doc: update link to the TOML spec

doc: recommend to set /Zc:__cplusplus
doc: update section "contributors"
2025-12-16 03:08:52 +08:00 · 2020-09-20 19:24:48 +09:00 · 2020-09-20 18:07:58 +09:00 · 2020-09-19 20:35:37 +09:00 · 2020-09-19 19:08:20 +09:00 · 2020-09-19 18:24:23 +09:00
40 changed files with 1819 additions and 1301 deletions
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -12,7 +12,7 @@ jobs:
          command: |
              g++ --version
              cd tests/
-              g++ -std=c++11 -O2 -Wall -Wextra -Werror -DTOML11_COLORIZE_ERROR_MESSAGE -I../ check_toml_test.cpp -o check_toml_test
+              g++ -std=c++11 -O2 -Wall -Wextra -Werror -DTOML11_DISALLOW_HETEROGENEOUS_ARRAYS -I../ check_toml_test.cpp -o check_toml_test
              go get github.com/BurntSushi/toml-test
              $GOPATH/bin/toml-test ./check_toml_test
  test_serialization:
@@ -24,7 +24,7 @@ jobs:
          command: |
              g++ --version
              cd tests/
-              g++ -std=c++11 -O2 -Wall -Wextra -Wpedantic -Werror -DTOML11_COLORIZE_ERROR_MESSAGE -I../ check_serialization.cpp -o check_serialization
+              g++ -std=c++11 -O2 -Wall -Wextra -Wpedantic -Werror -DTOML11_DISALLOW_HETEROGENEOUS_ARRAYS -I../ check_serialization.cpp -o check_serialization
              git clone https://github.com/BurntSushi/toml-test.git
              cp check_serialization toml-test/tests/valid
              cd toml-test/tests/valid
@@ -47,7 +47,7 @@ jobs:
          command: |
              g++ --version
              cd tests/
-              g++ -std=c++11 -O2 -Wall -Wextra -Wpedantic -Werror -DTOML11_COLORIZE_ERROR_MESSAGE -I../ check.cpp -o check
+              g++ -std=c++11 -O2 -Wall -Wextra -Wpedantic -Werror -DTOML11_DISALLOW_HETEROGENEOUS_ARRAYS -I../ check.cpp -o check
              git clone https://github.com/BurntSushi/toml-test.git
              cp check toml-test/tests/invalid
              cp check toml-test/tests/valid
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -0,0 +1,117 @@
+name: build
+
+on: [push, pull_request]
+
+jobs:
+  build-linux-gcc:
+    runs-on: Ubuntu-18.04
+    strategy:
+      matrix:
+        # g++-4.8 and 4.9 are tested on Travis.CI.
+        compiler: ['g++-9', 'g++-8', 'g++-7', 'g++-6', 'g++-5']
+        standard: ['11', '14', '17', '20']
+        exclude:
+            - {compiler: 'g++-5', standard: '17'}
+            - {compiler: 'g++-6', standard: '17'}
+            - {compiler: 'g++-5', standard: '20'}
+            - {compiler: 'g++-6', standard: '20'}
+            - {compiler: 'g++-7', standard: '20'}
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+        with:
+          submodules: true
+      - name: Install
+        run: |
+            sudo apt-add-repository ppa:mhier/libboost-latest
+            sudo apt-get update
+            sudo apt-get install boost1.70
+            if [[ "${{ matrix.compiler }}" == "g++-6" || "${{ matrix.compiler }}" == "g++-5" ]] ; then
+                sudo apt-add-repository ppa:ubuntu-toolchain-r/test
+                sudo apt-get update
+                sudo apt-get install ${{ matrix.compiler }}
+            fi
+      - name: Configure
+        run: |
+            mkdir build && cd build
+            if [[ "${{ matrix.compiler }}" == "g++-8" && ( "${{ matrix.standard }}" == "17" || "${{ matrix.standard }}" == "20" ) ]] ; then
+                cmake .. -Dtoml11_BUILD_TEST=ON -DCMAKE_CXX_COMPILER=${{ matrix.compiler }} -DCMAKE_CXX_STANDARD=${{ matrix.standard }} -DTOML11_REQUIRE_FILESYSTEM_LIBRARY=ON
+            else
+                cmake .. -Dtoml11_BUILD_TEST=ON -DCMAKE_CXX_COMPILER=${{ matrix.compiler }} -DCMAKE_CXX_STANDARD=${{ matrix.standard }}
+            fi
+      - name: Build
+        run: |
+            cd build && cmake --build .
+      - name: Test
+        run: |
+            cd build && ctest --output-on-failure
+  build-linux-clang:
+    runs-on: Ubuntu-18.04
+    strategy:
+      matrix:
+        compiler: ['10', '9', '8', '7', '6.0', '5.0', '4.0', '3.9']
+        standard: ['11', '14', '17', '20']
+        exclude:
+            - {compiler: '3.9', standard: '17'}
+            - {compiler: '4.0', standard: '17'}
+            - {compiler: '5.0', standard: '17'}
+            - {compiler: '3.9', standard: '20'}
+            - {compiler: '4.0', standard: '20'}
+            - {compiler: '5.0', standard: '20'}
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+        with:
+          submodules: true
+      - name: Install
+        run: |
+            sudo apt-add-repository ppa:mhier/libboost-latest
+            sudo apt-get update
+            sudo apt-get install boost1.70
+            if [[ "${{ matrix.compiler }}" != "6" && "${{ matrix.compiler }}" != "8" && "${{ matrix.compiler }}" != "9" ]] ; then
+                sudo apt-add-repository ppa:ubuntu-toolchain-r/test
+                sudo apt-get update
+                sudo apt-get install clang-${{ matrix.compiler }}
+            fi
+      - name: Configure
+        run: |
+            mkdir build && cd build
+            cmake .. -Dtoml11_BUILD_TEST=ON -DCMAKE_CXX_COMPILER=clang++-${{ matrix.compiler }} -DCMAKE_CXX_STANDARD=${{ matrix.standard }}
+      - name: Build
+        run: |
+            cd build && cmake --build .
+      - name: Test
+        run: |
+            cd build && ctest --output-on-failure
+  build-windows-msvc:
+    runs-on: windows-2019
+    strategy:
+      matrix:
+        standard: ['11', '14', '17', '20']
+        config: ['Release', 'Debug']
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+        with:
+          submodules: true
+      - uses: ilammy/msvc-dev-cmd@v1
+      - name: Configure
+        shell: cmd
+        run: |
+            file --mime-encoding tests/test_literals.cpp
+            mkdir build
+            cd build
+            cmake ../ -G "NMake Makefiles" -Dtoml11_BUILD_TEST=ON -DCMAKE_CXX_STANDARD=${{ matrix.standard }} -DBoost_ADDITIONAL_VERSIONS=1.72.0 -DBoost_USE_MULTITHREADED=ON -DBoost_ARCHITECTURE=-x64 -DBoost_NO_BOOST_CMAKE=ON -DBOOST_ROOT=%BOOST_ROOT_1_72_0%
+      - name: Build
+        working-directory: ./build
+        run: |
+            cmake --build . --config "${{ matrix.config }}"
+      - name: Test
+        working-directory: ./build
+        run: |
+            ./tests/test_literals --log_level=all
+            file --mime-encoding tests/toml/tests/example.toml
+            file --mime-encoding tests/toml/tests/fruit.toml
+            file --mime-encoding tests/toml/tests/hard_example.toml
+            file --mime-encoding tests/toml/tests/hard_example_unicode.toml
+            ctest --build-config "${{ matrix.config }}" --output-on-failure
--- a/.travis.yml
+++ b/.travis.yml
@@ -2,6 +2,30 @@ dist: trusty

 matrix:
  include:
+  - os: linux
+    language: cpp
+    compiler: gcc
+    env: COMPILER="g++-4.8" CXX_STANDARD=11
+    addons:
+      apt:
+        sources:
+        - sourceline: 'ppa:ubuntu-toolchain-r/test'
+        - sourceline: 'ppa:mhier/libboost-latest'
+        packages:
+        - g++-4.8
+        - boost1.70
+  - os: linux
+    language: cpp
+    compiler: gcc
+    env: COMPILER="g++-4.9" CXX_STANDARD=11
+    addons:
+      apt:
+        sources:
+        - sourceline: 'ppa:ubuntu-toolchain-r/test'
+        - sourceline: 'ppa:mhier/libboost-latest'
+        packages:
+        - g++-4.9
+        - boost1.70
  - os: linux
    language: cpp
    compiler: gcc
@@ -77,7 +101,7 @@ matrix:
  - os: linux
    language: cpp
    compiler: gcc
-    env: COMPILER="g++-8" CXX_STANDARD=17
+    env: COMPILER="g++-8" CXX_STANDARD=17 REQUIRE_FILESYSTEM_LIBRARY=ON
    addons:
      apt:
        sources:
@@ -89,7 +113,7 @@ matrix:
  - os: linux
    language: cpp
    compiler: gcc
-    env: COMPILER="g++-8" CXX_STANDARD=17 TOML_HEAD=ON
+    env: COMPILER="g++-8" CXX_STANDARD=17 TOML_HEAD=ON REQUIRE_FILESYSTEM_LIBRARY=ON
    addons:
      apt:
        sources:
@@ -213,7 +237,7 @@ matrix:
  - os: linux
    language: cpp
    compiler: clang
-    env: COMPILER="clang++-8" CXX_STANDARD=17
+    env: COMPILER="clang++-8" CXX_STANDARD=17 REQUIRE_FILESYSTEM_LIBRARY=ON
    addons:
      apt:
        sources:
@@ -227,7 +251,7 @@ matrix:
  - os: linux
    language: cpp
    compiler: clang
-    env: COMPILER="clang++-8" CXX_STANDARD=17 TOML_HEAD=ON
+    env: COMPILER="clang++-8" CXX_STANDARD=17 TOML_HEAD=ON REQUIRE_FILESYSTEM_LIBRARY=ON
    addons:
      apt:
        sources:
@@ -269,16 +293,6 @@ matrix:
  - os: osx
    language: cpp
    compiler: clang
-    env: CXX_STANDARD=11
-    cache:
-      directories:
-        - $HOME/Library/Caches/Homebrew
-    addons:
-      homebrew:
-        update: true
-        packages:
-        - cmake
-        - boost

 script:
 - |
@@ -288,6 +302,10 @@ script:
    tar xf cmake-3.14.5-Linux-x86_64.tar.gz -C cmake --strip-components=1
    export PATH=${TRAVIS_BUILD_DIR}/cmake/bin:${PATH}
  fi
+- |
+  if [[ "${CXX_STANDARD}" == "" ]]; then
+      export CXX_STANDARD="11"
+  fi
 - |
  if [[ "${TOML_HEAD}" != "ON" ]]; then
    export TOML_HEAD="OFF"
@@ -303,17 +321,17 @@ script:
    export WITH_UBSAN="OFF"
  fi
 - echo "WITH_UBSAN = ${WITH_UBSAN}"
+- echo "REQUIRE_FILESYSTEM_LIBRARY = ${REQUIRE_FILESYSTEM_LIBRARY}"
+- |
+  if [[ "${REQUIRE_FILESYSTEM_LIBRARY}" != "ON" ]]; then
+    export REQUIRE_FILESYSTEM_LIBRARY="OFF"
+  fi
+- echo "REQUIRE_FILESYSTEM_LIBRARY = ${REQUIRE_FILESYSTEM_LIBRARY}"
 - cmake --version
 - mkdir build
 - cd build
- git clone https://github.com/toml-lang/toml.git
- cmake -DCMAKE_CXX_COMPILER=$COMPILER -DCMAKE_CXX_STANDARD=$CXX_STANDARD -DTOML11_USE_UNRELEASED_TOML_FEATURES=${TOML_HEAD} -Dtoml11_TEST_WITH_ASAN=${WITH_ASAN} -Dtoml11_TEST_WITH_UBSAN=${WITH_UBSAN} ..
+- echo "COMPILER     = ${COMPILER}"
+- echo "CXX_STANDARD = ${CXX_STANDARD}"
+- cmake -DCMAKE_CXX_COMPILER=$COMPILER -DCMAKE_CXX_STANDARD=$CXX_STANDARD -DTOML11_REQUIRE_FILESYSTEM_LIBRARY=${REQUIRE_FILESYSTEM_LIBRARY} -Dtoml11_BUILD_TEST=ON -DTOML11_USE_UNRELEASED_TOML_FEATURES=${TOML_HEAD} -Dtoml11_TEST_WITH_ASAN=${WITH_ASAN} -Dtoml11_TEST_WITH_UBSAN=${WITH_UBSAN} ..
 - make
 - ctest --output-on-failure
-
-# https://stackoverflow.com/a/53331571
-before_cache:
- |
-  if [[ "${TRAVIS_OS_NAME}" == "osx" ]]; then
-    brew cleanup
-  fi
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,16 +1,9 @@
-cmake_minimum_required(VERSION 2.8)
+cmake_minimum_required(VERSION 3.1)
 enable_testing()

-project(toml11)
+project(toml11 VERSION 3.5.0)

-set(toml11_VERSION_MAYOR  3)
-set(toml11_VERSION_MINOR  3)
-set(toml11_VERSION_PATCH  1)
-set(toml11_VERSION
-  "${toml11_VERSION_MAYOR}.${toml11_VERSION_MINOR}.${toml11_VERSION_PATCH}"
-)
-
-option(toml11_BUILD_TEST "Build toml tests" ON)
+option(toml11_BUILD_TEST "Build toml tests" OFF)
 option(toml11_TEST_WITH_ASAN  "use LLVM address sanitizer" OFF)
 option(toml11_TEST_WITH_UBSAN "use LLVM undefined behavior sanitizer" OFF)

@@ -44,6 +37,11 @@ else()
    endif()
 endif()

+if(MSVC)
+    add_definitions("/Zc:__cplusplus") # define __cplusplus value correctly
+    add_definitions("/utf-8")          # enable to use u8"" literal
+endif()
+
 # Set some common directories
 include(GNUInstallDirs)
 set(toml11_install_cmake_dir         ${CMAKE_INSTALL_LIBDIR}/cmake/toml11)
--- a/README.md
+++ b/README.md
@@ -1,6 +1,7 @@
 toml11
 ======

+[![Build Status on GitHub Actions](https://github.com/ToruNiina/toml11/workflows/build/badge.svg)](https://github.com/ToruNiina/toml11/actions)
 [![Build Status on TravisCI](https://travis-ci.org/ToruNiina/toml11.svg?branch=master)](https://travis-ci.org/ToruNiina/toml11)
 [![Build status on Appveyor](https://ci.appveyor.com/api/projects/status/m2n08a926asvg5mg/branch/master?svg=true)](https://ci.appveyor.com/project/ToruNiina/toml11/branch/master)
 [![Build status on CircleCI](https://circleci.com/gh/ToruNiina/toml11/tree/master.svg?style=svg)](https://circleci.com/gh/ToruNiina/toml11/tree/master)
@@ -8,16 +9,16 @@ toml11
 [![License](https://img.shields.io/github/license/ToruNiina/toml11.svg?style=flat)](LICENSE)
 [![DOI](https://zenodo.org/badge/DOI/10.5281/zenodo.1209136.svg)](https://doi.org/10.5281/zenodo.1209136)

-toml11 is a C++11 header-only toml parser/encoder depending only on C++ standard library.
+toml11 is a C++11 (or later) header-only toml parser/encoder depending only on C++ standard library.

-compatible to the latest version of
-[TOML v0.5.0](https://github.com/toml-lang/toml/blob/master/versions/en/toml-v0.5.0.md)
-after version 2.0.0.
-
-It passes [the language agnostic test suite for TOML parsers by BurntSushi](https://github.com/BurntSushi/toml-test).
-Not only the test suite itself, a TOML reader/encoder also runs on [CircleCI](https://circleci.com/gh/ToruNiina/toml11).
-You can see the error messages about invalid files and serialization results of valid files at
-[CircleCI](https://circleci.com/gh/ToruNiina/toml11).
+- It is compatible to the latest version of [TOML v1.0.0-rc.2](https://toml.io/en/v1.0.0-rc.2).
+- It is one of the most TOML standard compliant libraries, tested with [the language agnostic test suite for TOML parsers by BurntSushi](https://github.com/BurntSushi/toml-test).
+- It shows highly informative error messages. You can see the error messages about invalid files at [CircleCI](https://circleci.com/gh/ToruNiina/toml11).
+- It has configurable container. You can use any random-access containers and key-value maps as backend containers.
+- It optionally preserves comments without any overhead.
+- It has configurable serializer that supports comments, inline tables, literal strings and multiline strings.
+- It supports user-defined type conversion from/into toml values.
+- It correctly handles UTF-8 sequences, with or without BOM, both on posix and Windows.

 ## Example

@@ -27,15 +28,25 @@ You can see the error messages about invalid files and serialization results of

 int main()
 {
-    const auto data = toml::parse("example.toml");
+    auto data = toml::parse("example.toml");

-    // title = "an example toml file"
+    // find a value with the specified type from a table
    std::string title = toml::find<std::string>(data, "title");
-    std::cout << "the title is " << title << std::endl;

-    // nums = [1, 2, 3, 4, 5]
-    std::vector<int> nums  = toml::find<std::vector<int>>(data, "nums");
-    std::cout << "the length of `nums` is" << nums.size() << std::endl;
+    // convert the whole array into any container automatically
+    std::vector<int> nums = toml::find<std::vector<int>>(data, "nums");
+
+    // access with STL-like manner
+    if(not data.at("a").contains("b"))
+    {
+        data["a"]["b"] = "c";
+    }
+
+    // pass a fallback
+    std::string name = toml::find_or<std::string>(data, "name", "not found");
+
+    // width-dependent formatting
+    std::cout << std::setw(80) << data << std::endl;

    return 0;
 }
@@ -84,7 +95,7 @@ int main()
 Just include the file after adding it to the include path.

 ```cpp
-#include <toml11/toml.hpp> // that's all! now you can use it.
+#include <toml.hpp> // that's all! now you can use it.
 #include <iostream>

 int main()
@@ -99,6 +110,8 @@ int main()
 The convenient way is to add this repository as a git-submodule or to install
 it in your system by CMake.

+Note for MSVC: We recommend to set `/Zc:__cplusplus` to detect C++ version correctly.
+
 ## Decoding a toml file

 To parse a toml file, the only thing you have to do is
@@ -109,6 +122,9 @@ const std::string fname("sample.toml");
 const toml::value data = toml::parse(fname);
 ```

+As required by the TOML specification, the top-level value is always a table.
+You can find a value inside it, cast it into a table explicitly, and insert it as a value into other `toml::value`.
+
 If it encounters an error while opening a file, it will throw `std::runtime_error`.

 You can also pass a `std::istream` to the  `toml::parse` function.
@@ -166,7 +182,7 @@ what(): [error] bad time: should be HH:MM:SS.subsec
 --> ./datetime-malformed-no-secs.toml
 1 | no-secs = 1987-07-05T17:45Z
   |                     ^------- HH:MM:SS.subsec
-   | 
+   |
 Hint: pass: 1979-05-27T07:32:00, 1979-05-27 07:32:00.999999
 Hint: fail: 1979-05-27T7:32:00, 1979-05-27 17:32
 ```
@@ -256,11 +272,11 @@ shape = "round"
 ``` cpp
 const auto  data  = toml::parse("fruit.toml");
 const auto& fruit = toml::find(data, "fruit");
-const auto  name  = toml::find<std::string>(fruit, "apple");
+const auto  name  = toml::find<std::string>(fruit, "name");

 const auto& physical = toml::find(fruit, "physical");
-const auto  color    = toml::find<std::string>(fruit, "color");
-const auto  shape    = toml::find<std::string>(fruit, "shape");
+const auto  color    = toml::find<std::string>(physical, "color");
+const auto  shape    = toml::find<std::string>(physical, "shape");
 ```

 Here, variable `fruit` is a `toml::value` and can be used as the first argument
@@ -452,6 +468,24 @@ if(answer.is_integer() && answer.as_integer(std::nothrow) == 42)

 If `std::nothrow` is passed, the functions are marked as noexcept.

+By casting a `toml::value` into an array or a table, you can iterate over the
+elements.
+
+```cpp
+const auto data = toml::parse("example.toml");
+std::cout << "keys in the top-level table are the following: \n";
+for(const auto& [k, v] : data.as_table())
+{
+    std::cout << k << '\n';
+}
+
+const auto& fruits = toml::find(data, "fruits");
+for(const auto& v : fruits.as_array())
+{
+    std::cout << toml::find<std::string>(v, "name") << '\n';
+}
+```
+
 The full list of the functions is below.

 ```cpp
@@ -1413,7 +1447,7 @@ const toml::source_location loc = v.location();

 ## Exceptions

-All the exceptions thrown by toml11 inherits `toml::exception` that inherits
+The following `exception` classes inherits `toml::exception` that inherits
 `std::exception`.

 ```cpp
@@ -1440,6 +1474,16 @@ struct exception : public std::exception

 It represents where the error occurs.

+`syntax_error` will be thrown from `toml::parse` and `_toml` literal.
+`type_error` will be thrown from `toml::get/find`, `toml::value::as_xxx()`, and
+other functions that takes a content inside of `toml::value`.
+
+Note that, currently, from `toml::value::at()` and `toml::find(value, key)`
+may throw an `std::out_of_range` that does not inherits `toml::exception`.
+
+Also, in some cases, most likely in the file open error, it will throw an
+`std::runtime_error`.
+
 ## Colorize Error Messages

 By defining `TOML11_COLORIZE_ERROR_MESSAGE`, the error messages from
@@ -1631,13 +1675,8 @@ not capable of representing a Local Time independent from a specific day.

 ## Unreleased TOML features

-There are some unreleased features in toml-lang/toml:master.
-Currently, the following features are available after defining
-`TOML11_USE_UNRELEASED_TOML_FEATURES` macro flag.
-
-To use those features, `#define` `TOML11_USE_UNRELEASED_TOML_FEATURES` before
-including `toml.hpp` or pass `-DTOML11_USE_UNRELEASED_TOML_FEATURES` to your
-compiler.
+Since TOML v1.0.0-rc.1 has been released, those features are now activated by
+default. We no longer need to define `TOML11_USE_UNRELEASED_FEATURES`.

 - Leading zeroes in exponent parts of floats are permitted.
  - e.g. `1.0e+01`, `5e+05`
@@ -1647,10 +1686,10 @@ compiler.
 - Allow heterogeneous arrays
  - [toml-lang/toml/PR/676](https://github.com/toml-lang/toml/pull/676)

-### Note about heterogeneous arrays
+## Note about heterogeneous arrays

 Although `toml::parse` allows heterogeneous arrays, constructor of `toml::value`
-does not.
+does not. Here the reason is explained.

 ```cpp
 // this won't be compiled
@@ -1659,8 +1698,10 @@ toml::value v{
 }
 ```

-There is a workaround for this issue. By explicitly converting values into
+There is a workaround for this. By explicitly converting values into
 `toml::value`, you can initialize `toml::value` with a heterogeneous array.
+Also, you can first initialize a `toml::value` with an array and then
+`push_back` into it.

 ```cpp
 // OK!
@@ -1668,6 +1709,17 @@ toml::value v{
    toml::value("foo"), toml::value(3.14), toml::value(42),
    toml::value{1,2,3,4,5}, toml::value{{"key", "value"}}
 }
+
+// OK!
+toml::value v(toml::array{});
+v.push_back("foo");
+v.push_back(3.14);
+
+// OK!
+toml::array a;
+a.push_back("foo");
+a.push_back(3.14);
+toml::value v(std::move(a));
 ```

 The reason why the first example is not allowed is the following.
@@ -1696,15 +1748,14 @@ This means that the above C++ code makes constructor's overload resolution
 ambiguous. So a constructor that allows both "table as an initializer-list" and
 "heterogeneous array as an initializer-list" cannot be implemented.

-Thus, although it is painful, you need to explicitly cast values into
-`toml::value` when you initialize heterogeneous array in C++ code.
+Thus, although it is painful, we need to explicitly cast values into
+`toml::value` when you initialize heterogeneous array in a C++ code.

 ```cpp
-// You need to do this when you want to initialize hetero array.
 toml::value v{
    toml::value("foo"), toml::value(3.14), toml::value(42),
    toml::value{1,2,3,4,5}, toml::value{{"key", "value"}}
-}
+};
 ```

 ## Breaking Changes from v2
@@ -1743,14 +1794,13 @@ Such a big change will not happen in the coming years.

 ## Running Tests

-To run test codes, you need to clone toml-lang/toml repository under `build/` directory
-because some of the test codes read a file in the repository.
+After cloning this repository, run the following command (thank you @jwillikers
+for automating test set fetching!).

 ```sh
 $ mkdir build
 $ cd build
-$ git clone https://github.com/toml-lang/toml.git
-$ cmake ..
+$ cmake .. -Dtoml11_BUILD_TEST=ON
 $ make
 $ make test
 ```
@@ -1787,6 +1837,18 @@ I appreciate the help of the contributors who introduced the great feature to th
  - Fixed clang range-loop-analysis warnings
  - Fixed feature test macro to suppress -Wundef
  - Use cache variables in CMakeLists.txt
+  - Automate test set fetching, update and refactor CMakeLists.txt
+- Scott McCaskill
+  - Parse 9 digits (nanoseconds) of fractional seconds in a `local_time`
+- Shu Wang (@halfelf)
+  - fix "Finding a value in an array" example in README
+- @maass-tv and @SeverinLeonhardt
+  - Fix MSVC warning C4866
+- OGAWA KenIchi (@kenichiice)
+  - Fix include path in README
+- Mohammed Alyousef (@MoAlyousef)
+  - Made testing optional in CMake
+

 ## Licensing terms

--- a/appveyor.yml
+++ b/appveyor.yml
@@ -17,10 +17,9 @@ build_script:
  - cd C:\toml11
  - mkdir build
  - cd build
-  - git clone https://github.com/toml-lang/toml.git
-  - file --mime-encoding toml/tests/hard_example_unicode.toml
-  - cmake -G"%generator%" -DBOOST_ROOT=C:/Libraries/boost_1_69_0 ..
+  - cmake -G"%generator%" -DBOOST_ROOT=C:/Libraries/boost_1_69_0 -Dtoml11_BUILD_TEST=ON ..
  - cmake --build . --config "%configuration%"
+  - file --mime-encoding tests/toml/tests/hard_example_unicode.toml

 test_script:
  - ctest --build-config "%configuration%" --timeout 300 --output-on-failure
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -1,3 +1,12 @@
+include(ExternalProject)
+ExternalProject_Add(toml
+        SOURCE_DIR ${CMAKE_CURRENT_BINARY_DIR}/toml
+        GIT_REPOSITORY https://github.com/toml-lang/toml
+        GIT_TAG v0.5.0
+        CONFIGURE_COMMAND ""
+        BUILD_COMMAND ""
+        INSTALL_COMMAND "")
+
 set(TEST_NAMES
    test_datetime
    test_string
@@ -141,9 +150,46 @@ find_package(Boost COMPONENTS unit_test_framework REQUIRED)
 add_definitions(-DBOOST_TEST_DYN_LINK)
 add_definitions(-DUNITTEST_FRAMEWORK_LIBRARY_EXIST)

+# check which standard library implementation is used. If libstdc++ is used,
+# it will fail to compile. It compiles if libc++ is used.
+include(CheckCXXSourceCompiles)
+check_cxx_source_compiles("
+#include <cstddef>
+#ifdef __GLIBCXX__
+    static_assert(false);
+#endif
+int main() {
+    return 0;
+}" TOML11_WITH_LIBCXX_LIBRARY)
+
+# LLVM 8 requires -lc++fs if compiled with libc++ to use <filesystem>.
+# LLVM 9+ does not require any special library.
+# GCC 8 requires -lstdc++fs. GCC 9+ does not require it.
+#
+# Yes, we can check the version of the compiler used in the current build
+# directly in CMake. But, in most cases, clang build uses libstdc++ as the
+# standard library implementation and it makes the condition complicated.
+# In many environment, the default installed C++ compiler is GCC and libstdc++
+# is installed along with it. In most build on such an environment, even if we
+# chose clang as the C++ compiler, still libstdc++ is used. Checking default
+# gcc version makes the condition complicated.
+# The purpose of this file is to compile tests. We know the environment on which
+# the tests run. We can set this option and, I think, it is easier and better.
+option(TOML11_REQUIRE_FILESYSTEM_LIBRARY "need to link -lstdc++fs or -lc++fs" OFF)
+
 foreach(TEST_NAME ${TEST_NAMES})
    add_executable(${TEST_NAME} ${TEST_NAME}.cpp)
    target_link_libraries(${TEST_NAME} ${Boost_UNIT_TEST_FRAMEWORK_LIBRARY} toml11::toml11)
+
+    # to compile tests with <filesystem>...
+    if(TOML11_REQUIRE_FILESYSTEM_LIBRARY)
+        if(TOML11_WITH_LIBCXX_LIBRARY)
+            target_link_libraries(${TEST_NAME} "c++fs")
+        else()
+            target_link_libraries(${TEST_NAME} "stdc++fs")
+        endif()
+    endif()
+
    target_include_directories(${TEST_NAME} PRIVATE ${Boost_INCLUDE_DIRS})

    if(CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
@@ -158,7 +204,7 @@ foreach(TEST_NAME ${TEST_NAMES})
        endif()
    endif()

-    add_test(NAME ${TEST_NAME} COMMAND ${TEST_NAME} WORKING_DIRECTORY ${PROJECT_BINARY_DIR})
+    add_test(NAME ${TEST_NAME} COMMAND ${TEST_NAME} WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR})

    # Set the PATH to be able to find Boost DLL
    if(WIN32)
@@ -169,8 +215,15 @@ foreach(TEST_NAME ${TEST_NAMES})
    endif()
 endforeach(TEST_NAME)

+
 # this test is to check it compiles. it will not run
 add_executable(test_multiple_translation_unit
               test_multiple_translation_unit_1.cpp
               test_multiple_translation_unit_2.cpp)
 target_link_libraries(test_multiple_translation_unit toml11::toml11)
+
+if(WIN32)
+    add_executable(test_windows test_windows.cpp)
+    target_link_libraries(test_windows toml11::toml11)
+endif()
+
--- a/tests/test_comments.cpp
+++ b/tests/test_comments.cpp
@@ -11,7 +11,7 @@
 BOOST_AUTO_TEST_CASE(test_comment_before)
 {
    {
-        const std::string file = u8R"(
+        const std::string file = R"(
            # comment for a.
            a = 42
            # comment for b.
@@ -24,12 +24,12 @@ BOOST_AUTO_TEST_CASE(test_comment_before)
        const auto& b = toml::find(v, "b");

        BOOST_TEST(a.comments().size()  == 1u);
-        BOOST_TEST(a.comments().front() == u8" comment for a.");
+        BOOST_TEST(a.comments().front() == " comment for a.");
        BOOST_TEST(b.comments().size()  == 1u);
-        BOOST_TEST(b.comments().front() == u8" comment for b.");
+        BOOST_TEST(b.comments().front() == " comment for b.");
    }
    {
-        const std::string file = u8R"(
+        const std::string file = R"(
            # comment for a.
            # another comment for a.
            a = 42
@@ -45,18 +45,18 @@ BOOST_AUTO_TEST_CASE(test_comment_before)
        const auto& b = toml::find(v, "b");

        BOOST_TEST(a.comments().size()  == 2u);
-        BOOST_TEST(a.comments().front() == u8" comment for a.");
-        BOOST_TEST(a.comments().back()  == u8" another comment for a.");
+        BOOST_TEST(a.comments().front() == " comment for a.");
+        BOOST_TEST(a.comments().back()  == " another comment for a.");
        BOOST_TEST(b.comments().size()  == 2u);
-        BOOST_TEST(b.comments().front() == u8" comment for b.");
-        BOOST_TEST(b.comments().back()  == u8" also comment for b.");
+        BOOST_TEST(b.comments().front() == " comment for b.");
+        BOOST_TEST(b.comments().back()  == " also comment for b.");
    }
 }

 BOOST_AUTO_TEST_CASE(test_comment_inline)
 {
    {
-        const std::string file = u8R"(
+        const std::string file = R"(
            a = 42    # comment for a.
            b = "baz" # comment for b.
        )";
@@ -68,12 +68,12 @@ BOOST_AUTO_TEST_CASE(test_comment_inline)
        const auto& b = toml::find(v, "b");

        BOOST_TEST(a.comments().size()  == 1u);
-        BOOST_TEST(a.comments().front() == u8" comment for a.");
+        BOOST_TEST(a.comments().front() == " comment for a.");
        BOOST_TEST(b.comments().size()  == 1u);
-        BOOST_TEST(b.comments().front() == u8" comment for b.");
+        BOOST_TEST(b.comments().front() == " comment for b.");
    }
    {
-        const std::string file = u8R"(
+        const std::string file = R"(
            a = [
                42,
            ] # comment for a.
@@ -90,18 +90,18 @@ BOOST_AUTO_TEST_CASE(test_comment_inline)
        const auto& b0 = b.as_array().at(0);

        BOOST_TEST(a.comments().size()   == 1u);
-        BOOST_TEST(a.comments().front()  == u8" comment for a.");
+        BOOST_TEST(a.comments().front()  == " comment for a.");
        BOOST_TEST(b.comments().size()   == 1u);
-        BOOST_TEST(b.comments().front()  == u8" this is a comment for b.");
+        BOOST_TEST(b.comments().front()  == " this is a comment for b.");
        BOOST_TEST(b0.comments().size()  == 1u);
-        BOOST_TEST(b0.comments().front() == u8" this is not a comment for b, but \"bar\"");
+        BOOST_TEST(b0.comments().front() == " this is not a comment for b, but \"bar\"");
    }
 }

 BOOST_AUTO_TEST_CASE(test_comment_both)
 {
    {
-        const std::string file = u8R"(
+        const std::string file = R"(
            # comment for a.
            a = 42 # inline comment for a.
            # comment for b.
@@ -122,25 +122,25 @@ BOOST_AUTO_TEST_CASE(test_comment_both)
        const auto& c0 = c.as_array().at(0);

        BOOST_TEST(a.comments().size()  == 2u);
-        BOOST_TEST(a.comments().front() == u8" comment for a.");
-        BOOST_TEST(a.comments().back()  == u8" inline comment for a.");
+        BOOST_TEST(a.comments().front() == " comment for a.");
+        BOOST_TEST(a.comments().back()  == " inline comment for a.");
        BOOST_TEST(b.comments().size()  == 2u);
-        BOOST_TEST(b.comments().front() == u8" comment for b.");
-        BOOST_TEST(b.comments().back()  == u8" inline comment for b.");
+        BOOST_TEST(b.comments().front() == " comment for b.");
+        BOOST_TEST(b.comments().back()  == " inline comment for b.");

        BOOST_TEST(c.comments().size()  == 2u);
-        BOOST_TEST(c.comments().front() == u8" comment for c.");
-        BOOST_TEST(c.comments().back()  == u8" another comment for c.");
+        BOOST_TEST(c.comments().front() == " comment for c.");
+        BOOST_TEST(c.comments().back()  == " another comment for c.");

        BOOST_TEST(c0.comments().size()  == 2u);
-        BOOST_TEST(c0.comments().front() == u8" comment for the first element.");
-        BOOST_TEST(c0.comments().back()  == u8" this also.");
+        BOOST_TEST(c0.comments().front() == " comment for the first element.");
+        BOOST_TEST(c0.comments().back()  == " this also.");
    }
 }

 BOOST_AUTO_TEST_CASE(test_discard_comment)
 {
-    const std::string file = u8R"(
+    const std::string file = R"(
        # comment for a.
        a = 42 # inline comment for a.
        # comment for b.
--- a/tests/test_error_detection.cpp
+++ b/tests/test_error_detection.cpp
@@ -80,13 +80,13 @@ BOOST_AUTO_TEST_CASE(test_detect_conflicting_value)

 BOOST_AUTO_TEST_CASE(test_detect_inhomogeneous_array)
 {
-#ifdef TOML11_USE_UNRELEASED_TOML_FEATURES
-    BOOST_TEST_MESSAGE("heterogeneous array will be allowed in the next release");
-#else
+#ifdef TOML11_DISALLOW_HETEROGENEOUS_ARRAYS
    std::istringstream stream(std::string(
            "a = [1, 1.0]\n"
            ));
    BOOST_CHECK_THROW(toml::parse(stream), toml::syntax_error);
+#else
+    BOOST_TEST_MESSAGE("After v1.0.0-rc.1, heterogeneous arrays are allowed");
 #endif
 }

--- a/tests/test_extended_conversions.cpp
+++ b/tests/test_extended_conversions.cpp
@@ -47,8 +47,6 @@ struct qux

 struct foobar
 {
-    foobar() = default; // later we use std::vector<foobar>, default ctor is required.
-
    // via constructor
    explicit foobar(const toml::value& v)
        : a(toml::find<int>(v, "a")), b(toml::find<std::string>(v, "b"))
@@ -137,8 +135,6 @@ struct qux

 struct foobar
 {
-    foobar() = default; // later we use std::vector<foobar>, default ctor is required.
-
    template<typename C, template<typename ...> class M, template<typename ...> class A>
    explicit foobar(const toml::basic_value<C, M, A>& v)
        : a(toml::find<int>(v, "a")), b(toml::find<std::string>(v, "b"))
@@ -488,5 +484,64 @@ BOOST_AUTO_TEST_CASE(test_recursive_conversion)
        BOOST_TEST(foobars.at(2).b == "quux");
        BOOST_TEST(foobars.at(3).b == "foobar");
    }
+
+    // via constructor
+    {
+        const toml::value v{
+                {"0", toml::table{{"a", 42}, {"b", "baz"}}},
+                {"1", toml::table{{"a", 43}, {"b", "qux"}}},
+                {"2", toml::table{{"a", 44}, {"b", "quux"}}},
+                {"3", toml::table{{"a", 45}, {"b", "foobar"}}}
+            };
+
+        {
+            const auto foobars = toml::get<std::map<std::string, extlib::foobar>>(v);
+            BOOST_TEST(foobars.size()  == 4ul);
+            BOOST_TEST(foobars.at("0").a == 42);
+            BOOST_TEST(foobars.at("1").a == 43);
+            BOOST_TEST(foobars.at("2").a == 44);
+            BOOST_TEST(foobars.at("3").a == 45);
+
+            BOOST_TEST(foobars.at("0").b == "baz");
+            BOOST_TEST(foobars.at("1").b == "qux");
+            BOOST_TEST(foobars.at("2").b == "quux");
+            BOOST_TEST(foobars.at("3").b == "foobar");
+        }
+        {
+            const auto foobars = toml::get<std::map<std::string, extlib2::foobar>>(v);
+            BOOST_TEST(foobars.size()  == 4ul);
+            BOOST_TEST(foobars.at("0").a == 42);
+            BOOST_TEST(foobars.at("1").a == 43);
+            BOOST_TEST(foobars.at("2").a == 44);
+            BOOST_TEST(foobars.at("3").a == 45);
+
+            BOOST_TEST(foobars.at("0").b == "baz");
+            BOOST_TEST(foobars.at("1").b == "qux");
+            BOOST_TEST(foobars.at("2").b == "quux");
+            BOOST_TEST(foobars.at("3").b == "foobar");
+        }
+    }
+    {
+        const toml::basic_value<toml::discard_comments, std::map, std::deque>
+            v{
+                {"0", toml::table{{"a", 42}, {"b", "baz"}}},
+                {"1", toml::table{{"a", 43}, {"b", "qux"}}},
+                {"2", toml::table{{"a", 44}, {"b", "quux"}}},
+                {"3", toml::table{{"a", 45}, {"b", "foobar"}}}
+            };
+
+        const auto foobars = toml::get<std::map<std::string, extlib::foobar>>(v);
+        BOOST_TEST(foobars.size()  == 4ul);
+        BOOST_TEST(foobars.at("0").a == 42);
+        BOOST_TEST(foobars.at("1").a == 43);
+        BOOST_TEST(foobars.at("2").a == 44);
+        BOOST_TEST(foobars.at("3").a == 45);
+
+        BOOST_TEST(foobars.at("0").b == "baz");
+        BOOST_TEST(foobars.at("1").b == "qux");
+        BOOST_TEST(foobars.at("2").b == "quux");
+        BOOST_TEST(foobars.at("3").b == "foobar");
+    }
+
 }

--- a/tests/test_lex_aux.hpp
+++ b/tests/test_lex_aux.hpp
@@ -8,7 +8,7 @@
 do {                                                                           \
    const std::string token   (tkn);                                           \
    const std::string expected(expct);                                         \
-    toml::detail::location<std::string> loc("test", token);                    \
+    toml::detail::location loc("test", token);                                 \
    const auto result = lxr::invoke(loc);                                      \
    BOOST_TEST(result.is_ok());                                                \
    if(result.is_ok()){                                                        \
@@ -28,7 +28,7 @@ do {                                                                           \
 #define TOML11_TEST_LEX_REJECT(lxr, tkn)                                       \
 do {                                                                           \
    const std::string token   (tkn);                                           \
-    toml::detail::location<std::string> loc("test", token);                    \
+    toml::detail::location loc("test", token);                                 \
    const auto result = lxr::invoke(loc);                                      \
    BOOST_TEST(result.is_err());                                               \
    const bool loc_same = (loc.begin() == loc.iter());                         \
--- a/tests/test_lex_key_comment.cpp
+++ b/tests/test_lex_key_comment.cpp
@@ -18,12 +18,11 @@ BOOST_AUTO_TEST_CASE(test_quoted_key)
 {
    TOML11_TEST_LEX_ACCEPT(lex_key, "\"127.0.0.1\"", "\"127.0.0.1\"");
    TOML11_TEST_LEX_ACCEPT(lex_key, "\"character encoding\"", "\"character encoding\"");
-#if defined(_MSC_VER) || defined(__INTEL_COMPILER)
+
+    // UTF-8 codepoint of characters that looks like "key" written upside down
    TOML11_TEST_LEX_ACCEPT(lex_key, "\"\xCA\x8E\xC7\x9D\xCA\x9E\"",
                                    "\"\xCA\x8E\xC7\x9D\xCA\x9E\"");
-#else
-    TOML11_TEST_LEX_ACCEPT(lex_key, u8"\"ʎǝʞ\"", u8"\"ʎǝʞ\"");
-#endif
+
    TOML11_TEST_LEX_ACCEPT(lex_key, "'key2'", "'key2'");
    TOML11_TEST_LEX_ACCEPT(lex_key, "'quoted \"value\"'", "'quoted \"value\"'");
 }
--- a/tests/test_lex_string.cpp
+++ b/tests/test_lex_string.cpp
@@ -31,15 +31,9 @@ BOOST_AUTO_TEST_CASE(test_basic_string)
            "\"192.168.1.1\"",
            "\"192.168.1.1\"");

-#if defined(_MSC_VER) || defined(__INTEL_COMPILER)
    TOML11_TEST_LEX_ACCEPT(lex_string,
-            "\"\xE4\xB8\xAD\xE5\x9B\xBD\"",
-            "\"\xE4\xB8\xAD\xE5\x9B\xBD\"");
-#else
-    TOML11_TEST_LEX_ACCEPT(lex_string,
-            u8"\"中国\"",
-            u8"\"中国\"");
-#endif
+            "\"\xE4\xB8\xAD\xE5\x9B\xBD\"",  // UTF-8 string (means "China" in
+            "\"\xE4\xB8\xAD\xE5\x9B\xBD\""); // Chinese characters)

    TOML11_TEST_LEX_ACCEPT(lex_string,
            "\"You'll hate me after this - #\"",
--- a/tests/test_literals.cpp
+++ b/tests/test_literals.cpp
@@ -12,6 +12,170 @@ BOOST_AUTO_TEST_CASE(test_file_as_literal)
 {
    using namespace toml::literals::toml_literals;

+    {
+        const toml::value r{{"a", 42}, {"b", "baz"}};
+        const toml::value v = R"(
+            a = 42
+            b = "baz"
+        )"_toml;
+
+        BOOST_TEST(r == v);
+    }
+    {
+        const toml::value r{
+            {"c", 3.14},
+            {"table", toml::table{{"a", 42}, {"b", "baz"}}}
+        };
+        const toml::value v = R"(
+            c = 3.14
+            [table]
+            a = 42
+            b = "baz"
+        )"_toml;
+
+        BOOST_TEST(r == v);
+    }
+    {
+        const toml::value r{
+            {"table", toml::table{{"a", 42}, {"b", "baz"}}}
+        };
+        const toml::value v = R"(
+            [table]
+            a = 42
+            b = "baz"
+        )"_toml;
+
+        BOOST_TEST(r == v);
+    }
+    {
+        const toml::value r{
+            {"array_of_tables", toml::array{toml::table{}}}
+        };
+        const toml::value v = R"(
+            [[array_of_tables]]
+        )"_toml;
+
+        BOOST_TEST(r == v);
+    }
+}
+
+BOOST_AUTO_TEST_CASE(test_value_as_literal)
+{
+    using namespace toml::literals::toml_literals;
+
+    {
+        const toml::value v1 = "true"_toml;
+        const toml::value v2 = "false"_toml;
+
+        BOOST_TEST(v1.is_boolean());
+        BOOST_TEST(v2.is_boolean());
+        BOOST_TEST(toml::get<bool>(v1));
+        BOOST_TEST(!toml::get<bool>(v2));
+    }
+    {
+        const toml::value v1 = "123_456"_toml;
+        const toml::value v2 = "0b0010"_toml;
+        const toml::value v3 = "0xDEADBEEF"_toml;
+
+        BOOST_TEST(v1.is_integer());
+        BOOST_TEST(v2.is_integer());
+        BOOST_TEST(v3.is_integer());
+        BOOST_TEST(toml::get<toml::integer>(v1) == 123456);
+        BOOST_TEST(toml::get<toml::integer>(v2) == 2);
+        BOOST_TEST(toml::get<toml::integer>(v3) == 0xDEADBEEF);
+    }
+    {
+        const toml::value v1 = "3.1415"_toml;
+        const toml::value v2 = "6.02e+23"_toml;
+
+        BOOST_TEST(v1.is_floating());
+        BOOST_TEST(v2.is_floating());
+        BOOST_TEST(toml::get<double>(v1) == 3.1415,  boost::test_tools::tolerance(0.00001));
+        BOOST_TEST(toml::get<double>(v2) == 6.02e23, boost::test_tools::tolerance(0.0001));
+    }
+    {
+        const toml::value v1 = R"("foo")"_toml;
+        const toml::value v2 = R"('foo')"_toml;
+        const toml::value v3 = R"("""foo""")"_toml;
+        const toml::value v4 = R"('''foo''')"_toml;
+
+        BOOST_TEST(v1.is_string());
+        BOOST_TEST(v2.is_string());
+        BOOST_TEST(v3.is_string());
+        BOOST_TEST(v4.is_string());
+        BOOST_TEST(toml::get<std::string>(v1) == "foo");
+        BOOST_TEST(toml::get<std::string>(v2) == "foo");
+        BOOST_TEST(toml::get<std::string>(v3) == "foo");
+        BOOST_TEST(toml::get<std::string>(v4) == "foo");
+    }
+    {
+        {
+            const toml::value v1 = R"([1,2,3])"_toml;
+            BOOST_TEST(v1.is_array());
+            const bool result = (toml::get<std::vector<int>>(v1) == std::vector<int>{1,2,3});
+            BOOST_TEST(result);
+        }
+        {
+            const toml::value v2 = R"([1,])"_toml;
+            BOOST_TEST(v2.is_array());
+            const bool result = (toml::get<std::vector<int>>(v2) == std::vector<int>{1});
+            BOOST_TEST(result);
+        }
+        {
+            const toml::value v3 = R"([[1,]])"_toml;
+            BOOST_TEST(v3.is_array());
+            const bool result = (toml::get<std::vector<int>>(toml::get<toml::array>(v3).front()) == std::vector<int>{1});
+            BOOST_TEST(result);
+        }
+        {
+            const toml::value v4 = R"([[1],])"_toml;
+            BOOST_TEST(v4.is_array());
+            const bool result = (toml::get<std::vector<int>>(toml::get<toml::array>(v4).front()) == std::vector<int>{1});
+            BOOST_TEST(result);
+        }
+    }
+    {
+        const toml::value v1 = R"({a = 42})"_toml;
+
+        BOOST_TEST(v1.is_table());
+        const bool result = toml::get<std::map<std::string,int>>(v1) ==
+                               std::map<std::string,int>{{"a", 42}};
+        BOOST_TEST(result);
+    }
+    {
+        const toml::value v1 = "1979-05-27"_toml;
+
+        BOOST_TEST(v1.is_local_date());
+        BOOST_TEST(toml::get<toml::local_date>(v1) ==
+                   toml::local_date(1979, toml::month_t::May, 27));
+    }
+    {
+        const toml::value v1 = "12:00:00"_toml;
+
+        BOOST_TEST(v1.is_local_time());
+        const bool result = toml::get<std::chrono::hours>(v1) == std::chrono::hours(12);
+        BOOST_TEST(result);
+    }
+    {
+        const toml::value v1 = "1979-05-27T07:32:00"_toml;
+        BOOST_TEST(v1.is_local_datetime());
+        BOOST_TEST(toml::get<toml::local_datetime>(v1) ==
+            toml::local_datetime(toml::local_date(1979, toml::month_t::May, 27),
+                                 toml::local_time(7, 32, 0)));
+    }
+    {
+        const toml::value v1 = "1979-05-27T07:32:00Z"_toml;
+        BOOST_TEST(v1.is_offset_datetime());
+        BOOST_TEST(toml::get<toml::offset_datetime>(v1) ==
+            toml::offset_datetime(toml::local_date(1979, toml::month_t::May, 27),
+                                  toml::local_time(7, 32, 0), toml::time_offset(0, 0)));
+    }
+}
+
+BOOST_AUTO_TEST_CASE(test_file_as_u8_literal)
+{
+    using namespace toml::literals::toml_literals;
+
    {
        const toml::value r{{"a", 42}, {"b", "baz"}};
        const toml::value v = u8R"(
@@ -59,7 +223,7 @@ BOOST_AUTO_TEST_CASE(test_file_as_literal)
    }
 }

-BOOST_AUTO_TEST_CASE(test_value_as_literal)
+BOOST_AUTO_TEST_CASE(test_value_as_u8_literal)
 {
    using namespace toml::literals::toml_literals;

@@ -98,15 +262,18 @@ BOOST_AUTO_TEST_CASE(test_value_as_literal)
        const toml::value v2 = u8R"('foo')"_toml;
        const toml::value v3 = u8R"("""foo""")"_toml;
        const toml::value v4 = u8R"('''foo''')"_toml;
+        const toml::value v5 = u8R"("ひらがな")"_toml;

        BOOST_TEST(v1.is_string());
        BOOST_TEST(v2.is_string());
        BOOST_TEST(v3.is_string());
        BOOST_TEST(v4.is_string());
+        BOOST_TEST(v5.is_string());
        BOOST_TEST(toml::get<std::string>(v1) == "foo");
        BOOST_TEST(toml::get<std::string>(v2) == "foo");
        BOOST_TEST(toml::get<std::string>(v3) == "foo");
        BOOST_TEST(toml::get<std::string>(v4) == "foo");
+        BOOST_TEST(toml::get<std::string>(v5) == "\xE3\x81\xB2\xE3\x82\x89\xE3\x81\x8C\xE3\x81\xAA");
    }
    {
        {
@@ -164,7 +331,7 @@ BOOST_AUTO_TEST_CASE(test_value_as_literal)
                                 toml::local_time(7, 32, 0)));
    }
    {
-        const toml::value v1 = "1979-05-27T07:32:00Z"_toml;
+        const toml::value v1 = u8"1979-05-27T07:32:00Z"_toml;
        BOOST_TEST(v1.is_offset_datetime());
        BOOST_TEST(toml::get<toml::offset_datetime>(v1) ==
            toml::offset_datetime(toml::local_date(1979, toml::month_t::May, 27),
--- a/tests/test_parse_array.cpp
+++ b/tests/test_parse_array.cpp
@@ -172,3 +172,18 @@ BOOST_AUTO_TEST_CASE(test_heterogeneous_array)
    }
 #endif
 }
+
+BOOST_AUTO_TEST_CASE(test_comments_after_comma)
+{
+    {
+        array a;
+        a.push_back("foo");
+        a.push_back("bar");
+        a.push_back("baz");
+        TOML11_TEST_PARSE_EQUAL_VALUE(parse_value<toml::value>,
+            "[ \"foo\" # comment\n"
+            ", \"bar\" # comment\n"
+            ", \"baz\" # comment\n"
+            "]", toml::value(a));
+    }
+}
--- a/tests/test_parse_aux.hpp
+++ b/tests/test_parse_aux.hpp
@@ -7,7 +7,7 @@
 #define TOML11_TEST_PARSE_EQUAL(psr, tkn, expct)                               \
 do {                                                                           \
    const std::string token(tkn);                                              \
-    toml::detail::location<std::string> loc("test", token);                    \
+    toml::detail::location loc("test", token);                                 \
    const auto result = psr(loc);                                              \
    BOOST_TEST(result.is_ok());                                                \
    if(result.is_ok()){                                                        \
@@ -23,7 +23,7 @@ do {                                                                           \
 #define TOML11_TEST_PARSE_EQUAL_VALUE(psr, tkn, expct)                         \
 do {                                                                           \
    const std::string token(tkn);                                              \
-    toml::detail::location<std::string> loc("test", token);                    \
+    toml::detail::location loc("test", token);                                 \
    const auto result = psr(loc);                                              \
    BOOST_TEST(result.is_ok());                                                \
    if(result.is_ok()){                                                        \
--- a/tests/test_parse_file.cpp
+++ b/tests/test_parse_file.cpp
@@ -76,7 +76,7 @@ BOOST_AUTO_TEST_CASE(test_example)

 BOOST_AUTO_TEST_CASE(test_example_stream)
 {
-    std::ifstream ifs("toml/tests/example.toml");
+    std::ifstream ifs("toml/tests/example.toml", std::ios::binary);
    const auto data = toml::parse(ifs);

    BOOST_TEST(toml::find<std::string>(data, "title") == "TOML Example");
@@ -779,6 +779,22 @@ BOOST_AUTO_TEST_CASE(test_files_end_with_empty_lines)
        BOOST_TEST(toml::find<std::string>(toml::find(data, "table"), "key") == "value");
    }

+    // without newline
+    {
+        const std::string table(
+            "key = \"value\"\n"
+            "[table]\n"
+            "key = \"value\"\n"
+            "a = 0"
+            );
+        std::istringstream iss(table);
+        const auto data = toml::parse(iss,
+                "test_files_end_with_newline.toml");
+
+        BOOST_TEST(toml::find<std::string>(data, "key") == "value");
+        BOOST_TEST(toml::find<std::string>(toml::find(data, "table"), "key") == "value");
+    }
+

    // CRLF

@@ -889,3 +905,41 @@ BOOST_AUTO_TEST_CASE(test_files_end_with_empty_lines)
    }
 }

+
+BOOST_AUTO_TEST_CASE(test_parse_function_compiles)
+{
+    // toml::parse("");
+    const auto string_literal = toml::parse("toml/tests/example.toml");
+
+    BOOST_TEST_MESSAGE("string_literal");
+
+    const char* fname_cstring = "toml/tests/example.toml";
+    // toml::parse(const char*);
+    const auto cstring = toml::parse(fname_cstring);
+
+    BOOST_TEST_MESSAGE("const char*");
+
+    // toml::parse(char*);
+    std::array<char, 24> fname_char_ptr;
+    std::strncpy(fname_char_ptr.data(), fname_cstring, 24);
+    const auto char_ptr = toml::parse(fname_char_ptr.data());
+
+    BOOST_TEST_MESSAGE("char*");
+
+    // toml::parse(const std::string&);
+    const std::string fname_string("toml/tests/example.toml");
+    const auto string = toml::parse(fname_string);
+    std::string fname_string_mut("toml/tests/example.toml");
+    // toml::parse(std::string&);
+    const auto string_mutref = toml::parse(fname_string_mut);
+    // toml::parse(std::string&&);
+    const auto string_rref = toml::parse(std::move(fname_string_mut));
+
+    BOOST_TEST_MESSAGE("strings");
+
+#ifdef TOML11_HAS_STD_FILESYSTEM
+    const std::filesystem::path fname_path(fname_string.begin(), fname_string.end());
+    const auto filesystem_path = toml::parse(fname_path);
+    BOOST_TEST_MESSAGE("path");
+#endif
+}
--- a/tests/test_parse_floating.cpp
+++ b/tests/test_parse_floating.cpp
@@ -128,7 +128,7 @@ BOOST_AUTO_TEST_CASE(test_inf)
 {
    {
        const std::string token("inf");
-        toml::detail::location<std::string> loc("test", token);
+        toml::detail::location loc("test", token);
        const auto r = parse_floating(loc);
        BOOST_CHECK(r.is_ok());
        BOOST_CHECK(std::isinf(r.unwrap().first));
@@ -136,7 +136,7 @@ BOOST_AUTO_TEST_CASE(test_inf)
    }
    {
        const std::string token("+inf");
-        toml::detail::location<std::string> loc("test", token);
+        toml::detail::location loc("test", token);
        const auto r = parse_floating(loc);
        BOOST_CHECK(r.is_ok());
        BOOST_CHECK(std::isinf(r.unwrap().first));
@@ -144,7 +144,7 @@ BOOST_AUTO_TEST_CASE(test_inf)
    }
    {
        const std::string token("-inf");
-        toml::detail::location<std::string> loc("test", token);
+        toml::detail::location loc("test", token);
        const auto r = parse_floating(loc);
        BOOST_CHECK(r.is_ok());
        BOOST_CHECK(std::isinf(r.unwrap().first));
@@ -156,21 +156,21 @@ BOOST_AUTO_TEST_CASE(test_nan)
 {
    {
        const std::string token("nan");
-        toml::detail::location<std::string> loc("test", token);
+        toml::detail::location loc("test", token);
        const auto r = parse_floating(loc);
        BOOST_CHECK(r.is_ok());
        BOOST_CHECK(std::isnan(r.unwrap().first));
    }
    {
        const std::string token("+nan");
-        toml::detail::location<std::string> loc("test", token);
+        toml::detail::location loc("test", token);
        const auto r = parse_floating(loc);
        BOOST_CHECK(r.is_ok());
        BOOST_CHECK(std::isnan(r.unwrap().first));
    }
    {
        const std::string token("-nan");
-        toml::detail::location<std::string> loc("test", token);
+        toml::detail::location loc("test", token);
        const auto r = parse_floating(loc);
        BOOST_CHECK(r.is_ok());
        BOOST_CHECK(std::isnan(r.unwrap().first));
--- a/tests/test_parse_table.cpp
+++ b/tests/test_parse_table.cpp
@@ -19,7 +19,7 @@ BOOST_AUTO_TEST_CASE(test_normal_table)
        "key2 = 42\n"
        "key3 = 3.14\n"
        );
-    location<std::string> loc("test", table);
+    location loc("test", table);

    const auto result = toml::detail::parse_ml_table<toml::value>(loc);
    BOOST_TEST(result.is_ok());
@@ -36,7 +36,7 @@ BOOST_AUTO_TEST_CASE(test_nested_table)
        "a.b   = \"value\"\n"
        "a.c.d = 42\n"
        );
-    location<std::string> loc("test", table);
+    location loc("test", table);

    const auto result = toml::detail::parse_ml_table<toml::value>(loc);
    BOOST_TEST(result.is_ok());
--- a/tests/test_parse_unicode.cpp
+++ b/tests/test_parse_unicode.cpp
@@ -9,7 +9,6 @@
 #include <iostream>
 #include <fstream>

-#if defined(_MSC_VER) || defined(__INTEL_COMPILER)
 BOOST_AUTO_TEST_CASE(test_hard_example_unicode)
 {
    const auto data = toml::parse("toml/tests/hard_example_unicode.toml");
@@ -40,35 +39,3 @@ BOOST_AUTO_TEST_CASE(test_hard_example_unicode)
    BOOST_CHECK(toml::get<std::vector<std::string>>(bit.at("multi_line_array")) ==
                expected_multi_line_array);
 }
-#else
-BOOST_AUTO_TEST_CASE(test_hard_example_unicode)
-{
-    const auto data = toml::parse("toml/tests/hard_example_unicode.toml");
-
-    const auto the = toml::find<toml::table>(data, "the");
-    BOOST_TEST(toml::get<std::string>(the.at("test_string")) ==
-                      std::string(u8"Ýôú'ℓℓ λáƭè ₥è áƒƭèř ƭλïƨ - #"));
-
-    const auto hard = toml::get<toml::table>(the.at("hard"));
-    const std::vector<std::string> expected_the_hard_test_array{"] ", " # "};
-    BOOST_CHECK(toml::get<std::vector<std::string>>(hard.at("test_array")) ==
-                expected_the_hard_test_array);
-    const std::vector<std::string> expected_the_hard_test_array2{
-            std::string(u8"Tèƨƭ #11 ]ƥřôƲèδ ƭλáƭ"),
-            std::string(u8"Éжƥèřï₥èñƭ #9 ωáƨ á ƨúççèƨƨ")};
-    BOOST_CHECK(toml::get<std::vector<std::string>>(hard.at("test_array2")) ==
-                expected_the_hard_test_array2);
-    BOOST_TEST(toml::get<std::string>(hard.at("another_test_string")) ==
-                      std::string(u8"§á₥è ƭλïñϱ, βúƭ ωïƭλ á ƨƭřïñϱ #"));
-    BOOST_TEST(toml::get<std::string>(hard.at("harder_test_string")) ==
-                      std::string(u8" Âñδ ωλèñ \"'ƨ ářè ïñ ƭλè ƨƭřïñϱ, áℓôñϱ ωïƭλ # \""));
-
-    const auto bit = toml::get<toml::table>(hard.at(std::string(u8"βïƭ#")));
-    BOOST_TEST(toml::get<std::string>(bit.at(std::string(u8"ωλáƭ?"))) ==
-                      std::string(u8"Ýôú δôñ'ƭ ƭλïñƙ ƨô₥è úƨèř ωôñ'ƭ δô ƭλáƭ?"));
-    const std::vector<std::string> expected_multi_line_array{"]"};
-    BOOST_CHECK(toml::get<std::vector<std::string>>(bit.at("multi_line_array")) ==
-                expected_multi_line_array);
-
-}
-#endif
--- a/tests/test_utility.cpp
+++ b/tests/test_utility.cpp
@@ -9,27 +9,24 @@
 #include <vector>
 #include <array>

-BOOST_AUTO_TEST_CASE(test_resize)
+BOOST_AUTO_TEST_CASE(test_try_reserve)
 {
    {
-        typedef std::vector<int>  resizable_type;
-        typedef std::array<int,1> non_resizable_type;
-        BOOST_TEST(toml::detail::has_resize_method<resizable_type>::value);
-        BOOST_TEST(!toml::detail::has_resize_method<non_resizable_type>::value);
+        // since BOOST_TEST is a macro, it cannot handle commas correctly.
+        // When toml::detail::has_reserve_method<std::array<int, 1>>::value
+        // is passed to a macro, C preprocessor considers
+        // toml::detail::has_reserve_method<std::array<int as the first argument
+        // and 1>>::value as the second argument. We need an alias to avoid
+        // this problem.
+        using reservable_type    = std::vector<int>  ;
+        using nonreservable_type = std::array<int, 1>;
+        BOOST_TEST( toml::detail::has_reserve_method<reservable_type   >::value);
+        BOOST_TEST(!toml::detail::has_reserve_method<nonreservable_type>::value);
    }
    {
        std::vector<int> v;
-        toml::resize(v, 10);
-        BOOST_TEST(v.size() == 10u);
-    }
-    {
-        std::array<int, 15> a;
-        toml::resize(a, 10);
-        BOOST_TEST(a.size() == 15u);
-    }
-    {
-        std::array<int, 15> a;
-        BOOST_CHECK_THROW(toml::resize(a, 20), std::invalid_argument);
+        toml::try_reserve(v, 100);
+        BOOST_TEST(v.capacity() == 100u);
    }
 }

--- a/tests/test_windows.cpp
+++ b/tests/test_windows.cpp
@@ -0,0 +1,12 @@
+#include <windows.h>
+#include <toml.hpp>
+#include <iostream>
+
+int main()
+{
+    using namespace toml::literals::toml_literals;
+    const auto data = R"(windows = "defines min and max as a macro")"_toml;
+
+    std::cout << toml::find<std::string>(data, "windows") << std::endl;
+    return 0;
+}
--- a/toml.hpp
+++ b/toml.hpp
@@ -33,6 +33,10 @@
 #    error "toml11 requires C++11 or later."
 #endif

+#define TOML11_VERSION_MAJOR 3
+#define TOML11_VERSION_MINOR 5
+#define TOML11_VERSION_PATCH 0
+
 #include "toml/parser.hpp"
 #include "toml/literal.hpp"
 #include "toml/serializer.hpp"
--- a/toml/color.hpp
+++ b/toml/color.hpp
@@ -1,7 +1,7 @@
 #ifndef TOML11_COLOR_HPP
 #define TOML11_COLOR_HPP
-#include <ostream>
 #include <cstdint>
+#include <ostream>

 #ifdef TOML11_COLORIZE_ERROR_MESSAGE
 #define TOML11_ERROR_MESSAGE_COLORIZED true
--- a/toml/combinator.hpp
+++ b/toml/combinator.hpp
@@ -2,18 +2,20 @@
 // Distributed under the MIT License.
 #ifndef TOML11_COMBINATOR_HPP
 #define TOML11_COMBINATOR_HPP
-#include "traits.hpp"
-#include "result.hpp"
-#include "utility.hpp"
-#include "region.hpp"
-#include <type_traits>
-#include <iterator>
-#include <limits>
-#include <array>
-#include <iomanip>
-#include <cstdio>
 #include <cassert>
 #include <cctype>
+#include <cstdio>
+
+#include <array>
+#include <iomanip>
+#include <iterator>
+#include <limits>
+#include <type_traits>
+
+#include "region.hpp"
+#include "result.hpp"
+#include "traits.hpp"
+#include "utility.hpp"

 // they scans characters and returns region if it matches to the condition.
 // when they fail, it does not change the location.
@@ -56,13 +58,9 @@ struct character
 {
    static constexpr char target = C;

-    template<typename Cont>
-    static result<region<Cont>, none_t>
-    invoke(location<Cont>& loc)
+    static result<region, none_t>
+    invoke(location& loc)
    {
-        static_assert(std::is_same<char, typename Cont::value_type>::value,
-                      "internal error: container::value_type should be `char`.");
-
        if(loc.iter() == loc.end()) {return none();}
        const auto first = loc.iter();

@@ -73,7 +71,7 @@ struct character
        }
        loc.advance(); // update location

-        return ok(region<Cont>(loc, first, loc.iter()));
+        return ok(region(loc, first, loc.iter()));
    }
 };
 template<char C>
@@ -89,13 +87,9 @@ struct in_range
    static constexpr char upper = Up;
    static constexpr char lower = Low;

-    template<typename Cont>
-    static result<region<Cont>, none_t>
-    invoke(location<Cont>& loc)
+    static result<region, none_t>
+    invoke(location& loc)
    {
-        static_assert(std::is_same<char, typename Cont::value_type>::value,
-                      "internal error: container::value_type should be `char`.");
-
        if(loc.iter() == loc.end()) {return none();}
        const auto first = loc.iter();

@@ -106,7 +100,7 @@ struct in_range
        }

        loc.advance();
-        return ok(region<Cont>(loc, first, loc.iter()));
+        return ok(region(loc, first, loc.iter()));
    }
 };
 template<char L, char U> constexpr char in_range<L, U>::upper;
@@ -117,13 +111,9 @@ template<char L, char U> constexpr char in_range<L, U>::lower;
 template<typename Combinator>
 struct exclude
 {
-    template<typename Cont>
-    static result<region<Cont>, none_t>
-    invoke(location<Cont>& loc)
+    static result<region, none_t>
+    invoke(location& loc)
    {
-        static_assert(std::is_same<char, typename Cont::value_type>::value,
-                      "internal error: container::value_type should be `char`.");
-
        if(loc.iter() == loc.end()) {return none();}
        auto first = loc.iter();

@@ -134,7 +124,7 @@ struct exclude
            return none();
        }
        loc.reset(std::next(first)); // XXX maybe loc.advance() is okay but...
-        return ok(region<Cont>(loc, first, loc.iter()));
+        return ok(region(loc, first, loc.iter()));
    }
 };

@@ -142,19 +132,15 @@ struct exclude
 template<typename Combinator>
 struct maybe
 {
-    template<typename Cont>
-    static result<region<Cont>, none_t>
-    invoke(location<Cont>& loc)
+    static result<region, none_t>
+    invoke(location& loc)
    {
-        static_assert(std::is_same<char, typename Cont::value_type>::value,
-                      "internal error: container::value_type should be `char`.");
-
        const auto rslt = Combinator::invoke(loc);
        if(rslt.is_ok())
        {
            return rslt;
        }
-        return ok(region<Cont>(loc));
+        return ok(region(loc));
    }
 };

@@ -164,13 +150,9 @@ struct sequence;
 template<typename Head, typename ... Tail>
 struct sequence<Head, Tail...>
 {
-    template<typename Cont>
-    static result<region<Cont>, none_t>
-    invoke(location<Cont>& loc)
+    static result<region, none_t>
+    invoke(location& loc)
    {
-        static_assert(std::is_same<char, typename Cont::value_type>::value,
-                      "internal error: container::value_type should be `char`.");
-
        const auto first = loc.iter();
        const auto rslt = Head::invoke(loc);
        if(rslt.is_err())
@@ -182,9 +164,9 @@ struct sequence<Head, Tail...>
    }

    // called from the above function only, recursively.
-    template<typename Cont, typename Iterator>
-    static result<region<Cont>, none_t>
-    invoke(location<Cont>& loc, region<Cont> reg, Iterator first)
+    template<typename Iterator>
+    static result<region, none_t>
+    invoke(location& loc, region reg, Iterator first)
    {
        const auto rslt = Head::invoke(loc);
        if(rslt.is_err())
@@ -201,9 +183,9 @@ template<typename Head>
 struct sequence<Head>
 {
    // would be called from sequence<T ...>::invoke only.
-    template<typename Cont, typename Iterator>
-    static result<region<Cont>, none_t>
-    invoke(location<Cont>& loc, region<Cont> reg, Iterator first)
+    template<typename Iterator>
+    static result<region, none_t>
+    invoke(location& loc, region reg, Iterator first)
    {
        const auto rslt = Head::invoke(loc);
        if(rslt.is_err())
@@ -222,13 +204,9 @@ struct either;
 template<typename Head, typename ... Tail>
 struct either<Head, Tail...>
 {
-    template<typename Cont>
-    static result<region<Cont>, none_t>
-    invoke(location<Cont>& loc)
+    static result<region, none_t>
+    invoke(location& loc)
    {
-        static_assert(std::is_same<char, typename Cont::value_type>::value,
-                      "internal error: container::value_type should be `char`.");
-
        const auto rslt = Head::invoke(loc);
        if(rslt.is_ok()) {return rslt;}
        return either<Tail...>::invoke(loc);
@@ -237,12 +215,9 @@ struct either<Head, Tail...>
 template<typename Head>
 struct either<Head>
 {
-    template<typename Cont>
-    static result<region<Cont>, none_t>
-    invoke(location<Cont>& loc)
+    static result<region, none_t>
+    invoke(location& loc)
    {
-        static_assert(std::is_same<char, typename Cont::value_type>::value,
-                      "internal error: container::value_type should be `char`.");
        return Head::invoke(loc);
    }
 };
@@ -257,11 +232,10 @@ struct unlimited{};
 template<typename T, std::size_t N>
 struct repeat<T, exactly<N>>
 {
-    template<typename Cont>
-    static result<region<Cont>, none_t>
-    invoke(location<Cont>& loc)
+    static result<region, none_t>
+    invoke(location& loc)
    {
-        region<Cont> retval(loc);
+        region retval(loc);
        const auto first = loc.iter();
        for(std::size_t i=0; i<N; ++i)
        {
@@ -280,11 +254,10 @@ struct repeat<T, exactly<N>>
 template<typename T, std::size_t N>
 struct repeat<T, at_least<N>>
 {
-    template<typename Cont>
-    static result<region<Cont>, none_t>
-    invoke(location<Cont>& loc)
+    static result<region, none_t>
+    invoke(location& loc)
    {
-        region<Cont> retval(loc);
+        region retval(loc);

        const auto first = loc.iter();
        for(std::size_t i=0; i<N; ++i)
@@ -312,11 +285,10 @@ struct repeat<T, at_least<N>>
 template<typename T>
 struct repeat<T, unlimited>
 {
-    template<typename Cont>
-    static result<region<Cont>, none_t>
-    invoke(location<Cont>& loc)
+    static result<region, none_t>
+    invoke(location& loc)
    {
-        region<Cont> retval(loc);
+        region retval(loc);
        while(true)
        {
            auto rslt = T::invoke(loc);
--- a/toml/comments.hpp
+++ b/toml/comments.hpp
@@ -2,12 +2,12 @@
 // Distributed under the MIT License.
 #ifndef TOML11_COMMENTS_HPP
 #define TOML11_COMMENTS_HPP
+#include <initializer_list>
+#include <iterator>
+#include <string>
 #include <type_traits>
 #include <utility>
-#include <iterator>
-#include <initializer_list>
 #include <vector>
-#include <string>

 // This file provides mainly two classes, `preserve_comments` and `discard_comments`.
 // Those two are a container that have the same interface as `std::vector<std::string>`
@@ -81,6 +81,54 @@ struct preserve_comments
    void assign(std::initializer_list<std::string> ini)  {comments.assign(ini);}
    void assign(size_type n, const std::string& val)     {comments.assign(n, val);}

+    // Related to the issue #97.
+    //
+    // It is known that `std::vector::insert` and `std::vector::erase` in
+    // the standard library implementation included in GCC 4.8.5 takes
+    // `std::vector::iterator` instead of `std::vector::const_iterator`.
+    // Because of the const-correctness, we cannot convert a `const_iterator` to
+    // an `iterator`. It causes compilation error in GCC 4.8.5.
+#if defined(__GNUC__) && defined(__GNUC_MINOR__) && defined(__GNUC_PATCHLEVEL__) && !defined(__clang__)
+#  if (__GNUC__ * 10000 + __GNUC_MINOR__ * 100 + __GNUC_PATCHLEVEL__) <= 40805
+#    define TOML11_WORKAROUND_GCC_4_8_X_STANDARD_LIBRARY_IMPLEMENTATION
+#  endif
+#endif
+
+#ifdef TOML11_WORKAROUND_GCC_4_8_X_STANDARD_LIBRARY_IMPLEMENTATION
+    iterator insert(iterator p, const std::string& x)
+    {
+        return comments.insert(p, x);
+    }
+    iterator insert(iterator p, std::string&&      x)
+    {
+        return comments.insert(p, std::move(x));
+    }
+    void insert(iterator p, size_type n, const std::string& x)
+    {
+        return comments.insert(p, n, x);
+    }
+    template<typename InputIterator>
+    void insert(iterator p, InputIterator first, InputIterator last)
+    {
+        return comments.insert(p, first, last);
+    }
+    void insert(iterator p, std::initializer_list<std::string> ini)
+    {
+        return comments.insert(p, ini);
+    }
+
+    template<typename ... Ts>
+    iterator emplace(iterator p, Ts&& ... args)
+    {
+        return comments.emplace(p, std::forward<Ts>(args)...);
+    }
+
+    iterator erase(iterator pos) {return comments.erase(pos);}
+    iterator erase(iterator first, iterator last)
+    {
+        return comments.erase(first, last);
+    }
+#else
    iterator insert(const_iterator p, const std::string& x)
    {
        return comments.insert(p, x);
@@ -114,6 +162,7 @@ struct preserve_comments
    {
        return comments.erase(first, last);
    }
+#endif

    void swap(preserve_comments& other) {comments.swap(other.comments);}

--- a/toml/datetime.hpp
+++ b/toml/datetime.hpp
@@ -2,15 +2,16 @@
 // Distributed under the MIT License.
 #ifndef TOML11_DATETIME_HPP
 #define TOML11_DATETIME_HPP
-#include <chrono>
-#include <tuple>
-#include <array>
-#include <ostream>
-#include <iomanip>
 #include <cstdint>
 #include <cstdlib>
 #include <ctime>

+#include <array>
+#include <chrono>
+#include <iomanip>
+#include <ostream>
+#include <tuple>
+
 namespace toml
 {

--- a/toml/exception.hpp
+++ b/toml/exception.hpp
@@ -2,10 +2,11 @@
 // Distributed under the MIT License.
 #ifndef TOML11_EXCEPTION_HPP
 #define TOML11_EXCEPTION_HPP
-#include "source_location.hpp"
 #include <stdexcept>
 #include <string>

+#include "source_location.hpp"
+
 namespace toml
 {

--- a/toml/get.hpp
+++ b/toml/get.hpp
@@ -2,10 +2,11 @@
 // Distributed under the MIT License.
 #ifndef TOML11_GET_HPP
 #define TOML11_GET_HPP
+#include <algorithm>
+
 #include "from.hpp"
 #include "result.hpp"
 #include "value.hpp"
-#include <algorithm>

 namespace toml
 {
@@ -188,8 +189,7 @@ get(const basic_value<C, M, V>& v)
        {
            throw type_error(detail::format_underline("toml::value: "
                "bad_cast to std::chrono::system_clock::time_point", {
-                    {std::addressof(detail::get_region(v)),
-                     concat_to_string("the actual type is ", v.type())}
+                    {v.location(), concat_to_string("the actual type is ", v.type())}
                }), v.location());
        }
    }
@@ -198,24 +198,24 @@ get(const basic_value<C, M, V>& v)
 // ============================================================================
 // forward declaration to use this recursively. ignore this and go ahead.

-// array-like type with resize(N) method
+// array-like type with push_back(value) method
 template<typename T, typename C,
         template<typename ...> class M, template<typename ...> class V>
 detail::enable_if_t<detail::conjunction<
-    detail::is_container<T>,      // T is container
-    detail::has_resize_method<T>, // T::resize(N) works
-    detail::negation<             // but not toml::array
+    detail::is_container<T>,         // T is a container
+    detail::has_push_back_method<T>, // T::push_back(value) works
+    detail::negation<                // but not toml::array
        detail::is_exact_toml_type<T, basic_value<C, M, V>>>
    >::value, T>
 get(const basic_value<C, M, V>&);

-// array-like type with resize(N) method
+// array-like type without push_back(value) method
 template<typename T, typename C,
         template<typename ...> class M, template<typename ...> class V>
 detail::enable_if_t<detail::conjunction<
-    detail::is_container<T>,                        // T is container
-    detail::negation<detail::has_resize_method<T>>, // no T::resize() exists
-    detail::negation<                               // not toml::array
+    detail::is_container<T>,                           // T is a container
+    detail::negation<detail::has_push_back_method<T>>, // w/o push_back(...)
+    detail::negation<                                  // not toml::array
        detail::is_exact_toml_type<T, basic_value<C, M, V>>>
    >::value, T>
 get(const basic_value<C, M, V>&);
@@ -274,31 +274,54 @@ get(const basic_value<C, M, V>&);
 template<typename T, typename C,
         template<typename ...> class M, template<typename ...> class V>
 detail::enable_if_t<detail::conjunction<
-    detail::is_container<T>,      // T is container
-    detail::has_resize_method<T>, // T::resize(N) works
-    detail::negation<             // but not toml::array
+    detail::is_container<T>,         // T is a container
+    detail::has_push_back_method<T>, // container.push_back(elem) works
+    detail::negation<                // but not toml::array
        detail::is_exact_toml_type<T, basic_value<C, M, V>>>
    >::value, T>
 get(const basic_value<C, M, V>& v)
 {
    using value_type = typename T::value_type;
-    const auto& ar = v.as_array();
+    const auto& ary = v.as_array();
+
    T container;
-    container.resize(ar.size());
-    std::transform(ar.cbegin(), ar.cend(), container.begin(),
-                   [](const value& x){return ::toml::get<value_type>(x);});
+    try_reserve(container, ary.size());
+
+    for(const auto& elem : ary)
+    {
+        container.push_back(get<value_type>(elem));
+    }
    return container;
 }

 // ============================================================================
-// array-like types; but does not have resize(); most likely std::array.
+// std::forward_list does not have push_back, insert, or emplace.
+// It has insert_after, emplace_after, push_front.
+
+template<typename T, typename C,
+         template<typename ...> class M, template<typename ...> class V>
+detail::enable_if_t<detail::is_std_forward_list<T>::value, T>
+get(const basic_value<C, M, V>& v)
+{
+    using value_type = typename T::value_type;
+    T container;
+    for(const auto& elem : v.as_array())
+    {
+        container.push_front(get<value_type>(elem));
+    }
+    container.reverse();
+    return container;
+}
+
+// ============================================================================
+// array-like types, without push_back(). most likely [std|boost]::array.

 template<typename T, typename C,
         template<typename ...> class M, template<typename ...> class V>
 detail::enable_if_t<detail::conjunction<
-    detail::is_container<T>,                        // T is container
-    detail::negation<detail::has_resize_method<T>>, // no T::resize() exists
-    detail::negation<                              // but not toml::array
+    detail::is_container<T>,                           // T is a container
+    detail::negation<detail::has_push_back_method<T>>, // w/o push_back
+    detail::negation<                                  // T is not toml::array
        detail::is_exact_toml_type<T, basic_value<C, M, V>>>
    >::value, T>
 get(const basic_value<C, M, V>& v)
@@ -312,7 +335,7 @@ get(const basic_value<C, M, V>& v)
        throw std::out_of_range(detail::format_underline(concat_to_string(
            "toml::get: specified container size is ", container.size(),
            " but there are ", ar.size(), " elements in toml array."), {
-                {std::addressof(detail::get_region(v)), "here"}
+                {v.location(), "here"}
            }));
    }
    std::transform(ar.cbegin(), ar.cend(), container.begin(),
@@ -336,9 +359,7 @@ get(const basic_value<C, M, V>& v)
    {
        throw std::out_of_range(detail::format_underline(concat_to_string(
            "toml::get: specified std::pair but there are ", ar.size(),
-            " elements in toml array."), {
-                {std::addressof(detail::get_region(v)), "here"}
-            }));
+            " elements in toml array."), {{v.location(), "here"}}));
    }
    return std::make_pair(::toml::get<first_type >(ar.at(0)),
                          ::toml::get<second_type>(ar.at(1)));
@@ -368,9 +389,7 @@ get(const basic_value<C, M, V>& v)
        throw std::out_of_range(detail::format_underline(concat_to_string(
            "toml::get: specified std::tuple with ",
            std::tuple_size<T>::value, " elements, but there are ", ar.size(),
-            " elements in toml array."), {
-                {std::addressof(detail::get_region(v)), "here"}
-            }));
+            " elements in toml array."), {{v.location(), "here"}}));
    }
    return detail::get_tuple_impl<T>(ar,
            detail::make_index_sequence<std::tuple_size<T>::value>{});
@@ -396,7 +415,7 @@ get(const basic_value<C, M, V>& v)
    T map;
    for(const auto& kv : v.as_table())
    {
-        map[key_type(kv.first)] = ::toml::get<mapped_type>(kv.second);
+        map.emplace(key_type(kv.first), get<mapped_type>(kv.second));
    }
    return map;
 }
@@ -449,10 +468,7 @@ basic_value<C, M, V> const& find(const basic_value<C, M, V>& v, const key& ky)
    const auto& tab = v.as_table();
    if(tab.count(ky) == 0)
    {
-        throw std::out_of_range(detail::format_underline(concat_to_string(
-            "key \"", ky, "\" not found"), {
-                {std::addressof(detail::get_region(v)), "in this table"}
-            }));
+        detail::throw_key_not_found_error(v, ky);
    }
    return tab.at(ky);
 }
@@ -463,10 +479,7 @@ basic_value<C, M, V>& find(basic_value<C, M, V>& v, const key& ky)
    auto& tab = v.as_table();
    if(tab.count(ky) == 0)
    {
-        throw std::out_of_range(detail::format_underline(concat_to_string(
-            "key \"", ky, "\" not found"), {
-                {std::addressof(detail::get_region(v)), "in this table"}
-            }));
+        detail::throw_key_not_found_error(v, ky);
    }
    return tab.at(ky);
 }
@@ -477,10 +490,7 @@ basic_value<C, M, V> find(basic_value<C, M, V>&& v, const key& ky)
    typename basic_value<C, M, V>::table_type tab = std::move(v).as_table();
    if(tab.count(ky) == 0)
    {
-        throw std::out_of_range(detail::format_underline(concat_to_string(
-            "key \"", ky, "\" not found"), {
-                {std::addressof(detail::get_region(v)), "in this table"}
-            }));
+        detail::throw_key_not_found_error(v, ky);
    }
    return basic_value<C, M, V>(std::move(tab.at(ky)));
 }
@@ -496,9 +506,7 @@ find(const basic_value<C, M, V>& v, const std::size_t idx)
    if(ary.size() <= idx)
    {
        throw std::out_of_range(detail::format_underline(concat_to_string(
-            "index ", idx, " is out of range"), {
-                {std::addressof(detail::get_region(v)), "in this array"}
-            }));
+            "index ", idx, " is out of range"), {{v.location(), "in this array"}}));
    }
    return ary.at(idx);
 }
@@ -510,9 +518,7 @@ basic_value<C, M, V>& find(basic_value<C, M, V>& v, const std::size_t idx)
    if(ary.size() <= idx)
    {
        throw std::out_of_range(detail::format_underline(concat_to_string(
-            "index ", idx, " is out of range"), {
-                {std::addressof(detail::get_region(v)), "in this array"}
-            }));
+            "index ", idx, " is out of range"), {{v.location(), "in this array"}}));
    }
    return ary.at(idx);
 }
@@ -524,9 +530,7 @@ basic_value<C, M, V> find(basic_value<C, M, V>&& v, const std::size_t idx)
    if(ary.size() <= idx)
    {
        throw std::out_of_range(detail::format_underline(concat_to_string(
-            "index ", idx, " is out of range"), {
-                {std::addressof(detail::get_region(v)), "in this array"}
-            }));
+            "index ", idx, " is out of range"), {{v.location(), "in this array"}}));
    }
    return basic_value<C, M, V>(std::move(ary.at(idx)));
 }
@@ -542,10 +546,7 @@ find(const basic_value<C, M, V>& v, const key& ky)
    const auto& tab = v.as_table();
    if(tab.count(ky) == 0)
    {
-        throw std::out_of_range(detail::format_underline(concat_to_string(
-            "key \"", ky, "\" not found"), {
-                {std::addressof(detail::get_region(v)), "in this table"}
-            }));
+        detail::throw_key_not_found_error(v, ky);
    }
    return ::toml::get<T>(tab.at(ky));
 }
@@ -558,10 +559,7 @@ find(basic_value<C, M, V>& v, const key& ky)
    auto& tab = v.as_table();
    if(tab.count(ky) == 0)
    {
-        throw std::out_of_range(detail::format_underline(concat_to_string(
-            "key \"", ky, "\" not found"), {
-                {std::addressof(detail::get_region(v)), "in this table"}
-            }));
+        detail::throw_key_not_found_error(v, ky);
    }
    return ::toml::get<T>(tab.at(ky));
 }
@@ -574,10 +572,7 @@ find(basic_value<C, M, V>&& v, const key& ky)
    typename basic_value<C, M, V>::table_type tab = std::move(v).as_table();
    if(tab.count(ky) == 0)
    {
-        throw std::out_of_range(detail::format_underline(concat_to_string(
-            "key \"", ky, "\" not found"), {
-                {std::addressof(detail::get_region(v)), "in this table"}
-            }));
+        detail::throw_key_not_found_error(v, ky);
    }
    return ::toml::get<T>(std::move(tab.at(ky)));
 }
@@ -593,9 +588,7 @@ find(const basic_value<C, M, V>& v, const std::size_t idx)
    if(ary.size() <= idx)
    {
        throw std::out_of_range(detail::format_underline(concat_to_string(
-            "index ", idx, " is out of range"), {
-                {std::addressof(detail::get_region(v)), "in this array"}
-            }));
+            "index ", idx, " is out of range"), {{v.location(), "in this array"}}));
    }
    return ::toml::get<T>(ary.at(idx));
 }
@@ -608,9 +601,7 @@ find(basic_value<C, M, V>& v, const std::size_t idx)
    if(ary.size() <= idx)
    {
        throw std::out_of_range(detail::format_underline(concat_to_string(
-            "index ", idx, " is out of range"), {
-                {std::addressof(detail::get_region(v)), "in this array"}
-            }));
+            "index ", idx, " is out of range"), {{v.location(), "in this array"}}));
    }
    return ::toml::get<T>(ary.at(idx));
 }
@@ -623,9 +614,7 @@ find(basic_value<C, M, V>&& v, const std::size_t idx)
    if(ary.size() <= idx)
    {
        throw std::out_of_range(detail::format_underline(concat_to_string(
-            "index ", idx, " is out of range"), {
-                {std::addressof(detail::get_region(v)), "in this array"}
-            }));
+            "index ", idx, " is out of range"), {{v.location(), "in this array"}}));
    }
    return ::toml::get<T>(std::move(ary.at(idx)));
 }
--- a/toml/lexer.hpp
+++ b/toml/lexer.hpp
@@ -2,12 +2,13 @@
 // Distributed under the MIT License.
 #ifndef TOML11_LEXER_HPP
 #define TOML11_LEXER_HPP
-#include "combinator.hpp"
-#include <stdexcept>
 #include <istream>
 #include <sstream>
+#include <stdexcept>
 #include <fstream>

+#include "combinator.hpp"
+
 namespace toml
 {
 namespace detail
@@ -69,15 +70,8 @@ using lex_zero_prefixable_int = sequence<lex_digit, repeat<either<lex_digit,

 using lex_fractional_part = sequence<character<'.'>, lex_zero_prefixable_int>;

-#ifdef TOML11_USE_UNRELEASED_TOML_FEATURES
-// use toml-lang/toml HEAD
 using lex_exponent_part   = sequence<either<character<'e'>, character<'E'>>,
        maybe<lex_sign>, lex_zero_prefixable_int>;
-#else
-// strictly TOML v0.5.0
-using lex_exponent_part = sequence<either<character<'e'>, character<'E'>>,
-        lex_dec_int>;
-#endif

 using lex_float = either<lex_special_float,
      sequence<lex_dec_int, either<lex_exponent_part,
@@ -125,17 +119,11 @@ using lex_local_time       = lex_partial_time;
 // ===========================================================================

 using lex_quotation_mark  = character<'"'>;
-#ifdef TOML11_USE_UNRELEASED_TOML_FEATURES
 using lex_basic_unescaped = exclude<either<in_range<0x00, 0x08>, // 0x09 (tab)
                                           in_range<0x0a, 0x1F>, // is allowed
                                           character<0x22>, character<0x5C>,
                                           character<0x7F>>>;
-#else
-using lex_basic_unescaped = exclude<either<in_range<0x00, 0x1F>,
-                                           character<0x22>, character<0x5C>,
-                                           character<0x7F>>>;

-#endif
 using lex_escape          = character<'\\'>;
 using lex_escape_unicode_short = sequence<character<'u'>,
                                          repeat<lex_hex_dig, exactly<4>>>;
@@ -183,12 +171,6 @@ using lex_basic_string = sequence<lex_quotation_mark,
 // In parse_ml_basic_string() function, the trailing `"`s will be attached to
 // the string body.
 //
-// Note: This feature is a "clarification". Therefore this change is considered
-//       as a spec that has been defined since the time when the multi-line
-//       basic string was introduced. Although it is a post-v0.5.0 changes,
-//       this change will be activated regardless of the flag,
-//       `TOML11_USE_UNRELEASED_TOML_FEATURES`.
-//
 using lex_ml_basic_string_delim = repeat<lex_quotation_mark, exactly<3>>;
 using lex_ml_basic_string_open  = lex_ml_basic_string_delim;
 using lex_ml_basic_string_close = sequence<
@@ -196,18 +178,11 @@ using lex_ml_basic_string_close = sequence<
        maybe<lex_quotation_mark>, maybe<lex_quotation_mark>
    >;

-#ifdef TOML11_USE_UNRELEASED_TOML_FEATURES
 using lex_ml_basic_unescaped    = exclude<either<in_range<0x00, 0x08>, // 0x09
                                                 in_range<0x0a, 0x1F>, // is tab
                                                 character<0x5C>, // backslash
                                                 character<0x7F>, // DEL
                                                 lex_ml_basic_string_delim>>;
-#else // TOML v0.5.0
-using lex_ml_basic_unescaped    = exclude<either<in_range<0x00,0x1F>,
-                                                 character<0x5C>,
-                                                 character<0x7F>,
-                                                 lex_ml_basic_string_delim>>;
-#endif

 using lex_ml_basic_escaped_newline = sequence<
        lex_escape, maybe<lex_ws>, lex_newline,
--- a/toml/literal.hpp
+++ b/toml/literal.hpp
@@ -11,12 +11,9 @@ inline namespace literals
 inline namespace toml_literals
 {

-inline ::toml::value operator"" _toml(const char* str, std::size_t len)
+// implementation
+inline ::toml::value literal_internal_impl(::toml::detail::location loc)
 {
-    ::toml::detail::location<std::vector<char>>
-        loc(/* filename = */ std::string("TOML literal encoded in a C++ code"),
-            /* contents = */ std::vector<char>(str, str + len));
-
    // if there are some comments or empty lines, skip them.
    using skip_line = ::toml::detail::repeat<toml::detail::sequence<
            ::toml::detail::maybe<::toml::detail::lex_ws>,
@@ -76,11 +73,34 @@ inline ::toml::value operator"" _toml(const char* str, std::size_t len)
    }
    else // none of them.
    {
-        throw ::toml::syntax_error(data.unwrap_err(),
-                                   source_location(std::addressof(loc)));
+        throw ::toml::syntax_error(data.unwrap_err(), source_location(loc));
    }
+
 }

+inline ::toml::value operator"" _toml(const char* str, std::size_t len)
+{
+    ::toml::detail::location loc(
+            std::string("TOML literal encoded in a C++ code"),
+            std::vector<char>(str, str + len));
+    return literal_internal_impl(std::move(loc));
+}
+
+// value of __cplusplus in C++2a/20 mode is not fixed yet along compilers.
+// So here we use the feature test macro for `char8_t` itself.
+#if defined(__cpp_char8_t) && __cpp_char8_t >= 201811L
+// value of u8"" literal has been changed from char to char8_t and char8_t is
+// NOT compatible to char
+inline ::toml::value operator"" _toml(const char8_t* str, std::size_t len)
+{
+    ::toml::detail::location loc(
+            std::string("TOML literal encoded in a C++ code"),
+            std::vector<char>(reinterpret_cast<const char*>(str),
+                              reinterpret_cast<const char*>(str) + len));
+    return literal_internal_impl(std::move(loc));
+}
+#endif
+
 } // toml_literals
 } // literals
 } // toml
--- a/toml/parser.hpp
+++ b/toml/parser.hpp
--- a/toml/region.hpp
+++ b/toml/region.hpp
@@ -55,7 +55,7 @@ struct region_base
    // number of characters in the line after the region
    virtual std::size_t after()    const noexcept {return 0;}

-    virtual std::vector<std::string> comments()const {return {};}
+    virtual std::vector<std::string> comments() const {return {};}
    // ```toml
    // # comment_before
    // key = "value" # comment_inline
@@ -67,22 +67,21 @@ struct region_base
 //
 // it contains pointer to the file content and iterator that points the current
 // location.
-template<typename Container>
 struct location final : public region_base
 {
-    using const_iterator  = typename Container::const_iterator;
+    using const_iterator  = typename std::vector<char>::const_iterator;
    using difference_type = typename const_iterator::difference_type;
-    using source_ptr      = std::shared_ptr<const Container>;
+    using source_ptr      = std::shared_ptr<const std::vector<char>>;

-    static_assert(std::is_same<char, typename Container::value_type>::value,"");
-    static_assert(std::is_same<std::random_access_iterator_tag,
-        typename std::iterator_traits<const_iterator>::iterator_category>::value,
-        "container should be randomly accessible");
-
-    location(std::string name, Container cont)
-      : source_(std::make_shared<Container>(std::move(cont))), line_number_(1),
-        source_name_(std::move(name)), iter_(source_->cbegin())
+    location(std::string name, std::vector<char> cont)
+      : source_(std::make_shared<std::vector<char>>(std::move(cont))),
+        line_number_(1), source_name_(std::move(name)), iter_(source_->cbegin())
    {}
+    location(std::string name, const std::string& cont)
+      : source_(std::make_shared<std::vector<char>>(cont.begin(), cont.end())),
+        line_number_(1), source_name_(std::move(name)), iter_(source_->cbegin())
+    {}
+
    location(const location&) = default;
    location(location&&)      = default;
    location& operator=(const location&) = default;
@@ -195,33 +194,27 @@ struct location final : public region_base
 //
 // it contains pointer to the file content and iterator that points the first
 // and last location.
-template<typename Container>
 struct region final : public region_base
 {
-    using const_iterator = typename Container::const_iterator;
-    using source_ptr     = std::shared_ptr<const Container>;
-
-    static_assert(std::is_same<char, typename Container::value_type>::value,"");
-    static_assert(std::is_same<std::random_access_iterator_tag,
-        typename std::iterator_traits<const_iterator>::iterator_category>::value,
-        "container should be randomly accessible");
+    using const_iterator = typename std::vector<char>::const_iterator;
+    using source_ptr     = std::shared_ptr<const std::vector<char>>;

    // delete default constructor. source_ never be null.
    region() = delete;

-    region(const location<Container>& loc)
+    explicit region(const location& loc)
      : source_(loc.source()), source_name_(loc.name()),
        first_(loc.iter()), last_(loc.iter())
    {}
-    region(location<Container>&& loc)
+    explicit region(location&& loc)
      : source_(loc.source()), source_name_(loc.name()),
        first_(loc.iter()), last_(loc.iter())
    {}

-    region(const location<Container>& loc, const_iterator f, const_iterator l)
+    region(const location& loc, const_iterator f, const_iterator l)
      : source_(loc.source()), source_name_(loc.name()), first_(f), last_(l)
    {}
-    region(location<Container>&& loc, const_iterator f, const_iterator l)
+    region(location&& loc, const_iterator f, const_iterator l)
      : source_(loc.source()), source_name_(loc.name()), first_(f), last_(l)
    {}

@@ -419,107 +412,6 @@ struct region final : public region_base
    const_iterator first_, last_;
 };

-// to show a better error message.
-inline std::string format_underline(const std::string& message,
-        const std::vector<std::pair<region_base const*, std::string>>& reg_com,
-        const std::vector<std::string>& helps = {},
-        const bool colorize = TOML11_ERROR_MESSAGE_COLORIZED)
-{
-    assert(!reg_com.empty());
-
-    const auto line_num_width = static_cast<int>(std::max_element(
-        reg_com.begin(), reg_com.end(),
-        [](std::pair<region_base const*, std::string> const& lhs,
-           std::pair<region_base const*, std::string> const& rhs)
-        {
-            return lhs.first->line_num().size() < rhs.first->line_num().size();
-        }
-    )->first->line_num().size());
-
-    std::ostringstream retval;
-
-    if(colorize)
-    {
-        retval << color::colorize; // turn on ANSI color
-    }
-
-    // XXX
-    // Here, before `colorize` support, it does not output `[error]` prefix
-    // automatically. So some user may output it manually and this change may
-    // duplicate the prefix. To avoid it, check the first 7 characters and
-    // if it is "[error]", it removes that part from the message shown.
-    if(message.size() > 7 && message.substr(0, 7) == "[error]")
-    {
-        retval << color::bold << color::red << "[error]" << color::reset
-               << color::bold << message.substr(7) << color::reset << '\n';
-    }
-    else
-    {
-        retval << color::bold << color::red << "[error] " << color::reset
-               << color::bold << message << color::reset << '\n';
-    }
-
-    for(auto iter = reg_com.begin(); iter != reg_com.end(); ++iter)
-    {
-        // if the filenames are the same, print "..."
-        if(iter != reg_com.begin() &&
-           std::prev(iter)->first->name() == iter->first->name())
-        {
-            retval << color::bold << color::blue << "\n ...\n" << color::reset;
-        }
-        else // if filename differs, print " --> filename.toml"
-        {
-            if(iter != reg_com.begin()) {retval << '\n';}
-            retval << color::bold << color::blue << " --> " << color::reset
-                   << iter->first->name() << '\n';
-            // add one almost-empty line for readability
-            retval << make_string(static_cast<std::size_t>(line_num_width + 1), ' ')
-                   << color::bold << color::blue << " | "  << color::reset << '\n';
-        }
-        const region_base* const reg = iter->first;
-        const std::string&   comment = iter->second;
-
-        retval << ' ' << color::bold << color::blue << std::setw(line_num_width)
-               << std::right << reg->line_num() << " | "  << color::reset
-               << reg->line() << '\n';
-
-        retval << make_string(static_cast<std::size_t>(line_num_width + 1), ' ')
-               << color::bold << color::blue << " | " << color::reset
-               << make_string(reg->before(), ' ');
-
-        if(reg->size() == 1)
-        {
-            // invalid
-            // ^------
-            retval << color::bold << color::red
-                   << '^' << make_string(reg->after(), '-') << color::reset;
-        }
-        else
-        {
-            // invalid
-            // ~~~~~~~
-            const auto underline_len = std::min(reg->size(), reg->line().size());
-            retval << color::bold << color::red
-                   << make_string(underline_len, '~') << color::reset;
-        }
-        retval << ' ';
-        retval << comment;
-    }
-
-    if(!helps.empty())
-    {
-        retval << '\n';
-        retval << make_string(static_cast<std::size_t>(line_num_width + 1), ' ');
-        retval << color::bold << color::blue << " | " << color::reset;
-        for(const auto& help : helps)
-        {
-            retval << color::bold << "\nHint: " << color::reset;
-            retval << help;
-        }
-    }
-    return retval.str();
-}
-
 } // detail
 } // toml
 #endif// TOML11_REGION_H
--- a/toml/serializer.hpp
+++ b/toml/serializer.hpp
@@ -2,11 +2,13 @@
 // Distributed under the MIT License.
 #ifndef TOML11_SERIALIZER_HPP
 #define TOML11_SERIALIZER_HPP
-#include "value.hpp"
-#include "lexer.hpp"
-#include <limits>
 #include <cstdio>

+#include <limits>
+
+#include "lexer.hpp"
+#include "value.hpp"
+
 namespace toml
 {

@@ -22,39 +24,62 @@ namespace toml
 // Since toml restricts characters available in a bare key, generally a string
 // should be escaped. But checking whether a string needs to be surrounded by
 // a `"` and escaping some special character is boring.
-inline std::string format_key(const toml::key& key)
+template<typename charT, typename traits, typename Alloc>
+std::basic_string<charT, traits, Alloc>
+format_key(const std::basic_string<charT, traits, Alloc>& key)
 {
-    detail::location<toml::key> loc(key, key);
+    // check the key can be a bare (unquoted) key
+    detail::location loc(key, std::vector<char>(key.begin(), key.end()));
    detail::lex_unquoted_key::invoke(loc);
    if(loc.iter() == loc.end())
    {
        return key; // all the tokens are consumed. the key is unquoted-key.
    }
-    std::string token("\"");
+
+    //if it includes special characters, then format it in a "quoted" key.
+    std::basic_string<charT, traits, Alloc> serialized("\"");
    for(const char c : key)
    {
        switch(c)
        {
-            case '\\': {token += "\\\\"; break;}
-            case '\"': {token += "\\\""; break;}
-            case '\b': {token += "\\b";  break;}
-            case '\t': {token += "\\t";  break;}
-            case '\f': {token += "\\f";  break;}
-            case '\n': {token += "\\n";  break;}
-            case '\r': {token += "\\r";  break;}
-            default  : {token += c;      break;}
+            case '\\': {serialized += "\\\\"; break;}
+            case '\"': {serialized += "\\\""; break;}
+            case '\b': {serialized += "\\b";  break;}
+            case '\t': {serialized += "\\t";  break;}
+            case '\f': {serialized += "\\f";  break;}
+            case '\n': {serialized += "\\n";  break;}
+            case '\r': {serialized += "\\r";  break;}
+            default  : {serialized += c;      break;}
        }
    }
-    token += "\"";
-    return token;
+    serialized += "\"";
+    return serialized;
 }

-template<typename Comment,
-         template<typename ...> class Table,
-         template<typename ...> class Array>
+template<typename charT, typename traits, typename Alloc>
+std::basic_string<charT, traits, Alloc>
+format_keys(const std::vector<std::basic_string<charT, traits, Alloc>>& keys)
+{
+    std::basic_string<charT, traits, Alloc> serialized;
+    if(keys.empty()) {return serialized;}
+
+    for(const auto& ky : keys)
+    {
+        serialized += format_key(ky);
+        serialized += charT('.');
+    }
+    serialized.pop_back(); // remove the last dot '.'
+    return serialized;
+}
+
+template<typename Value>
 struct serializer
 {
-    using value_type           = basic_value<Comment, Table, Array>;
+    static_assert(detail::is_basic_value<Value>::value,
+                  "toml::serializer is for toml::value and its variants, "
+                  "toml::basic_value<...>.");
+
+    using value_type           = Value;
    using key_type             = typename value_type::key_type            ;
    using comment_type         = typename value_type::comment_type        ;
    using boolean_type         = typename value_type::boolean_type        ;
@@ -112,43 +137,8 @@ struct serializer
        {
            // the resulting value does not have any float specific part!
            token += ".0";
-            return token;
-        }
-        if(!has_exponent)
-        {
-            return token; // there is no exponent part. just return it.
-        }
-#ifdef TOML11_USE_UNRELEASED_TOML_FEATURES
-        // Although currently it is not released yet as a tagged version,
-        // TOML will allow zero-prefix in an exponent part, such as `1.234e+01`.
-        // ```toml
-        // num1 = 1.234e+1  # OK in TOML v0.5.0
-        // num2 = 1.234e+01 # error in TOML v0.5.0 but will be allowed soon
-        // ```
-        // To avoid `e+01`, the following `else` section removes the zero
-        // prefixes in the exponent part.
-        // If the feature is activated, it can be skipped.
-        return token;
-#else
-        // zero-prefix in an exponent is NOT allowed in TOML v0.5.0.
-        // remove it if it exists.
-        bool        sign_exists = false;
-        std::size_t zero_prefix = 0;
-        for(auto iter = std::next(e), iend = token.cend(); iter != iend; ++iter)
-        {
-            if(*iter == '+' || *iter == '-'){sign_exists = true; continue;}
-            if(*iter == '0'){zero_prefix += 1;}
-            else {break;}
-        }
-        if(zero_prefix != 0)
-        {
-            const auto offset = std::distance(token.cbegin(), e) +
-                               (sign_exists ? 2 : 1);
-            token.erase(static_cast<typename std::string::size_type>(offset),
-                        zero_prefix);
        }
        return token;
-#endif
    }
    std::string operator()(const string_type& s) const
    {
@@ -270,7 +260,7 @@ struct serializer
                std::string token;
                if(!keys_.empty())
                {
-                    token += this->serialize_key(keys_.back());
+                    token += format_key(keys_.back());
                    token += " = ";
                }
                bool failed = false;
@@ -326,7 +316,7 @@ struct serializer
                    }
                }
                token += "[[";
-                token += this->serialize_dotted_key(keys_);
+                token += format_keys(keys_);
                token += "]]\n";
                token += this->make_multiline_table(item.as_table());
            }
@@ -438,7 +428,7 @@ struct serializer
            std::string token;
            if(!this->keys_.empty())
            {
-                token += this->serialize_key(this->keys_.back());
+                token += format_key(this->keys_.back());
                token += " = ";
            }
            token += this->make_inline_table(v);
@@ -453,7 +443,7 @@ struct serializer
        if(!keys_.empty())
        {
            token += '[';
-            token += this->serialize_dotted_key(keys_);
+            token += format_keys(keys_);
            token += "]\n";
        }
        token += this->make_multiline_table(v);
@@ -462,25 +452,6 @@ struct serializer

  private:

-    std::string serialize_key(const toml::key& key) const
-    {
-        return ::toml::format_key(key);
-    }
-
-    std::string serialize_dotted_key(const std::vector<toml::key>& keys) const
-    {
-        std::string token;
-        if(keys.empty()){return token;}
-
-        for(const auto& k : keys)
-        {
-            token += this->serialize_key(k);
-            token += '.';
-        }
-        token.erase(token.size() - 1, 1); // remove trailing `.`
-        return token;
-    }
-
    std::string escape_basic_string(const std::string& s) const
    {
        //XXX assuming `s` is a valid utf-8 sequence.
@@ -586,7 +557,7 @@ struct serializer
        for(const auto& item : v)
        {
            if(is_first) {is_first = false;} else {token += ',';}
-            token += visit(serializer(std::numeric_limits<std::size_t>::max(),
+            token += visit(serializer((std::numeric_limits<std::size_t>::max)(),
                                      this->float_prec_, true), item);
        }
        token += ']';
@@ -604,9 +575,9 @@ struct serializer
        {
            // in inline tables, trailing comma is not allowed (toml-lang #569).
            if(is_first) {is_first = false;} else {token += ',';}
-            token += this->serialize_key(kv.first);
+            token += format_key(kv.first);
            token += '=';
-            token += visit(serializer(std::numeric_limits<std::size_t>::max(),
+            token += visit(serializer((std::numeric_limits<std::size_t>::max)(),
                                      this->float_prec_, true), kv.second);
        }
        token += '}';
@@ -635,7 +606,7 @@ struct serializer
                    token += '\n';
                }
            }
-            const auto key_and_sep    = this->serialize_key(kv.first) + " = ";
+            const auto key_and_sep    = format_key(kv.first) + " = ";
            const auto residual_width = (this->width_ > key_and_sep.size()) ?
                                        this->width_ - key_and_sep.size() : 0;
            token += key_and_sep;
@@ -717,6 +688,7 @@ format(const basic_value<C, M, V>& v, std::size_t w = 80u,
       int fprec = std::numeric_limits<toml::floating>::max_digits10,
       bool no_comment = false, bool force_inline = false)
 {
+    using value_type = basic_value<C, M, V>;
    // if value is a table, it is considered to be a root object.
    // the root object can't be an inline table.
    if(v.is_table())
@@ -727,10 +699,11 @@ format(const basic_value<C, M, V>& v, std::size_t w = 80u,
            oss << v.comments();
            oss << '\n'; // to split the file comment from the first element
        }
-        oss << visit(serializer<C, M, V>(w, fprec, no_comment, false), v);
+        const auto serialized = visit(serializer<value_type>(w, fprec, no_comment, false), v);
+        oss << serialized;
        return oss.str();
    }
-    return visit(serializer<C, M, V>(w, fprec, force_inline), v);
+    return visit(serializer<value_type>(w, fprec, force_inline), v);
 }

 namespace detail
@@ -766,6 +739,8 @@ template<typename charT, typename traits, typename C,
 std::basic_ostream<charT, traits>&
 operator<<(std::basic_ostream<charT, traits>& os, const basic_value<C, M, V>& v)
 {
+    using value_type = basic_value<C, M, V>;
+
    // get status of std::setw().
    const auto w     = static_cast<std::size_t>(os.width());
    const int  fprec = static_cast<int>(os.precision());
@@ -781,7 +756,8 @@ operator<<(std::basic_ostream<charT, traits>& os, const basic_value<C, M, V>& v)
        os << '\n'; // to split the file comment from the first element
    }
    // the root object can't be an inline table. so pass `false`.
-    os << visit(serializer<C, M, V>(w, fprec, false, no_comment), v);
+    const auto serialized = visit(serializer<value_type>(w, fprec, no_comment, false), v);
+    os << serialized;

    // if v is a non-table value, and has only one comment, then
    // put a comment just after a value. in the following way.
--- a/toml/source_location.hpp
+++ b/toml/source_location.hpp
@@ -2,9 +2,10 @@
 // Distributed under the MIT License.
 #ifndef TOML11_SOURCE_LOCATION_HPP
 #define TOML11_SOURCE_LOCATION_HPP
-#include "region.hpp"
 #include <cstdint>

+#include "region.hpp"
+
 namespace toml
 {

@@ -38,12 +39,12 @@ struct source_location
  public:

    source_location()
-        : line_num_(0), column_num_(0), region_size_(0),
+        : line_num_(1), column_num_(1), region_size_(1),
          file_name_("unknown file"), line_str_("")
    {}

    explicit source_location(const detail::region_base* reg)
-        : line_num_(0), column_num_(0), region_size_(0),
+        : line_num_(1), column_num_(1), region_size_(1),
          file_name_("unknown file"), line_str_("")
    {
        if(reg)
@@ -60,6 +61,21 @@ struct source_location
        }
    }

+    explicit source_location(const detail::region& reg)
+        : line_num_(static_cast<std::uint_least32_t>(std::stoul(reg.line_num()))),
+          column_num_(static_cast<std::uint_least32_t>(reg.before() + 1)),
+          region_size_(static_cast<std::uint_least32_t>(reg.size())),
+          file_name_(reg.name()),
+          line_str_ (reg.line())
+    {}
+    explicit source_location(const detail::location& loc)
+        : line_num_(static_cast<std::uint_least32_t>(std::stoul(loc.line_num()))),
+          column_num_(static_cast<std::uint_least32_t>(loc.before() + 1)),
+          region_size_(static_cast<std::uint_least32_t>(loc.size())),
+          file_name_(loc.name()),
+          line_str_ (loc.line())
+    {}
+
    ~source_location() = default;
    source_location(source_location const&) = default;
    source_location(source_location &&)     = default;
@@ -82,5 +98,135 @@ struct source_location
    std::string         line_str_;
 };

+namespace detail
+{
+
+// internal error message generation.
+inline std::string format_underline(const std::string& message,
+        const std::vector<std::pair<source_location, std::string>>& loc_com,
+        const std::vector<std::string>& helps = {},
+        const bool colorize = TOML11_ERROR_MESSAGE_COLORIZED)
+{
+    std::size_t line_num_width = 0;
+    for(const auto& lc : loc_com)
+    {
+        std::uint_least32_t line = lc.first.line();
+        std::size_t        digit = 0;
+        while(line != 0)
+        {
+            line  /= 10;
+            digit +=  1;
+        }
+        line_num_width = (std::max)(line_num_width, digit);
+    }
+    // 1 is the minimum width
+    line_num_width = std::max<std::size_t>(line_num_width, 1);
+
+    std::ostringstream retval;
+
+    if(colorize)
+    {
+        retval << color::colorize; // turn on ANSI color
+    }
+
+    // XXX
+    // Here, before `colorize` support, it does not output `[error]` prefix
+    // automatically. So some user may output it manually and this change may
+    // duplicate the prefix. To avoid it, check the first 7 characters and
+    // if it is "[error]", it removes that part from the message shown.
+    if(message.size() > 7 && message.substr(0, 7) == "[error]")
+    {
+        retval << color::bold << color::red << "[error]" << color::reset
+               << color::bold << message.substr(7) << color::reset << '\n';
+    }
+    else
+    {
+        retval << color::bold << color::red << "[error] " << color::reset
+               << color::bold << message << color::reset << '\n';
+    }
+
+    const auto format_one_location = [line_num_width]
+        (std::ostringstream& oss,
+         const source_location& loc, const std::string& comment) -> void
+        {
+            oss << ' ' << color::bold << color::blue
+                << std::setw(static_cast<int>(line_num_width))
+                << std::right << loc.line() << " | "  << color::reset
+                << loc.line_str() << '\n';
+
+            oss << make_string(line_num_width + 1, ' ')
+                << color::bold << color::blue << " | " << color::reset
+                << make_string(loc.column()-1 /*1-origin*/, ' ');
+
+            if(loc.region() == 1)
+            {
+                // invalid
+                // ^------
+                oss << color::bold << color::red << "^---" << color::reset;
+            }
+            else
+            {
+                // invalid
+                // ~~~~~~~
+                const auto underline_len = (std::min)(
+                    static_cast<std::size_t>(loc.region()), loc.line_str().size());
+                oss << color::bold << color::red
+                    << make_string(underline_len, '~') << color::reset;
+            }
+            oss << ' ';
+            oss << comment;
+            return;
+        };
+
+    assert(!loc_com.empty());
+
+    // --> example.toml
+    //   |
+    retval << color::bold << color::blue << " --> " << color::reset
+           << loc_com.front().first.file_name() << '\n';
+    retval << make_string(line_num_width + 1, ' ')
+           << color::bold << color::blue << " |\n"  << color::reset;
+    // 1 | key value
+    //   |    ^--- missing =
+    format_one_location(retval, loc_com.front().first, loc_com.front().second);
+
+    // process the rest of the locations
+    for(std::size_t i=1; i<loc_com.size(); ++i)
+    {
+        const auto& prev = loc_com.at(i-1);
+        const auto& curr = loc_com.at(i);
+
+        retval << '\n';
+        // if the filenames are the same, print "..."
+        if(prev.first.file_name() == curr.first.file_name())
+        {
+            retval << color::bold << color::blue << " ...\n" << color::reset;
+        }
+        else // if filename differs, print " --> filename.toml" again
+        {
+            retval << color::bold << color::blue << " --> " << color::reset
+                   << curr.first.file_name() << '\n';
+            retval << make_string(line_num_width + 1, ' ')
+                   << color::bold << color::blue << " |\n"  << color::reset;
+        }
+
+        format_one_location(retval, curr.first, curr.second);
+    }
+
+    if(!helps.empty())
+    {
+        retval << '\n';
+        retval << make_string(line_num_width + 1, ' ');
+        retval << color::bold << color::blue << " |" << color::reset;
+        for(const auto& help : helps)
+        {
+            retval << color::bold << "\nHint: " << color::reset;
+            retval << help;
+        }
+    }
+    return retval.str();
+}
+
+} // detail
 } // toml
 #endif// TOML11_SOURCE_LOCATION_HPP
--- a/toml/string.hpp
+++ b/toml/string.hpp
@@ -2,9 +2,11 @@
 // Distributed under the MIT License.
 #ifndef TOML11_STRING_HPP
 #define TOML11_STRING_HPP
+#include <cstdint>
+
 #include <algorithm>
 #include <string>
-#include <cstdint>
+
 #if __cplusplus >= 201703L
 #if __has_include(<string_view>)
 #include <string_view>
--- a/toml/traits.hpp
+++ b/toml/traits.hpp
@@ -2,11 +2,13 @@
 // Distributed under the MIT License.
 #ifndef TOML11_TRAITS_HPP
 #define TOML11_TRAITS_HPP
+#include <chrono>
+#include <forward_list>
+#include <string>
+#include <tuple>
 #include <type_traits>
 #include <utility>
-#include <chrono>
-#include <tuple>
-#include <string>
+
 #if __cplusplus >= 201703L
 #if __has_include(<string_view>)
 #include <string_view>
@@ -43,17 +45,23 @@ struct has_mapped_type_impl
    template<typename T> static std::true_type  check(typename T::mapped_type*);
    template<typename T> static std::false_type check(...);
 };
-struct has_resize_method_impl
+struct has_reserve_method_impl
 {
-    constexpr static std::size_t dummy=0;
-    template<typename T> static std::true_type  check(decltype(std::declval<T>().resize(dummy))*);
    template<typename T> static std::false_type check(...);
+    template<typename T> static std::true_type  check(
+        decltype(std::declval<T>().reserve(std::declval<std::size_t>()))*);
+};
+struct has_push_back_method_impl
+{
+    template<typename T> static std::false_type check(...);
+    template<typename T> static std::true_type  check(
+        decltype(std::declval<T>().push_back(std::declval<typename T::value_type>()))*);
 };
-
 struct is_comparable_impl
 {
-    template<typename T> static std::true_type  check(decltype(std::declval<T>() < std::declval<T>())*);
    template<typename T> static std::false_type check(...);
+    template<typename T> static std::true_type  check(
+        decltype(std::declval<T>() < std::declval<T>())*);
 };

 struct has_from_toml_method_impl
@@ -91,7 +99,9 @@ struct has_key_type    : decltype(has_key_type_impl::check<T>(nullptr)){};
 template<typename T>
 struct has_mapped_type : decltype(has_mapped_type_impl::check<T>(nullptr)){};
 template<typename T>
-struct has_resize_method : decltype(has_resize_method_impl::check<T>(nullptr)){};
+struct has_reserve_method : decltype(has_reserve_method_impl::check<T>(nullptr)){};
+template<typename T>
+struct has_push_back_method : decltype(has_push_back_method_impl::check<T>(nullptr)){};
 template<typename T>
 struct is_comparable : decltype(is_comparable_impl::check<T>(nullptr)){};

@@ -149,6 +159,10 @@ template<typename T> struct is_std_tuple : std::false_type{};
 template<typename ... Ts>
 struct is_std_tuple<std::tuple<Ts...>> : std::true_type{};

+template<typename T> struct is_std_forward_list : std::false_type{};
+template<typename T>
+struct is_std_forward_list<std::forward_list<T>> : std::true_type{};
+
 template<typename T> struct is_chrono_duration: std::false_type{};
 template<typename Rep, typename Period>
 struct is_chrono_duration<std::chrono::duration<Rep, Period>>: std::true_type{};
--- a/toml/types.hpp
+++ b/toml/types.hpp
@@ -2,12 +2,13 @@
 // Distributed under the MIT License.
 #ifndef TOML11_TYPES_HPP
 #define TOML11_TYPES_HPP
+#include <unordered_map>
+#include <vector>
+
+#include "comments.hpp"
 #include "datetime.hpp"
 #include "string.hpp"
 #include "traits.hpp"
-#include "comments.hpp"
-#include <vector>
-#include <unordered_map>

 namespace toml
 {
--- a/toml/utility.hpp
+++ b/toml/utility.hpp
@@ -2,10 +2,11 @@
 // Distributed under the MIT License.
 #ifndef TOML11_UTILITY_HPP
 #define TOML11_UTILITY_HPP
-#include "traits.hpp"
-#include <utility>
 #include <memory>
 #include <sstream>
+#include <utility>
+
+#include "traits.hpp"

 #if __cplusplus >= 201402L
 #  define TOML11_MARK_AS_DEPRECATED(msg) [[deprecated(msg)]]
@@ -36,30 +37,25 @@ inline std::unique_ptr<T> make_unique(Ts&& ... args)

 namespace detail
 {
-
-template<typename T>
-inline void resize_impl(T& container, std::size_t N, std::true_type)
+template<typename Container>
+void try_reserve_impl(Container& container, std::size_t N, std::true_type)
 {
-    container.resize(N);
-    return ;
+    container.reserve(N);
+    return;
 }
-
-template<typename T>
-inline void resize_impl(T& container, std::size_t N, std::false_type)
+template<typename Container>
+void try_reserve_impl(Container&, std::size_t, std::false_type) noexcept
 {
-    if(container.size() >= N) {return;}
-
-    throw std::invalid_argument("not resizable type");
+    return;
 }
-
 } // detail

-template<typename T>
-inline void resize(T& container, std::size_t N)
+template<typename Container>
+void try_reserve(Container& container, std::size_t N)
 {
-    if(container.size() == N) {return;}
-
-    return detail::resize_impl(container, N, detail::has_resize_method<T>());
+    if(N <= container.size()) {return;}
+    detail::try_reserve_impl(container, N, detail::has_reserve_method<Container>{});
+    return;
 }

 namespace detail
--- a/toml/value.hpp
+++ b/toml/value.hpp
Author	SHA1	Message	Date
ToruNiina	c037913b2c	doc: update link to the TOML spec	2020-09-20 19:24:48 +09:00
ToruNiina	6a328fe890	doc: recommend to set /Zc:__cplusplus	2020-09-20 18:07:58 +09:00
ToruNiina	7c18cbb1d9	doc: update section "contributors"	2020-09-19 20:35:37 +09:00
ToruNiina	ba7d49f452	test: use normal string literal as a workaround for older version of gcc	2020-09-19 19:08:20 +09:00
ToruNiina	b0784ce286	test: in case of comment-before-comma	2020-09-19 18:24:23 +09:00
ToruNiina	670186fac7	Merge branch 'master' into allow-comment-before-comma	2020-09-19 18:10:45 +09:00
ToruNiina	5005998709	Merge branch 'master' into cpp20-mode-u8literal-workaround	2020-09-19 13:42:12 +09:00
ToruNiina	84fb703e04	ci: add utf-8 option to MSVC	2020-09-19 00:41:05 +09:00
ToruNiina	8c2560761b	chore: enable to use __cplusplus on MSVC related: https://github.com/ToruNiina/toml11/issues/112	2020-09-19 00:40:44 +09:00
ToruNiina	07ea5e52e2	ci: pass REQ_FS_LIB=ON in case of g++-8 & C++20	2020-09-16 22:16:20 +09:00
ToruNiina	d2b1e962c9	ci: add std=20 to some compilers on github actions	2020-09-16 21:28:19 +09:00
ToruNiina	528031012d	test: add test for u8""_toml literals	2020-09-16 21:25:38 +09:00
ToruNiina	c205c762fe	test: remove needless `u8`s from ascii characters	2020-09-16 21:25:04 +09:00
ToruNiina	a32cd6cb61	feat: enable to use u8""_toml literal in C++20	2020-09-16 21:24:03 +09:00
ToruNiina	38e113d2dc	ci: set BUILD_TEST=ON on appveyor	2020-09-15 22:40:24 +09:00
Toru Niina	f15480ae4d	Merge pull request #130 from MoAlyousef/master Make toml11_BUILD_TEST Off by default	2020-09-15 22:28:34 +09:00
MoAlyousef	00bec8ae45	update Running Tests heading	2020-09-14 22:05:15 +03:00
MoAlyousef	d599edd1d4	make testing optional	2020-09-14 20:34:19 +03:00
MoAlyousef	a9534579c6	make testing optional	2020-09-14 20:25:38 +03:00
ToruNiina	c8ff302c94	test: add test for no-eof-newline cases	2020-09-14 16:39:05 +09:00
ToruNiina	003bc16c1b	fix: skip the last zero in the file	2020-09-14 16:35:51 +09:00
Toru Niina	9132abc5c4	Merge pull request #127 from kenichiice/fix-include Fix include path in README	2020-09-07 16:19:29 +09:00
OGAWA KenIchi	99d565bcc4	doc: fix include path * see #72	2020-09-07 15:32:28 +09:00
ToruNiina	5f38127692	feat: allow comments before comma replace ws by ws_comment_newline, as suggested. discussed here: toml-lang/toml/issues/766	2020-08-16 11:03:58 +09:00
ToruNiina	3c3ebd88b4	feat: improve error message about invalid keys	2020-08-09 18:38:50 +09:00
ToruNiina	08f7ea9c56	refactor: remove extraneous whitespaces in errmsg	2020-08-09 18:38:21 +09:00
ToruNiina	cde29399f4	fix: use 1 in source_location as the default pos	2020-08-07 22:24:01 +09:00
ToruNiina	eec429e31b	ci: add REQUIRE_FILESYSTEM_LIBRARY on CI	2020-08-06 16:35:49 +09:00
ToruNiina	79ddcaece6	chore: add CMake option to link with (std)c++fs	2020-08-06 16:29:24 +09:00
ToruNiina	8398b9a08b	test: use array for char* forgot to delete	2020-08-05 20:43:48 +09:00
ToruNiina	9c5abf0bfd	test: check each overload compiles	2020-08-05 20:29:07 +09:00
ToruNiina	4fa94d45b3	fix: use const char* instead of &char[N] to enable to pass char*, not only string literal	2020-08-04 20:08:58 +09:00
ToruNiina	46e84a9cc2	refactor: Merge branch 'refactor-region'	2020-07-31 12:45:52 +09:00
ToruNiina	4e6ae9a994	refactor: avoid string construct in format_ul	2020-07-30 16:11:35 +09:00
ToruNiina	f23c003d2f	fix: add missing namespace specifier	2020-07-28 00:04:25 +09:00
ToruNiina	4b719f0806	refactor: use location() instead of get_region	2020-07-27 23:15:14 +09:00
ToruNiina	22ace027de	refactor: rm template from detail::change_region	2020-07-27 23:04:24 +09:00
ToruNiina	bc219af5b5	refactor: use location() member instead of ctor	2020-07-27 23:03:33 +09:00
ToruNiina	68e8a31659	refactor: remove needless addressof() call	2020-07-27 23:00:40 +09:00
ToruNiina	32a5341d09	refactor: use source_location, not region_base*	2020-07-27 22:29:18 +09:00
ToruNiina	ce68f6f4c2	refactor: check (always-valid) ptr before deref	2020-07-27 21:32:35 +09:00
ToruNiina	e696aabd11	refactor: change internal interface to reduce code to remove `std::addressof` calls, get_region(toml::value) now returns a pointer to region.	2020-07-27 00:48:04 +09:00
ToruNiina	7fb93e2f54	fix: add missing `explicit` to detail::region	2020-07-27 00:20:26 +09:00
ToruNiina	19cc9a2edf	refactor: remove template from detail::region	2020-07-25 22:01:34 +09:00
ToruNiina	72f5afb6af	refactor: remove template from detail::location	2020-07-25 21:06:26 +09:00
ToruNiina	a8fa14d159	refactor: remove vec() method, use a constructor	2020-07-21 20:55:18 +09:00
ToruNiina	75999aa9ad	refactor: add a constructor to location By adding the constructor, vec() would not be not needed. But inserting Container = std::string makes the constructor ambiguous, so it breaks the current code.	2020-07-21 20:53:44 +09:00
ToruNiina	259da54edb	refactor: always use vector<char> in location `location` and `region` have a (shared_ptr to the) container of TOML contents. Those take a template argument to allow both std::vector<char> and std::string as an interanal container. But since those are internal feature, i.e. it should not be used by a user directly, this template can be removed by re-writing a parser a bit. This introduces a complexity to toml11 error reporting system, so I'm removing this. First, remove all the location<std::string> from the parser. Then the template argument can be removed because everyone uses std::vector<char> now.	2020-07-20 19:52:11 +09:00
ToruNiina	b461f363da	refactor: add a method to reduce complexity later	2020-07-20 19:40:55 +09:00
ToruNiina	d43139a471	doc: update Contributors section	2020-07-19 19:50:02 +09:00
ToruNiina	a344668fa2	doc: update version to 3.5.0	2020-07-19 19:12:18 +09:00
ToruNiina	25aa97a435	doc: add actions status badge to README	2020-07-19 19:09:47 +09:00
ToruNiina	af70d3dfed	ci [skip ci]: add github actions workflow file	2020-07-19 17:13:39 +09:00
ToruNiina	8b5cfb4105	test: add missing `binary` flag to ifstream	2020-07-19 16:57:20 +09:00
ToruNiina	4e0624aa60	feat: make sure the last null is removed	2020-07-19 16:56:31 +09:00
ToruNiina	3ac2c065eb	Merge branch 'reorder-headers' to master	2020-07-17 15:17:40 +09:00
ToruNiina	470f81dc94	fix: #123 merge branch 'windows-nominmax'	2020-07-10 20:55:53 +09:00
ToruNiina	93a9f2711c	test: add windows.h test	2020-07-10 18:32:59 +09:00
ToruNiina	761e576991	fix: workaround for windows.h that defines min/max related to #123	2020-07-10 15:07:13 +09:00
ToruNiina	e6e84714c5	Merge branch 'master' into reorder-headers	2020-07-10 00:06:22 +09:00
Toru Niina	1efc99e11c	Merge pull request #121 from SeverinLeonhardt/fix_msvc_c4866 Fix MSVC warning C4866	2020-07-03 21:37:22 +09:00
Marius Maaß	92aa42a58e	Fix MSVC warning C4866 This fixes the warning "compiler may not enforce left-to-right evaluation order for call to" that is caused by Visual Studio if this is compiled with a target of C++17.	2020-07-03 08:00:47 +02:00
ToruNiina	b1c9df8998	feat: reorder headers following google c++ style related to: #115	2020-06-28 00:58:20 +09:00
ToruNiina	9633e5fe5a	doc: add iteration examples into as_xxx section related to #120	2020-06-21 14:11:26 +09:00
ToruNiina	2164fd39f7	doc: explain about the type of the top-level value fix #120.	2020-06-21 14:04:20 +09:00
ToruNiina	c22a3fd227	feat: support parse(std::filesystem::path) #113	2020-06-07 15:11:48 +09:00
ToruNiina	57c6652360	Merge branch 'master' into std-filesystem	2020-06-06 17:25:26 +09:00
ToruNiina	defde33544	fix: avoid ambiguity in overload resolution Since both `std::string` and `std::filesystem::path` can be convertible from `const char &[N]` (like, `parse("file.toml")`), after adding `parse(std::filesystem::path)`, the overload resolution of `parse("file.toml")` becomes ambiguous. By adding `parse(...)` that exactly matches to `parse("file.toml")`, we can remove this ambiguity.	2020-06-06 17:18:02 +09:00
ToruNiina	46ed051740	fix: pass path.string as a filename	2020-06-05 23:15:19 +09:00
ToruNiina	2963d9a25b	feat: add std::filesystem::path support	2020-06-05 19:43:23 +09:00
Toru Niina	531f335417	Merge pull request #119 from halfelf/fix/readme_finding_value_in_table fix: "Finding a value in an array" example in README	2020-05-20 00:27:33 +09:00
Shu Wang	f29f42277e	fix: "Finding a value in an array" example in README	2020-05-18 13:53:48 +08:00
Toru Niina	b03cde566a	Merge pull request #117 from usefulcat/master when parsing a local_time, parse up to 9 digits worth (nanoseconds) o…	2020-05-11 13:36:23 +09:00
Scott McCaskill	57d4e196a3	when parsing a local_time, parse up to 9 digits worth (nanoseconds) of fractional seconds	2020-05-10 16:06:52 -05:00
ToruNiina	deb3ab6617	ci: add DISALLOW_HETEROGENEOUS_ARRAYS	2020-04-03 23:57:52 +09:00
ToruNiina	bf992e8f94	doc: update README for v1-rc1	2020-04-03 23:45:45 +09:00
ToruNiina	7c07f4382c	ci: add DISALLOW_HETEROGENEOUS_ARRAYS to toml-test	2020-04-03 23:43:59 +09:00
ToruNiina	125f608fa5	feat: remove TOML11_UNRELEASED_FEATURES. v1.0.0-rc.1 has been released	2020-04-03 23:42:58 +09:00
ToruNiina	4d0ed847f9	test: remove default ctor from test code	2020-03-30 15:04:51 +09:00
ToruNiina	79594709fe	fix: don't use default ctor when converting to map	2020-03-30 15:02:26 +09:00
ToruNiina	55a738c11f	Merge branch 'do-not-require-default-ctor-108' fix #108.	2020-03-28 23:19:52 +09:00
ToruNiina	eebe1f87e6	fix: update cmake version 3.4.0	2020-03-28 17:59:10 +09:00
ToruNiina	95c3b5f538	feat: use push_back instead of resize	2020-03-27 18:06:26 +09:00
ToruNiina	e2790c9e7b	test: remove test_resize and add test_try_reserve	2020-03-27 18:06:02 +09:00
ToruNiina	9b52dc0131	feat: remove resize and add try_reserve	2020-03-27 18:05:31 +09:00
ToruNiina	5212992f05	feat: add is_std_forward_list std::forward_list does not have push_back, insert, or emplace but push_front, insert_after, and emplace_after. We need to distinguish it from other continers.	2020-03-27 18:02:37 +09:00
ToruNiina	fcd6e47500	feat: add meta funcs, has_reserve/push_back_method	2020-03-27 18:01:47 +09:00
ToruNiina	31826b55ce	feat: avoid double checking in helper methods	2020-03-25 22:49:19 +09:00
ToruNiina	e3fc354e8d	Merge branch 'shorten-switch-cast'	2020-03-24 22:43:09 +09:00
ToruNiina	ea87f92358	doc: update exception section in README (fix #107 )	2020-03-23 20:57:36 +09:00
ToruNiina	c259456282	ci: fix Travis.CI OS X build	2020-03-22 20:40:02 +09:00
ToruNiina	d7662347f2	refactor: shorten switch_cast definition by macro	2020-03-21 17:44:23 +09:00
ToruNiina	5f5539d402	feat: throw informative error from value.at(...)	2020-03-21 17:09:04 +09:00
ToruNiina	c2151cab0b	refactor: show func name in bad_cast from helpers	2020-03-21 17:06:34 +09:00
ToruNiina	653c87592c	feat: enable to show function name in bad_cast	2020-03-21 17:04:05 +09:00
ToruNiina	bdf4e75122	refactor: move helper function from get to value	2020-03-21 16:57:12 +09:00
ToruNiina	60d23116ba	Merge branch 'master' of github.com:ToruNiina/toml11	2020-03-13 14:38:33 +09:00
ToruNiina	af8cf9ddc5	refactor: remove redundant functions in serializer	2020-03-13 13:55:14 +09:00
ToruNiina	f125cca010	refactor: simplify serializer's template argument	2020-03-12 13:46:17 +09:00
ToruNiina	a20a2c0b80	doc: update README	2020-03-01 00:35:27 +09:00
ToruNiina	9694afbe32	Merge branch 'improve-error-message'	2020-02-29 23:43:23 +09:00
ToruNiina	d11e42ca7e	fix: explicitly say the table is top-level The top-level table has its region at the first character of the file. That means that, in the case when a key is not found in the top-level table, the error message points to the first character. If the file has its first table at the first line, the error message would be like this. ```console [error] key "a" not found --> example.toml \| 1 \| [table] \| ^------ in this table ``` It actually points to the top-level table at the first character, not `[table]`. But it is too confusing. To avoid the confusion, the error message should explicitly say "key not found in the top-level table".	2020-02-29 22:56:29 +09:00
ToruNiina	128b66bda9	refactor: add missing whitespace	2020-02-29 22:54:50 +09:00
ToruNiina	d1af42f151	refactor: add throw_key_not_found_error and replace related throw statements with it	2020-02-29 22:23:15 +09:00
ToruNiina	8acf105b56	doc: update contributor list and test commands	2020-02-27 19:30:34 +09:00
Toru Niina	b86b5364ba	Merge pull request #103 from jwillikers/fix_tests Use FetchContent to retrieve TOML test data	2020-02-27 19:13:02 +09:00
Jordan Williams	bfe57340f4	no longer explicitly clone the TOML repository in CI builds	2020-02-24 08:03:29 -06:00
Jordan Williams	02a6f029ad	use ExternalProject to download the toml tests In order to evaluate the relative paths correctly, add_test should use the current binary directory as the working directory.	2020-02-24 07:59:59 -06:00
Jordan Williams	9017900ff3	set version directly from CMake project command This silences the warning for CMake policy CMP0048: https://cmake.org/cmake/help/v3.0/policy/CMP0048.html	2020-02-24 07:35:59 -06:00
Jordan Williams	3c5ebd73d7	require CMake version 3.1	2020-02-24 07:31:48 -06:00
Jordan Williams	2223eb4f62	Revert "no longer explicitly clone the TOML repository in CI builds" This reverts commit `fe644ea4b7`.	2020-02-24 07:31:15 -06:00
Jordan Williams	a655a71cef	Revert "use FetchContent to retrieve TOML test data" This reverts commit `4c34986db0`.	2020-02-24 07:31:06 -06:00
ToruNiina	c34001725c	Merge branch 'workaround-gcc-48x'	2020-02-20 11:59:49 +09:00
ToruNiina	5e3ffb70dd	fix: check clang macro when checking gcc is used	2020-02-19 17:00:22 +09:00
ToruNiina	2265ca41c6	ci: test with gcc 4.8 and 4.9 on CI	2020-02-19 15:47:34 +09:00
ToruNiina	82fec38e37	refactor: simplify internally-used function	2020-02-19 15:46:25 +09:00
ToruNiina	189b910384	fix: solve #97 in the naivest way, macros	2020-02-19 15:44:38 +09:00
Jordan Williams	fe644ea4b7	no longer explicitly clone the TOML repository in CI builds	2020-02-18 20:21:02 -06:00
Jordan Williams	4c34986db0	use FetchContent to retrieve TOML test data	2020-02-18 19:37:28 -06:00