcept(false);
+
   simdjson_inline T& value() & noexcept(false);
 
   /**
@@ -29770,8 +30047,37 @@ simdjson_inline error_code implementation_simdjson_result_base<T>::error() const
   return this->second;
 }
 
+
+template<typename T>
+simdjson_inline bool implementation_simdjson_result_base<T>::has_value() const noexcept {
+  return this->error() == SUCCESS;
+}
+
 #if SIMDJSON_EXCEPTIONS
 
+template<typename T>
+simdjson_inline T& implementation_simdjson_result_base<T>::operator*() &  noexcept(false) {
+  return this->value();
+}
+
+template<typename T>
+simdjson_inline T&& implementation_simdjson_result_base<T>::operator*() &&  noexcept(false) {
+  return std::forward<implementation_simdjson_result_base<T>>(*this).value();
+}
+
+template<typename T>
+simdjson_inline T* implementation_simdjson_result_base<T>::operator->() noexcept(false) {
+  if (this->error()) { throw simdjson_error(this->error()); }
+  return &this->first;
+}
+
+
+template<typename T>
+simdjson_inline const T* implementation_simdjson_result_base<T>::operator->() const noexcept(false) {
+  if (this->error()) { throw simdjson_error(this->error()); }
+  return &this->first;
+}
+
 template<typename T>
 simdjson_inline T& implementation_simdjson_result_base<T>::value() & noexcept(false) {
   if (error()) { throw simdjson_error(error()); }
@@ -35156,6 +35462,11 @@ struct implementation_simdjson_result_base {
    */
   simdjson_inline error_code error() const noexcept;
 
+  /**
+   * Whether there is a value.
+   */
+  simdjson_inline bool has_value() const noexcept;
+
 #if SIMDJSON_EXCEPTIONS
 
   /**
@@ -35163,6 +35474,16 @@ struct implementation_simdjson_result_base {
    *
    * @throw simdjson_error if there was an error.
    */
+  simdjson_inline T& operator*() &  noexcept(false);
+  simdjson_inline T&& operator*() &&  noexcept(false);
+  /**
+   * Arrow operator to access members of the contained value.
+   *
+   * @throw simdjson_error if there was an error.
+   */
+  simdjson_inline T* operator->() noexcept(false);
+  simdjson_inline const T* operator->() const noexcept(false);
+
   simdjson_inline T& value() & noexcept(false);
 
   /**
@@ -36581,8 +36902,37 @@ simdjson_inline error_code implementation_simdjson_result_base<T>::error() const
   return this->second;
 }
 
+
+template<typename T>
+simdjson_inline bool implementation_simdjson_result_base<T>::has_value() const noexcept {
+  return this->error() == SUCCESS;
+}
+
 #if SIMDJSON_EXCEPTIONS
 
+template<typename T>
+simdjson_inline T& implementation_simdjson_result_base<T>::operator*() &  noexcept(false) {
+  return this->value();
+}
+
+template<typename T>
+simdjson_inline T&& implementation_simdjson_result_base<T>::operator*() &&  noexcept(false) {
+  return std::forward<implementation_simdjson_result_base<T>>(*this).value();
+}
+
+template<typename T>
+simdjson_inline T* implementation_simdjson_result_base<T>::operator->() noexcept(false) {
+  if (this->error()) { throw simdjson_error(this->error()); }
+  return &this->first;
+}
+
+
+template<typename T>
+simdjson_inline const T* implementation_simdjson_result_base<T>::operator->() const noexcept(false) {
+  if (this->error()) { throw simdjson_error(this->error()); }
+  return &this->first;
+}
+
 template<typename T>
 simdjson_inline T& implementation_simdjson_result_base<T>::value() & noexcept(false) {
   if (error()) { throw simdjson_error(error()); }
@@ -41789,6 +42139,11 @@ struct implementation_simdjson_result_base {
    */
   simdjson_inline error_code error() const noexcept;
 
+  /**
+   * Whether there is a value.
+   */
+  simdjson_inline bool has_value() const noexcept;
+
 #if SIMDJSON_EXCEPTIONS
 
   /**
@@ -41796,6 +42151,16 @@ struct implementation_simdjson_result_base {
    *
    * @throw simdjson_error if there was an error.
    */
+  simdjson_inline T& operator*() &  noexcept(false);
+  simdjson_inline T&& operator*() &&  noexcept(false);
+  /**
+   * Arrow operator to access members of the contained value.
+   *
+   * @throw simdjson_error if there was an error.
+   */
+  simdjson_inline T* operator->() noexcept(false);
+  simdjson_inline const T* operator->() const noexcept(false);
+
   simdjson_inline T& value() & noexcept(false);
 
   /**
@@ -43214,8 +43579,37 @@ simdjson_inline error_code implementation_simdjson_result_base<T>::error() const
   return this->second;
 }
 
+
+template<typename T>
+simdjson_inline bool implementation_simdjson_result_base<T>::has_value() const noexcept {
+  return this->error() == SUCCESS;
+}
+
 #if SIMDJSON_EXCEPTIONS
 
+template<typename T>
+simdjson_inline T& implementation_simdjson_result_base<T>::operator*() &  noexcept(false) {
+  return this->value();
+}
+
+template<typename T>
+simdjson_inline T&& implementation_simdjson_result_base<T>::operator*() &&  noexcept(false) {
+  return std::forward<implementation_simdjson_result_base<T>>(*this).value();
+}
+
+template<typename T>
+simdjson_inline T* implementation_simdjson_result_base<T>::operator->() noexcept(false) {
+  if (this->error()) { throw simdjson_error(this->error()); }
+  return &this->first;
+}
+
+
+template<typename T>
+simdjson_inline const T* implementation_simdjson_result_base<T>::operator->() const noexcept(false) {
+  if (this->error()) { throw simdjson_error(this->error()); }
+  return &this->first;
+}
+
 template<typename T>
 simdjson_inline T& implementation_simdjson_result_base<T>::value() & noexcept(false) {
   if (error()) { throw simdjson_error(error()); }
@@ -47868,6 +48262,11 @@ struct implementation_simdjson_result_base {
    */
   simdjson_inline error_code error() const noexcept;
 
+  /**
+   * Whether there is a value.
+   */
+  simdjson_inline bool has_value() const noexcept;
+
 #if SIMDJSON_EXCEPTIONS
 
   /**
@@ -47875,6 +48274,16 @@ struct implementation_simdjson_result_base {
    *
    * @throw simdjson_error if there was an error.
    */
+  simdjson_inline T& operator*() &  noexcept(false);
+  simdjson_inline T&& operator*() &&  noexcept(false);
+  /**
+   * Arrow operator to access members of the contained value.
+   *
+   * @throw simdjson_error if there was an error.
+   */
+  simdjson_inline T* operator->() noexcept(false);
+  simdjson_inline const T* operator->() const noexcept(false);
+
   simdjson_inline T& value() & noexcept(false);
 
   /**
@@ -49293,8 +49702,37 @@ simdjson_inline error_code implementation_simdjson_result_base<T>::error() const
   return this->second;
 }
 
+
+template<typename T>
+simdjson_inline bool implementation_simdjson_result_base<T>::has_value() const noexcept {
+  return this->error() == SUCCESS;
+}
+
 #if SIMDJSON_EXCEPTIONS
 
+template<typename T>
+simdjson_inline T& implementation_simdjson_result_base<T>::operator*() &  noexcept(false) {
+  return this->value();
+}
+
+template<typename T>
+simdjson_inline T&& implementation_simdjson_result_base<T>::operator*() &&  noexcept(false) {
+  return std::forward<implementation_simdjson_result_base<T>>(*this).value();
+}
+
+template<typename T>
+simdjson_inline T* implementation_simdjson_result_base<T>::operator->() noexcept(false) {
+  if (this->error()) { throw simdjson_error(this->error()); }
+  return &this->first;
+}
+
+
+template<typename T>
+simdjson_inline const T* implementation_simdjson_result_base<T>::operator->() const noexcept(false) {
+  if (this->error()) { throw simdjson_error(this->error()); }
+  return &this->first;
+}
+
 template<typename T>
 simdjson_inline T& implementation_simdjson_result_base<T>::value() & noexcept(false) {
   if (error()) { throw simdjson_error(error()); }
@@ -53539,6 +53977,11 @@ struct implementation_simdjson_result_base {
    */
   simdjson_inline error_code error() const noexcept;
 
+  /**
+   * Whether there is a value.
+   */
+  simdjson_inline bool has_value() const noexcept;
+
 #if SIMDJSON_EXCEPTIONS
 
   /**
@@ -53546,6 +53989,16 @@ struct implementation_simdjson_result_base {
    *
    * @throw simdjson_error if there was an error.
    */
+  simdjson_inline T& operator*() &  noexcept(false);
+  simdjson_inline T&& operator*() &&  noexcept(false);
+  /**
+   * Arrow operator to access members of the contained value.
+   *
+   * @throw simdjson_error if there was an error.
+   */
+  simdjson_inline T* operator->() noexcept(false);
+  simdjson_inline const T* operator->() const noexcept(false);
+
   simdjson_inline T& value() & noexcept(false);
 
   /**
@@ -54964,8 +55417,37 @@ simdjson_inline error_code implementation_simdjson_result_base<T>::error() const
   return this->second;
 }
 
+
+template<typename T>
+simdjson_inline bool implementation_simdjson_result_base<T>::has_value() const noexcept {
+  return this->error() == SUCCESS;
+}
+
 #if SIMDJSON_EXCEPTIONS
 
+template<typename T>
+simdjson_inline T& implementation_simdjson_result_base<T>::operator*() &  noexcept(false) {
+  return this->value();
+}
+
+template<typename T>
+simdjson_inline T&& implementation_simdjson_result_base<T>::operator*() &&  noexcept(false) {
+  return std::forward<implementation_simdjson_result_base<T>>(*this).value();
+}
+
+template<typename T>
+simdjson_inline T* implementation_simdjson_result_base<T>::operator->() noexcept(false) {
+  if (this->error()) { throw simdjson_error(this->error()); }
+  return &this->first;
+}
+
+
+template<typename T>
+simdjson_inline const T* implementation_simdjson_result_base<T>::operator->() const noexcept(false) {
+  if (this->error()) { throw simdjson_error(this->error()); }
+  return &this->first;
+}
+
 template<typename T>
 simdjson_inline T& implementation_simdjson_result_base<T>::value() & noexcept(false) {
   if (error()) { throw simdjson_error(error()); }

tests/builder/builder_string_builder_tests.cpp

@@ -16,6 +16,66 @@ struct Car {
 namespace builder_tests {
   using namespace std;
 
+    bool allchar_test() {
+        TEST_START();
+        auto get_utf8_codepoints = []() -> std::string {
+            std::string result;
+            for (char32_t cp = 0; cp <= 0x10FFFF; ++cp) {
+                if ((cp >= 0xD800 && cp <= 0xDFFF) || cp > 0x10FFFF) {
+                    continue; // Skip surrogate pairs and invalid codepoints
+                }
+                if (cp < 0x80) {
+                    result += static_cast<char>(cp);
+                } else if (cp < 0x800) {
+                    result += static_cast<char>(0xC0 | (cp >> 6));
+                    result += static_cast<char>(0x80 | (cp & 0x3F));
+                } else if (cp < 0x10000) {
+                    result += static_cast<char>(0xE0 | (cp >> 12));
+                    result += static_cast<char>(0x80 | ((cp >> 6) & 0x3F));
+                    result += static_cast<char>(0x80 | (cp & 0x3F));
+                } else {
+                    result += static_cast<char>(0xF0 | (cp >> 18));
+                    result += static_cast<char>(0x80 | ((cp >> 12) & 0x3F));
+                    result += static_cast<char>(0x80 | ((cp >> 6) & 0x3F));
+                    result += static_cast<char>(0x80 | (cp & 0x3F));
+                }
+            }
+            return result;
+        };
+        auto allutf8 = get_utf8_codepoints();
+        simdjson::builder::string_builder sb;
+        sb.start_object();
+        sb.append_key_value("input", allutf8);
+        sb.end_object();
+        std::string_view p;
+        ASSERT_TRUE(sb.validate_unicode());
+        auto result = sb.view().get(p);
+        ASSERT_SUCCESS(result);
+        simdjson::padded_string output = p;
+        simdjson::ondemand::parser parser;
+        simdjson::ondemand::document doc;
+        ASSERT_SUCCESS(parser.iterate(output).get(doc));
+        std::string_view recovered;
+        ASSERT_SUCCESS(doc["input"].get(recovered));
+        ASSERT_EQUAL(recovered, allutf8);
+        simdjson::dom::parser domparser;
+        simdjson::dom::element elem;
+        ASSERT_SUCCESS(domparser.parse(output).get(elem));
+        ASSERT_SUCCESS(elem["input"].get(recovered));
+        ASSERT_EQUAL(recovered, allutf8);
+        TEST_SUCCEED();
+    }
+
+    bool bad_utf8_test() {
+        TEST_START();
+        std::string bad_utf8 = "\xFF";
+        simdjson::builder::string_builder sb;
+        sb.start_object();
+        sb.append_key_value("input", bad_utf8);
+        sb.end_object();
+        ASSERT_FALSE(sb.validate_unicode())
+        TEST_SUCCEED();
+    }
     #if SIMDJSON_EXCEPTIONS
     bool string_convertion_except() {
         TEST_START();
@@ -449,6 +509,8 @@ namespace builder_tests {
     #endif
     bool run() {
         return
+            allchar_test() &&
+            bad_utf8_test() &&
             various_integers() &&
             various_unsigned_integers() &&
             car_test_long() &&

tests/builder/static_reflection_enum_tests.cpp

@@ -131,6 +131,7 @@ namespace builder_tests {
 
     // Deserialize
     ondemand::parser parser;
+    std::cout << json << std::endl;
     auto doc_result = parser.iterate(pad(json));
     ASSERT_SUCCESS(doc_result);
 

tests/dom/basictests.cpp

@@ -1795,6 +1795,18 @@ namespace validate_tests {
     return true;
   }
 
+  bool shall_not_parse() {
+    std::cout << "Running " << __func__ << std::endl;
+    auto test = "{\"joe\":\"\xf0\x8f\xbf\xbf\"}"_padded;
+    simdjson::dom::parser parser;
+    simdjson::dom::element doc;
+    auto error = parser.parse(test).get(doc);
+    if(error) {
+      return true; // expected
+    }
+    return false;
+  }
+
   bool test_validate() {
     std::cout << "Running " << __func__ << std::endl;
     const std::string test = R"({ "foo" : 1, "bar" : [ 1, 2, 3 ], "baz": { "a": 1, "b": 2, "c": 3 } })";
@@ -1860,6 +1872,7 @@ namespace validate_tests {
   }
   bool run() {
     return issue1187() &&
+           shall_not_parse() &&
            test_range() &&
            test_issue1169_long() &&
            test_issue1169() &&

tests/dom/ranges_test.cpp

@@ -8,7 +8,7 @@
 
 using namespace simdjson;
 namespace ranges_test {
-
+#if SIMDJSON_EXCEPTIONS
   bool printout() {
     TEST_START();
     auto cars_json = R"( [
@@ -43,6 +43,7 @@ namespace ranges_test {
     ASSERT_TRUE(std::ranges::equal(cars, expected));
     TEST_SUCCEED();
   }
+  #endif // SIMDJSON_EXCEPTIONS
 
   bool run() {
     return

tests/ondemand/ondemand_convert_tests.cpp

@@ -7,6 +7,39 @@
 #include <string>
 #include <vector>
 
+#if SIMDJSON_STATIC_REFLECTION
+
+class MyDate {
+public:
+    void assign(std::string_view str) {
+        date_str = str;
+    }
+    const std::string& to_string() const {
+        return date_str;
+    }
+private:
+    std::string date_str;
+};
+
+namespace simdjson {
+template <typename simdjson_value>
+auto tag_invoke(deserialize_tag, simdjson_value &val, MyDate& date) {
+    std::string_view str;
+    auto error = val.get_string().get(str);
+    if(error) { return error; }
+    date.assign(str);
+  return simdjson::SUCCESS;
+}
+} // namespace simdjson
+
+struct complicated_weather_data {
+    std::vector<MyDate> time;
+    std::vector<float> temperature;
+};
+
+
+#endif
+
 #ifdef __cpp_lib_ranges
 
 namespace convert_tests {
@@ -87,6 +120,47 @@ bool simple() {
   TEST_SUCCEED();
 }
 
+
+  struct BadPlayer {
+      int username;  // Oops, should be string!
+      int level;
+      double health;
+  };
+#if SIMDJSON_STATIC_REFLECTION
+  bool bad_player() {
+    TEST_START();
+    // username is a string but we declared it as an int
+    std::string json = R"({"username":"Alice","level":42,"health":100.0})";
+    simdjson::padded_string padded(json);
+    BadPlayer p;
+    simdjson::ondemand::parser parser;
+    auto doc = parser.iterate(padded);
+    ASSERT_FAILURE(doc.get(p));
+    TEST_SUCCEED();
+  }
+  bool good_player() {
+    TEST_START();
+    std::string json = R"({"username":123,"level":42,"health":100.0})";
+    simdjson::padded_string padded(json);
+    BadPlayer p;
+    simdjson::ondemand::parser parser;
+    simdjson::ondemand::document doc;
+    ASSERT_SUCCESS(parser.iterate(padded).get(doc));
+    ASSERT_SUCCESS(doc.get(p));
+    TEST_SUCCEED();
+  }
+  bool complicated_weather_test() {
+    TEST_START();
+    std::string json = R"({"time":["2023-03-15T12:00:00Z"],"temperature":[42]})";
+    simdjson::padded_string padded(json);
+    complicated_weather_data p;
+    simdjson::ondemand::parser parser;
+    simdjson::ondemand::document doc;
+    ASSERT_SUCCESS(parser.iterate(padded).get(doc));
+    ASSERT_SUCCESS(doc.get(p));
+    TEST_SUCCEED();
+  }
+#endif
 bool broken() {
   TEST_START();
   simdjson::padded_string short_json_cars = R"( { "make )"_padded;
@@ -340,6 +414,9 @@ bool test_to_vs_from_equivalence() {
 #endif // SIMDJSON_EXCEPTIONS
 bool run() {
   return
+#if SIMDJSON_STATIC_REFLECTION
+      bad_player() && good_player() && complicated_weather_test() &&
+#endif
 #if SIMDJSON_EXCEPTIONS && SIMDJSON_SUPPORTS_CONCEPTS
       broken() && simple() && simple_optional() && with_parser() && to_array() &&
       to_bad_array() &&

tests/ondemand/ondemand_error_tests.cpp

@@ -397,6 +397,25 @@ namespace error_tests {
   }
 #endif // SIMDJSON_EXCEPTIONS
 
+#if SIMDJSON_EXCEPTIONS
+  bool operator_tests() {
+    TEST_START();
+    ondemand::parser parser;
+
+    // Test successful case
+    auto json = R"({ "key": "value", "number": 42 })"_padded;
+    parser.iterate(json).value(); // Test operator*
+    *parser.iterate(json); // Test operator*
+    auto doc_result = parser.iterate(json);
+    ASSERT_SUCCESS(doc_result.error());
+
+    ASSERT_TRUE(doc_result.has_value());
+    double x = doc_result->find_field("number").get<double>();
+    ASSERT_EQUAL(x, 42.0);
+    TEST_SUCCEED();
+  }
+#endif // SIMDJSON_EXCEPTIONS
+
   bool run() {
     return
            issue2120() &&
@@ -419,6 +438,7 @@ namespace error_tests {
 #if SIMDJSON_EXCEPTIONS
            invalid_type() &&
            simple_error_example_except() &&
+           operator_tests() &&
 #endif
            true;
   }

tests/ondemand/ondemand_readme_examples.cpp

@@ -1441,6 +1441,41 @@ bool simple_error_example() {
 #include "simdjson.h"
 #include <iostream>
 
+  void scan_json_object_keys() {
+    auto json = R"({"price": 123.456789, "volume": 9999,
+                    "timestamp": "2025-09-04T09:45:00Z",
+                    "symbol": "XYZ", "currency": "USD", "change": 1.23,
+                    "isActive": true})"_padded;
+
+    simdjson::ondemand::parser parser;
+    simdjson::ondemand::document doc = parser.iterate(json);
+
+    for(auto keyvalue : doc.get_object()) {
+        simdjson::ondemand::raw_json_string key = keyvalue.key();
+        switch(key[0]) {
+            case 'p': // price
+                if (key == "price") {
+                    std::string_view price_str = keyvalue.value().raw_json();
+                    std::cout << "Price: " << price_str << std::endl;
+                }
+                break;
+            case 'v': // volume
+                if (key == "volume") {
+                    std::string_view volume_str = keyvalue.value().raw_json();
+                    std::cout << "Volume: " << volume_str << std::endl;
+                }
+                break;
+            case 't': // timestamp
+                if (key == "timestamp") {
+                    std::string_view timestamp = keyvalue.value();
+                    std::cout << "Timestamp: " << timestamp << std::endl;
+                }
+                break;
+            default: break;
+        }
+    }
+  }
+
   // prints the content of the array as hexadecimal 64-bit integers
   void f(simdjson::ondemand::array v) {
     for(uint64_t val : v) {