Merge branch 'develop'

But I do not know if they copile with QuickBook.

.drone.star

@@ -0,0 +1,36 @@
+# Use, modification, and distribution are
+# subject to the Boost Software License, Version 1.0. (See accompanying
+# file LICENSE.txt)
+#
+# Copyright Rene Rivera 2020.
+
+# For Drone CI we use the Starlark scripting language to reduce duplication.
+# As the yaml syntax for Drone CI is rather limited.
+#
+#
+globalenv={}
+linuxglobalimage="cppalliance/droneubuntu1604:1"
+windowsglobalimage="cppalliance/dronevs2019"
+
+def main(ctx):
+  return [
+  linux_cxx("TOOLSET=gcc COMPILER=g++ CXXSTD=03,11 Job 0", "g++", packages="", buildtype="boost", buildscript="drone", image=linuxglobalimage, environment={'TOOLSET': 'gcc', 'COMPILER': 'g++', 'CXXSTD': '03,11', 'DRONE_JOB_UUID': 'b6589fc6ab'}, globalenv=globalenv),
+  linux_cxx("TOOLSET=gcc COMPILER=g++-4.7 CXXSTD=03,11 Job 1", "g++-4.7", packages="g++-4.7", buildtype="boost", buildscript="drone", image=linuxglobalimage, environment={'TOOLSET': 'gcc', 'COMPILER': 'g++-4.7', 'CXXSTD': '03,11', 'DRONE_JOB_UUID': '356a192b79'}, globalenv=globalenv),
+  linux_cxx("TOOLSET=gcc COMPILER=g++-4.8 CXXSTD=03,11 Job 2", "g++-4.8", packages="g++-4.8", buildtype="boost", buildscript="drone", image=linuxglobalimage, environment={'TOOLSET': 'gcc', 'COMPILER': 'g++-4.8', 'CXXSTD': '03,11', 'DRONE_JOB_UUID': 'da4b9237ba'}, globalenv=globalenv),
+  linux_cxx("TOOLSET=gcc COMPILER=g++-4.9 CXXSTD=03,11 Job 3", "g++-4.9", packages="g++-4.9", buildtype="boost", buildscript="drone", image=linuxglobalimage, environment={'TOOLSET': 'gcc', 'COMPILER': 'g++-4.9', 'CXXSTD': '03,11', 'DRONE_JOB_UUID': '77de68daec'}, globalenv=globalenv),
+  linux_cxx("TOOLSET=gcc COMPILER=g++-5 CXXSTD=03,11,14,1z Job 4", "g++-5", packages="g++-5", buildtype="boost", buildscript="drone", image=linuxglobalimage, environment={'TOOLSET': 'gcc', 'COMPILER': 'g++-5', 'CXXSTD': '03,11,14,1z', 'DRONE_JOB_UUID': '1b64538924'}, globalenv=globalenv),
+  linux_cxx("TOOLSET=gcc COMPILER=g++-6 CXXSTD=03,11,14,1z Job 5", "g++-6", packages="g++-6", buildtype="boost", buildscript="drone", image=linuxglobalimage, environment={'TOOLSET': 'gcc', 'COMPILER': 'g++-6', 'CXXSTD': '03,11,14,1z', 'DRONE_JOB_UUID': 'ac3478d69a'}, globalenv=globalenv),
+  linux_cxx("TOOLSET=gcc COMPILER=g++-7 CXXSTD=03,11,14,17 Job 6", "g++-7", packages="g++-7", buildtype="boost", buildscript="drone", image="cppalliance/droneubuntu1404:1", environment={'TOOLSET': 'gcc', 'COMPILER': 'g++-7', 'CXXSTD': '03,11,14,17', 'DRONE_JOB_UUID': 'c1dfd96eea'}, globalenv=globalenv),
+  linux_cxx("TOOLSET=clang COMPILER=clang++ CXXSTD=03,11 Job 7", "clang++", packages="", buildtype="boost", buildscript="drone", image=linuxglobalimage, environment={'TOOLSET': 'clang', 'COMPILER': 'clang++', 'CXXSTD': '03,11', 'DRONE_JOB_UUID': '902ba3cda1'}, globalenv=globalenv),
+  linux_cxx("TOOLSET=clang COMPILER=clang++-3.5 CXXSTD=03, Job 8", "clang++-3.5", packages="clang-3.5 libstdc++-4.9-dev", llvm_os="precise", llvm_ver="3.5", buildtype="boost", buildscript="drone", image=linuxglobalimage, environment={'TOOLSET': 'clang', 'COMPILER': 'clang++-3.5', 'CXXSTD': '03,11,14,1z', 'DRONE_JOB_UUID': 'fe5dbbcea5'}, globalenv=globalenv),
+  linux_cxx("TOOLSET=clang COMPILER=clang++-3.6 CXXSTD=03, Job 9", "clang++-3.6", packages="clang-3.6", llvm_os="precise", llvm_ver="3.6", buildtype="boost", buildscript="drone", image=linuxglobalimage, environment={'TOOLSET': 'clang', 'COMPILER': 'clang++-3.6', 'CXXSTD': '03,11,14,1z', 'DRONE_JOB_UUID': '0ade7c2cf9'}, globalenv=globalenv),
+  linux_cxx("TOOLSET=clang COMPILER=clang++-3.7 CXXSTD=03, Job 10", "clang++-3.7", packages="clang-3.7", llvm_os="precise", llvm_ver="3.7", buildtype="boost", buildscript="drone", image=linuxglobalimage, environment={'TOOLSET': 'clang', 'COMPILER': 'clang++-3.7', 'CXXSTD': '03,11,14,1z', 'DRONE_JOB_UUID': 'b1d5781111'}, globalenv=globalenv),
+  linux_cxx("TOOLSET=clang COMPILER=clang++-3.8 CXXSTD=03, Job 11", "clang++-3.8", packages="clang-3.8 libstdc++-4.9-dev", llvm_os="precise", llvm_ver="3.8", buildtype="boost", buildscript="drone", image=linuxglobalimage, environment={'TOOLSET': 'clang', 'COMPILER': 'clang++-3.8', 'CXXSTD': '03,11,14,1z', 'DRONE_JOB_UUID': '17ba079149'}, globalenv=globalenv),
+  linux_cxx("TOOLSET=clang COMPILER=clang++-3.9 CXXSTD=03, Job 12", "clang++-3.9", packages="clang-3.9 libstdc++-4.9-dev", llvm_os="precise", llvm_ver="3.9", buildtype="boost", buildscript="drone", image=linuxglobalimage, environment={'TOOLSET': 'clang', 'COMPILER': 'clang++-3.9', 'CXXSTD': '03,11,14,1z', 'DRONE_JOB_UUID': '7b52009b64'}, globalenv=globalenv),
+  linux_cxx("TOOLSET=clang COMPILER=clang++-4.0 CXXSTD=03, Job 13", "clang++-4.0", packages="clang-4.0", llvm_os="trusty", llvm_ver="4.0", buildtype="boost", buildscript="drone", image="cppalliance/droneubuntu1404:1", environment={'TOOLSET': 'clang', 'COMPILER': 'clang++-4.0', 'CXXSTD': '03,11,14,1z', 'DRONE_JOB_UUID': 'bd307a3ec3'}, globalenv=globalenv),
+  linux_cxx("TOOLSET=clang COMPILER=clang++-5.0 CXXSTD=03, Job 14", "clang++-5.0", packages="clang-5.0", llvm_os="trusty", llvm_ver="5.0", buildtype="boost", buildscript="drone", image="cppalliance/droneubuntu1404:1", environment={'TOOLSET': 'clang', 'COMPILER': 'clang++-5.0', 'CXXSTD': '03,11,14,1z', 'DRONE_JOB_UUID': 'fa35e19212'}, globalenv=globalenv),
+  osx_cxx("TOOLSET=clang COMPILER=clang++ CXXSTD=03,11,1 Job 15", "clang++", packages="", buildtype="boost", buildscript="drone", environment={'TOOLSET': 'clang', 'COMPILER': 'clang++', 'CXXSTD': '03,11,14,1z', 'DRONE_JOB_UUID': 'f1abd67035'}, globalenv=globalenv),
+    ]
+
+# from https://github.com/boostorg/boost-ci
+load("@boost_ci//ci/drone/:functions.star", "linux_cxx","windows_cxx","osx_cxx","freebsd_cxx")

.drone/drone.sh

@@ -0,0 +1,37 @@
+#!/bin/bash
+
+# Copyright 2020 Rene Rivera, Sam Darwin
+# Distributed under the Boost Software License, Version 1.0.
+# (See accompanying file LICENSE.txt or copy at http://boost.org/LICENSE_1_0.txt)
+
+set -e
+export TRAVIS_BUILD_DIR=$(pwd)
+export DRONE_BUILD_DIR=$(pwd)
+export TRAVIS_BRANCH=$DRONE_BRANCH
+export VCS_COMMIT_ID=$DRONE_COMMIT
+export GIT_COMMIT=$DRONE_COMMIT
+export REPO_NAME=$DRONE_REPO
+export PATH=~/.local/bin:/usr/local/bin:$PATH
+
+if [ "$DRONE_JOB_BUILDTYPE" == "boost" ]; then
+
+echo '==================================> INSTALL'
+
+BOOST_BRANCH=develop && [ "$TRAVIS_BRANCH" == "master" ] && BOOST_BRANCH=master || true
+cd ..
+git clone -b $BOOST_BRANCH --depth 1 https://github.com/boostorg/boost.git boost-root
+cd boost-root
+git submodule update --init tools/build
+git submodule update --init libs/config
+git submodule update --init tools/boostdep
+cp -r $TRAVIS_BUILD_DIR/* libs/optional
+python tools/boostdep/depinst/depinst.py optional
+./bootstrap.sh
+./b2 headers
+
+echo '==================================> SCRIPT'
+
+echo "using $TOOLSET : : $COMPILER ;" > ~/user-config.jam
+./b2 libs/optional/test toolset=$TOOLSET cxxstd=$CXXSTD
+
+fi

.github/workflows/ci.yml

@@ -0,0 +1,391 @@
+name: GitHub Actions CI
+
+on:
+  pull_request:
+  push:
+    branches:
+      - master
+      - develop
+      - githubactions*
+      - feature/**
+      - fix/**
+      - pr/**
+
+jobs:
+  posix:
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - name: "TOOLSET=gcc COMPILER=g++ CXXSTD=03,11 Job 0"
+            buildtype: "boost"
+            packages: ""
+            packages_to_remove: ""
+            os: "ubuntu-20.04"
+            container: "ubuntu:16.04"
+            cxx: "g++"
+            sources: ""
+            llvm_os: ""
+            llvm_ver: ""
+            toolset: "gcc"
+            compiler: "g++"
+            cxxstd: "03,11"
+          - name: "TOOLSET=gcc COMPILER=g++-4.7 CXXSTD=03,11 Job 1"
+            buildtype: "boost"
+            packages: "g++-4.7"
+            packages_to_remove: ""
+            os: "ubuntu-20.04"
+            container: "ubuntu:16.04"
+            cxx: "g++-4.7"
+            sources: ""
+            llvm_os: ""
+            llvm_ver: ""
+            toolset: "gcc"
+            compiler: "g++-4.7"
+            cxxstd: "03,11"
+          - name: "TOOLSET=gcc COMPILER=g++-4.8 CXXSTD=03,11 Job 2"
+            buildtype: "boost"
+            packages: "g++-4.8"
+            packages_to_remove: ""
+            os: "ubuntu-20.04"
+            container: "ubuntu:16.04"
+            cxx: "g++-4.8"
+            sources: ""
+            llvm_os: ""
+            llvm_ver: ""
+            toolset: "gcc"
+            compiler: "g++-4.8"
+            cxxstd: "03,11"
+          - name: "TOOLSET=gcc COMPILER=g++-4.9 CXXSTD=03,11 Job 3"
+            buildtype: "boost"
+            packages: "g++-4.9"
+            packages_to_remove: ""
+            os: "ubuntu-20.04"
+            container: "ubuntu:16.04"
+            cxx: "g++-4.9"
+            sources: ""
+            llvm_os: ""
+            llvm_ver: ""
+            toolset: "gcc"
+            compiler: "g++-4.9"
+            cxxstd: "03,11"
+          - name: "TOOLSET=gcc COMPILER=g++-5 CXXSTD=03,11,14,1z Job 4"
+            buildtype: "boost"
+            packages: "g++-5"
+            packages_to_remove: ""
+            os: "ubuntu-20.04"
+            container: "ubuntu:16.04"
+            cxx: "g++-5"
+            sources: ""
+            llvm_os: ""
+            llvm_ver: ""
+            toolset: "gcc"
+            compiler: "g++-5"
+            cxxstd: "03,11,14,1z"
+          - name: "TOOLSET=gcc COMPILER=g++-6 CXXSTD=03,11,14,1z Job 5"
+            buildtype: "boost"
+            packages: "g++-6"
+            packages_to_remove: ""
+            os: "ubuntu-20.04"
+            container: "ubuntu:16.04"
+            cxx: "g++-6"
+            sources: ""
+            llvm_os: ""
+            llvm_ver: ""
+            toolset: "gcc"
+            compiler: "g++-6"
+            cxxstd: "03,11,14,1z"
+          - name: "TOOLSET=gcc COMPILER=g++-7 CXXSTD=03,11,14,17 Job 6"
+            buildtype: "boost"
+            packages: "g++-7"
+            packages_to_remove: ""
+            os: "ubuntu-20.04"
+            container: "ubuntu:16.04"
+            cxx: "g++-7"
+            sources: ""
+            llvm_os: ""
+            llvm_ver: ""
+            toolset: "gcc"
+            compiler: "g++-7"
+            cxxstd: "03,11,14,17"
+          - name: "TOOLSET=clang COMPILER=clang++ CXXSTD=03,11 Job 7"
+            buildtype: "boost"
+            packages: ""
+            packages_to_remove: ""
+            os: "ubuntu-18.04"
+            cxx: "clang++"
+            sources: ""
+            llvm_os: ""
+            llvm_ver: ""
+            toolset: "clang"
+            compiler: "clang++"
+            cxxstd: "03,11"
+          - name: "TOOLSET=clang COMPILER=clang++-3.5 CXXSTD=03, Job 8"
+            buildtype: "boost"
+            packages: "clang-3.5 libstdc++-4.9-dev"
+            packages_to_remove: ""
+            os: "ubuntu-20.04"
+            container: "ubuntu:16.04"
+            cxx: "clang++-3.5"
+            sources: ""
+            llvm_os: "precise"
+            llvm_ver: "3.5"
+            toolset: "clang"
+            compiler: "clang++-3.5"
+            cxxstd: "03,11,14"
+          - name: "TOOLSET=clang COMPILER=clang++-3.6 CXXSTD=03, Job 9"
+            buildtype: "boost"
+            packages: "clang-3.6"
+            packages_to_remove: ""
+            os: "ubuntu-20.04"
+            container: "ubuntu:16.04"
+            cxx: "clang++-3.6"
+            sources: ""
+            llvm_os: "precise"
+            llvm_ver: "3.6"
+            toolset: "clang"
+            compiler: "clang++-3.6"
+            cxxstd: "03,11,14"
+          - name: "TOOLSET=clang COMPILER=clang++-3.7 CXXSTD=03, Job 10"
+            buildtype: "boost"
+            packages: "clang-3.7"
+            packages_to_remove: ""
+            os: "ubuntu-20.04"
+            container: "ubuntu:16.04"
+            cxx: "clang++-3.7"
+            sources: ""
+            llvm_os: "precise"
+            llvm_ver: "3.7"
+            toolset: "clang"
+            compiler: "clang++-3.7"
+            cxxstd: "03,11,14"
+          - name: "TOOLSET=clang COMPILER=clang++-3.8 CXXSTD=03, Job 11"
+            buildtype: "boost"
+            packages: "clang-3.8 libstdc++-4.9-dev"
+            packages_to_remove: ""
+            os: "ubuntu-20.04"
+            container: "ubuntu:16.04"
+            cxx: "clang++-3.8"
+            sources: ""
+            llvm_os: "precise"
+            llvm_ver: "3.8"
+            toolset: "clang"
+            compiler: "clang++-3.8"
+            cxxstd: "03,11,14"
+          - name: "TOOLSET=clang COMPILER=clang++-3.9 CXXSTD=03, Job 12"
+            buildtype: "boost"
+            packages: "clang-3.9 libstdc++-4.9-dev"
+            packages_to_remove: ""
+            os: "ubuntu-20.04"
+            container: "ubuntu:16.04"
+            cxx: "clang++-3.9"
+            sources: ""
+            llvm_os: "precise"
+            llvm_ver: "3.9"
+            toolset: "clang"
+            compiler: "clang++-3.9"
+            cxxstd: "03,11,14"
+          - name: "TOOLSET=clang COMPILER=clang++-4.0 CXXSTD=03, Job 13"
+            buildtype: "boost"
+            packages: "clang-4.0"
+            packages_to_remove: ""
+            os: "ubuntu-20.04"
+            container: "ubuntu:14.04"
+            cxx: "clang++-4.0"
+            sources: ""
+            llvm_os: "trusty"
+            llvm_ver: "4.0"
+            toolset: "clang"
+            compiler: "clang++-4.0"
+            cxxstd: "03,11,14"
+          - name: "TOOLSET=clang COMPILER=clang++-5.0 CXXSTD=03, Job 14"
+            buildtype: "boost"
+            packages: "clang-5.0"
+            packages_to_remove: ""
+            os: "ubuntu-20.04"
+            container: "ubuntu:14.04"
+            cxx: "clang++-5.0"
+            sources: ""
+            llvm_os: "trusty"
+            llvm_ver: "5.0"
+            toolset: "clang"
+            compiler: "clang++-5.0"
+            cxxstd: "03,11,14,1z"
+
+    runs-on: ${{ matrix.os }}
+    container: ${{ matrix.container }}
+
+    steps:
+      - name: Check if running in container
+        if: matrix.container != ''
+        run: echo "GHA_CONTAINER=${{ matrix.container }}" >> $GITHUB_ENV
+      - name: If running in container, upgrade packages
+        if: matrix.container != ''
+        run: |
+            apt-get -o Acquire::Retries=3 update && DEBIAN_FRONTEND=noninteractive apt-get -y install tzdata && apt-get -o Acquire::Retries=3 install -y sudo software-properties-common wget curl apt-transport-https make apt-file sudo unzip libssl-dev build-essential autotools-dev autoconf automake g++ libc++-helpers python ruby cpio gcc-multilib g++-multilib pkgconf python3 ccache libpython-dev
+            sudo apt-add-repository ppa:git-core/ppa
+            sudo apt-get -o Acquire::Retries=3 update && apt-get -o Acquire::Retries=3 -y install git
+            python_version=$(python3 -c 'import sys; print("{0.major}.{0.minor}".format(sys.version_info))')
+            sudo wget https://bootstrap.pypa.io/pip/$python_version/get-pip.py
+            sudo python3 get-pip.py
+            sudo /usr/local/bin/pip install cmake
+
+      - uses: actions/checkout@v2
+
+      - name: linux
+        shell: bash
+        env:
+          CXX: ${{ matrix.cxx }}
+          SOURCES: ${{ matrix.sources }}
+          LLVM_OS: ${{ matrix.llvm_os }}
+          LLVM_VER: ${{ matrix.llvm_ver }}
+          PACKAGES: ${{ matrix.packages }}
+          PACKAGES_TO_REMOVE: ${{ matrix.packages_to_remove }}
+          JOB_BUILDTYPE: ${{ matrix.buildtype }}
+          TOOLSET: ${{ matrix.toolset }}
+          COMPILER: ${{ matrix.compiler }}
+          CXXSTD: ${{ matrix.cxxstd }}
+          TRAVIS_BRANCH: ${{ github.base_ref }}
+          TRAVIS_OS_NAME: "linux"
+        run: |
+          echo '==================================> SETUP'
+          echo '==================================> PACKAGES'
+          set -e
+          if [ -n "$PACKAGES_TO_REMOVE" ]; then sudo apt-get purge -y $PACKAGES_TO_REMOVE; fi
+          echo ">>>>> APT: REPO.."
+          for i in {1..3}; do sudo -E apt-add-repository -y "ppa:ubuntu-toolchain-r/test" && break || sleep 2; done
+          
+          if test -n "${LLVM_OS}" ; then
+              wget -O - https://apt.llvm.org/llvm-snapshot.gpg.key | sudo apt-key add -
+              if test -n "${LLVM_VER}" ; then
+                  sudo -E apt-add-repository "deb http://apt.llvm.org/${LLVM_OS}/ llvm-toolchain-${LLVM_OS}-${LLVM_VER} main"
+              else
+                  # Snapshot (i.e. trunk) build of clang
+                  sudo -E apt-add-repository "deb http://apt.llvm.org/${LLVM_OS}/ llvm-toolchain-${LLVM_OS} main"
+              fi
+          fi
+          echo ">>>>> APT: UPDATE.."
+          sudo -E apt-get -o Acquire::Retries=3 update
+          if test -n "${SOURCES}" ; then
+              echo ">>>>> APT: INSTALL SOURCES.."
+              for SOURCE in $SOURCES; do
+                  sudo -E apt-add-repository ppa:$SOURCE
+              done
+          fi
+          echo ">>>>> APT: INSTALL ${PACKAGES}.."
+          sudo -E DEBIAN_FRONTEND=noninteractive apt-get -o Acquire::Retries=3 -y --no-install-suggests --no-install-recommends install ${PACKAGES}
+
+          echo '==================================> INSTALL AND COMPILE'
+          set -e
+          export TRAVIS_BUILD_DIR=$(pwd)
+          export TRAVIS_BRANCH=${TRAVIS_BRANCH:-$(echo $GITHUB_REF | awk 'BEGIN { FS = "/" } ; { print $3 }')}
+          export VCS_COMMIT_ID=$GITHUB_SHA
+          export GIT_COMMIT=$GITHUB_SHA
+          export REPO_NAME=$(basename $GITHUB_REPOSITORY)
+          export USER=$(whoami)
+          export CC=${CC:-gcc}
+          export PATH=~/.local/bin:/usr/local/bin:$PATH
+
+          if [ "$JOB_BUILDTYPE" == "boost" ]; then
+
+          echo '==================================> INSTALL'
+
+          BOOST_BRANCH=develop && [ "$TRAVIS_BRANCH" == "master" ] && BOOST_BRANCH=master || true
+          cd ..
+          git clone -b $BOOST_BRANCH --depth 1 https://github.com/boostorg/boost.git boost-root
+          cd boost-root
+          git submodule update --init tools/build
+          git submodule update --init libs/config
+          git submodule update --init tools/boostdep
+          cp -r $TRAVIS_BUILD_DIR/* libs/optional
+          python tools/boostdep/depinst/depinst.py optional
+          ./bootstrap.sh
+          ./b2 headers
+
+          echo '==================================> SCRIPT'
+
+          echo "using $TOOLSET : : $COMPILER ;" > ~/user-config.jam
+          ./b2 libs/optional/test toolset=$TOOLSET cxxstd=$CXXSTD
+
+          fi
+  osx:
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - name: "TOOLSET=clang COMPILER=clang++ CXXSTD=03,11,1 Job 15"
+            buildtype: "boost"
+            packages: ""
+            os: "macos-10.15"
+            cxx: "clang++"
+            sources: ""
+            llvm_os: ""
+            llvm_ver: ""
+            xcode_version: 11.7
+            toolset: "clang"
+            compiler: "clang++"
+            cxxstd: "03,11,14,1z"
+
+    runs-on: ${{ matrix.os }}
+
+    steps:
+      - uses: actions/checkout@v2
+
+      - name: Set DEVELOPER_DIR
+        if: matrix.xcode_version != ''
+        run: echo "DEVELOPER_DIR=/Applications/Xcode_${{ matrix.xcode_version }}.app/Contents/Developer" >> $GITHUB_ENV
+      - name: Test DEVELOPER_DIR
+        run: echo $DEVELOPER_DIR
+
+      - name: "osx"
+        shell: bash
+        env:
+          CXX: ${{ matrix.cxx }}
+          SOURCES: ${{ matrix.sources }}
+          LLVM_OS: ${{ matrix.llvm_os }}
+          LLVM_VER: ${{ matrix.llvm_ver }}
+          PACKAGES: ${{ matrix.packages }}
+          JOB_BUILDTYPE: ${{ matrix.buildtype }}
+          TOOLSET: ${{ matrix.toolset }}
+          COMPILER: ${{ matrix.compiler }}
+          CXXSTD: ${{ matrix.cxxstd }}
+          TRAVIS_BRANCH: ${{ github.base_ref }}
+          TRAVIS_OS_NAME: "osx"
+        run: |
+          echo '==================================> SETUP'
+          set -e
+          sudo mv /Library/Developer/CommandLineTools /Library/Developer/CommandLineTools.bck
+          echo '==================================> PACKAGES'
+          echo '==================================> INSTALL AND COMPILE'
+          set -e
+          export TRAVIS_BUILD_DIR=$(pwd)
+          export TRAVIS_BRANCH=${TRAVIS_BRANCH:-$(echo $GITHUB_REF | awk 'BEGIN { FS = "/" } ; { print $3 }')}
+          export VCS_COMMIT_ID=$GITHUB_SHA
+          export GIT_COMMIT=$GITHUB_SHA
+          export REPO_NAME=$(basename $GITHUB_REPOSITORY)
+          export USER=$(whoami)
+          export CC=${CC:-gcc}
+          export PATH=~/.local/bin:/usr/local/bin:$PATH
+
+          if [ "$JOB_BUILDTYPE" == "boost" ]; then
+
+          echo '==================================> INSTALL'
+
+          BOOST_BRANCH=develop && [ "$TRAVIS_BRANCH" == "master" ] && BOOST_BRANCH=master || true
+          cd ..
+          git clone -b $BOOST_BRANCH --depth 1 https://github.com/boostorg/boost.git boost-root
+          cd boost-root
+          git submodule update --init tools/build
+          git submodule update --init libs/config
+          git submodule update --init tools/boostdep
+          cp -r $TRAVIS_BUILD_DIR/* libs/optional
+          python tools/boostdep/depinst/depinst.py optional
+          ./bootstrap.sh
+          ./b2 headers
+
+          echo '==================================> SCRIPT'
+
+          echo "using $TOOLSET : : $COMPILER ;" > ~/user-config.jam
+          ./b2 libs/optional/test toolset=$TOOLSET cxxstd=$CXXSTD
+
+          fi

CMakeLists.txt

@@ -1,12 +1,9 @@
 # Copyright 2019 Mike Dev
 # Distributed under the Boost Software License, Version 1.0.
 # See accompanying file LICENSE_1_0.txt or copy at https://www.boost.org/LICENSE_1_0.txt
-#
-# NOTE: CMake support for Boost.Optional is currently experimental at best
-#       and the interface is likely to change in the future
 
-cmake_minimum_required( VERSION 3.5 )
-project( BoostOptional )
+cmake_minimum_required( VERSION 3.5...3.20 )
+project( boost_optional VERSION "${BOOST_SUPERPROJECT_VERSION}" LANGUAGES CXX )
 
 add_library( boost_optional INTERFACE )
 add_library( Boost::optional ALIAS boost_optional )

doc/00_optional.qbk

@@ -2,7 +2,7 @@
     [quickbook 1.4]
     [authors [Cacciola Carballal, Fernando Luis]]
     [copyright 2003-2007 Fernando Luis Cacciola Carballal]
-    [copyright 2014-2018 Andrzej Krzemieński]
+    [copyright 2014-2022 Andrzej Krzemieński]
     [category miscellaneous]
     [id optional]
     [dirname optional]
@@ -38,10 +38,10 @@ Distributed under the Boost Software License, Version 1.0.
 [/ Other web resources ]
 
 [def __HASKELL__ [@http://www.haskell.org/ Haskell]]
-[def __SGI_DEFAULT_CONSTRUCTIBLE__ [@http://www.sgi.com/tech/stl/DefaultConstructible.html `DefaultConstructible`]]
-[def __SGI_LESS_THAN_COMPARABLE__ [@http://www.sgi.com/tech/stl/LessThanComparable.html `LessThanComparable`]]
-[def __SGI_EQUALITY_COMPARABLE__ [@http://www.sgi.com/tech/stl/EqualityComparable.html `EqualityComparable`]]
-[def __SGI_GENERATOR__ [@http://www.sgi.com/tech/stl/Generator.html `Generator`]]
+[def __STD_DEFAULT_CONSTRUCTIBLE__ [@https://en.cppreference.com/w/cpp/named_req/DefaultConstructible `DefaultConstructible`]]
+[def __STD_LESS_THAN_COMPARABLE__ [@https://en.cppreference.com/w/cpp/named_req/LessThanComparable `LessThanComparable`]]
+[def __STD_EQUALITY_COMPARABLE__ [@https://en.cppreference.com/w/cpp/named_req/EqualityComparable `EqualityComparable`]]
+[def __SGI_GENERATOR__ [@http://www.rrsd.com/software_development/stl/stl/Generator.html `Generator`]]
 
 
 [/ Icons ]
@@ -61,7 +61,7 @@ Suppose we want to read a parameter form a config file which represents some int
 This is how you solve it with `boost::optional`:
 
     #include <boost/optional.hpp>
-    
+
     boost::optional<int> getConfigParam(std::string name);  // return either an int or a `not-an-int`
 
     int main()
@@ -71,7 +71,7 @@ This is how you solve it with `boost::optional`:
       else
         runWithNoMax();
     }
- 
+
 [endsect]
 
 [include 01_quick_start.qbk]
@@ -102,5 +102,3 @@ This is how you solve it with `boost::optional`:
 [include 90_dependencies.qbk]
 [include 91_relnotes.qbk]
 [include 92_acknowledgments.qbk]
-
-

doc/01_quick_start.qbk

@@ -25,7 +25,7 @@ All necessary functionality can be included with one header `<boost/optional.hpp
     boost::optional<int> oi = convert(text); // move-construct
     if (oi)                                  // contextual conversion to bool
       int i = *oi;                           // operator*
-    
+
 In order to test if `optional` contains a value, we use the contextual conversion to type `bool`. Because of this we can combine the initialization of the optional object and the test into one instruction:
 
     if (boost::optional<int> oi = convert(text))
@@ -34,7 +34,7 @@ In order to test if `optional` contains a value, we use the contextual conversio
 We extract the contained value with `operator*` (and with `operator->` where it makes sense). An attempt to extract the contained value of an uninitialized optional object is an ['undefined behaviour] (UB). This implementation guards the call with `BOOST_ASSERT`. Therefore you should be sure that the contained value is there before extracting. For instance, the following code is reasonably UB-safe:
 
     int i = *convert("100");
-    
+
 This is because we know that string value `"100"` converts to a valid value of `int`. If you do not like this potential UB, you can use an alternative way of extracting the contained value:
 
     try {
@@ -47,15 +47,15 @@ This is because we know that string value `"100"` converts to a valid value of `
 This version throws an exception upon an attempt to access a non-existent contained value. If your way of dealing with the missing value is to use some default, like `0`, there exists a yet another alternative:
 
     int k = convert(text).value_or(0);
-    
+
 This uses the `atoi`-like approach to conversions: if `text` does not represent an integral number just return `0`. Finally, you can provide a callback to be called when trying to access the contained value fails:
 
     int fallback_to_default()
     {
-      cerr << "could not convert; using -1 instead" << endl; 
+      cerr << "could not convert; using -1 instead" << endl;
       return -1;
     }
-    
+
     int l = convert(text).value_or_eval(fallback_to_default);
 
 This will call the provided callback and return whatever the callback returns. The callback can have side effects: they will only be observed when the optional object does not contain a value.
@@ -63,7 +63,7 @@ This will call the provided callback and return whatever the callback returns. T
 Now, let's consider how function `convert` can be implemented.
 
     boost::optional<int> convert(const std::string& text)
-    {  
+    {
       std::stringstream s(text);
       int i;
       if ((s >> i) && s.get() == std::char_traits<char>::eof())
@@ -72,7 +72,7 @@ Now, let's consider how function `convert` can be implemented.
         return boost::none;
     }
 
-Observe the two return statements. `return i` uses the converting constructor that can create `optional<T>` from `T`. Thus constructed optional object is initialized and its value is a copy of `i`. The other return statement uses another converting constructor from a special tag `boost::none`. It is used to indicate that we want to create an uninitialized optional object. 
+Observe the two return statements. `return i` uses the converting constructor that can create `optional<T>` from `T`. Thus constructed optional object is initialized and its value is a copy of `i`. The other return statement uses another converting constructor from a special tag `boost::none`. It is used to indicate that we want to create an uninitialized optional object.
 
 [endsect]
 
@@ -91,7 +91,7 @@ We could write function `convert` in a slightly different manner, so that it has
       return ans;
     }
 
-The default constructor of `optional` creates an unitialized optional object. Unlike with `int`s you cannot have an `optional<int>` in an indeterminate state. Its state is always well defined. Instruction `ans = i` initializes the optional object. It uses the 'mixed' assignment from `int`. In general, for `optional<T>`, when an assignment from `T` is invoked, it can do two things. If the optional object is not initialized (our case here), it initializes the contained value using `T`'s copy constructor. If the optional object is already initialized, it assigns the new value to it using `T`'s copy assignment.      
+The default constructor of `optional` creates an unitialized optional object. Unlike with `int`s you cannot have an `optional<int>` in an indeterminate state. Its state is always well defined. Instruction `ans = i` initializes the optional object. It uses the 'mixed' assignment from `int`. In general, for `optional<T>`, when an assignment from `T` is invoked, it can do two things. If the optional object is not initialized (our case here), it initializes the contained value using `T`'s copy constructor. If the optional object is already initialized, it assigns the new value to it using `T`'s copy assignment.
 [endsect]
 
 [section Optional data members]
@@ -101,20 +101,20 @@ Suppose we want to implement a ['lazy load] optimization. This is because we do
     class Widget
     {
       mutable boost::optional<const Resource> resource_;
-      
+
     public:
       Widget() {}
-      
+
       const Resource& getResource() const // not thread-safe
       {
         if (resource_ == boost::none)
             resource_.emplace("resource", "arguments");
-        
+
         return *resource_;
       }
     };
-    
-`optional`'s default constructor creates an uninitialized optional. No call to `Resource`'s default constructor is attempted. `Resource` doesn't have to be __SGI_DEFAULT_CONSTRUCTIBLE__. In function `getResource` we first check if `resource_` is initialized. This time we do not use the contextual conversion to `bool`, but a comparison with `boost::none`. These two ways are equivalent. Function `emplace` initializes the optional in-place by perfect-forwarding the arguments to the constructor of `Resource`. No copy- or move-construction is involved here. `Resource` doesn't even have to be `MoveConstructible`. 
+
+`optional`'s default constructor creates an uninitialized optional. No call to `Resource`'s default constructor is attempted. `Resource` doesn't have to be __STD_DEFAULT_CONSTRUCTIBLE__. In function `getResource` we first check if `resource_` is initialized. This time we do not use the contextual conversion to `bool`, but a comparison with `boost::none`. These two ways are equivalent. Function `emplace` initializes the optional in-place by perfect-forwarding the arguments to the constructor of `Resource`. No copy- or move-construction is involved here. `Resource` doesn't even have to be `MoveConstructible`.
 
 [note Function `emplace` is only available on compilers that support rvalue references and variadic templates. If your compiler does not support these features and you still need to avoid any move-constructions, use [link boost_optional.tutorial.in_place_factories In-Place Factories].]
 
@@ -125,17 +125,17 @@ Suppose we want to implement a ['lazy load] optimization. This is because we do
 Suppose we have class `Date`, which does not have a default constructor: there is no good candidate for a default date. We have a function that returns two dates in form of a `boost::tuple`:
 
     boost::tuple<Date, Date> getPeriod();
-    
+
 In other place we want to use the result of `getPeriod`, but want the two dates to be named: `begin` and `end`. We want to implement something like 'multiple return values':
 
     Date begin, end; // Error: no default ctor!
     boost::tie(begin, end) = getPeriod();
-    
+
 The second line works already, this is the capability of __BOOST_TUPLE__ library, but the first line won't work. We could set some invented initial dates, but it is confusing and may be an unacceptable cost, given that these values will be overwritten in the next line anyway. This is where `optional` can help:
 
     boost::optional<Date> begin, end;
     boost::tie(begin, end) = getPeriod();
-    
+
 It works because inside `boost::tie` a move-assignment from `T` is invoked on `optional<T>`, which internally calls a move-constructor of `T`.
 [endsect]
 
@@ -144,15 +144,17 @@ It works because inside `boost::tie` a move-assignment from `T` is invoked on `o
 Suppose you want to ask users to choose some number (an `int`). One of the valid responses is to choose nothing, which is represented by an uninitialized `optional<int>`. You want to make a histogram showing how many times each choice was made. You can use an `std::map`:
 
     std::map<boost::optional<int>, int> choices;
-  
+
     for (int i = 0; i < LIMIT; ++i) {
       boost::optional<int> choice = readChoice();
       ++choices[choice];
     }
-    
-This works because `optional<T>` is __SGI_LESS_THAN_COMPARABLE__ whenever `T` is __SGI_LESS_THAN_COMPARABLE__. In this case the state of being uninitialized is treated as a yet another value of `T`, which is compared less than any value of `T`.
+
+This works because `optional<T>` is __STD_LESS_THAN_COMPARABLE__ whenever `T` is __STD_LESS_THAN_COMPARABLE__.
+In this case the state of being uninitialized is treated as a yet another value of `T`,
+which is compared less than any value of `T`.
+`optional<T>` can also be stored as a key in `std::unordered_map` and `std::unordered_set`
+as it provides specializations for `std::hash`.
 [endsect]
 
 [endsect]
-
- 

doc/12_when_to_use.qbk

@@ -11,7 +11,7 @@ Here, having received an empty `vec` and having no `size_t` to return is not a [
 
 Another typical situation is to indicate that we do not have a value yet, but we expect to have it later. This notion can be used in implementing solutions like lazy initialization or a two-phase initialization.
 
-`optional` can be used to take a non-__SGI_DEFAULT_CONSTRUCTIBLE__ type `T` and create a sibling type with a default constructor. This is a way to add a ['null-state] to any type that doesn't have it already.
+`optional` can be used to take a non-__STD_DEFAULT_CONSTRUCTIBLE__ type `T` and create a sibling type with a default constructor. This is a way to add a ['null-state] to any type that doesn't have it already.
 
 Sometimes type `T` already provides a built-in null-state, but it may still be useful to wrap it into `optional`. Consider `std::string`. When you read a piece of text from a GUI form or a DB table, it is hardly ever that the empty string indicates anything else but a missing text. And some data bases do not even distinguish between a null string entry and a non-null string of length 0. Still, it may be practical to use `optional<string>` to indicate in the returned type that we want to treat the empty string in a special dedicated program path:
 

doc/13_relational_operators.qbk

@@ -1,18 +1,18 @@
 
 [section Relational operators]
 
-Type `optional<T>` is __SGI_EQUALITY_COMPARABLE__ whenever `T` is __SGI_EQUALITY_COMPARABLE__. Two optional objects containing a value compare in the same way as their contained values. The uninitialized state of `optional<T>` is treated as a distinct value, equal to itself, and unequal to any value of type `T`:
+Type `optional<T>` is __STD_EQUALITY_COMPARABLE__ whenever `T` is __STD_EQUALITY_COMPARABLE__. Two optional objects containing a value compare in the same way as their contained values. The uninitialized state of `optional<T>` is treated as a distinct value, equal to itself, and unequal to any value of type `T`:
 
     boost::optional<int> oN = boost::none;
     boost::optional<int> o0 = 0;
     boost::optional<int> o1 = 1;
-    
+
     assert(oN != o0);
     assert(o1 != oN);
     assert(o0 != o1);
     assert(oN == oN);
     assert(o0 == o0);
-    
+
 The converting constructor from `T` as well as from `boost::none` implies the existence and semantics of the mixed comparison between `T` and `optional<T>` as well as between `none_t` and `optionl<T>`:
 
     assert(oN != 0);
@@ -20,18 +20,18 @@ The converting constructor from `T` as well as from `boost::none` implies the ex
     assert(o0 != 1);
     assert(oN == boost::none);
     assert(o0 == 0);
-    
+
 This mixed comparison has a practical interpretation, which is occasionally useful:
 
     boost::optional<int> choice = ask_user();
     if (choice == 2)
         start_procedure_2();
-        
+
 In the above example, the meaning of the comparison is 'user chose number 2'. If user chose nothing, he didn't choose number 2.
 
-In case where `optional<T>` is compared to `none`, it is not required that `T` be __SGI_EQUALITY_COMPARABLE__.
+In case where `optional<T>` is compared to `none`, it is not required that `T` be __STD_EQUALITY_COMPARABLE__.
 
-In a similar manner, type `optional<T>` is __SGI_LESS_THAN_COMPARABLE__ whenever `T` is __SGI_LESS_THAN_COMPARABLE__. The optional object containing no value is compared less than any value of `T`. To illustrate this, if the default ordering of `size_t` is {`0`, `1`, `2`, ...}, the default ordering of `optional<size_t>` is {`boost::none`, `0`, `1`, `2`, ...}. This order does not have a practical interpretation. The goal is to have any semantically correct default ordering in order for `optional<T>` to be usable in ordered associative containers (wherever `T` is usable).  
+In a similar manner, type `optional<T>` is __STD_LESS_THAN_COMPARABLE__ whenever `T` is __STD_LESS_THAN_COMPARABLE__. The optional object containing no value is compared less than any value of `T`. To illustrate this, if the default ordering of `size_t` is {`0`, `1`, `2`, ...}, the default ordering of `optional<size_t>` is {`boost::none`, `0`, `1`, `2`, ...}. This order does not have a practical interpretation. The goal is to have any semantically correct default ordering in order for `optional<T>` to be usable in ordered associative containers (wherever `T` is usable).
 
 Mixed relational operators are the only case where the contained value of an optional object can be inspected without the usage of value accessing function (`operator*`, `value`, `value_or`).
 [endsect]

doc/17_gotchas.qbk

@@ -61,12 +61,12 @@ When an optional object that contains a value is moved from (is a source of move
     assert (opi);
     assert (*opi == nullptr);
 
-Quite a lot of people expect that when an object that contains a value is moved from, its contained value should be destroyed. This is not so, for performance reasons. Current semantics allow the implementation of `boost::opiotnal<T>` to be trivially copyable when `T` is trivial.
+Quite a lot of people expect that when an object that contains a value is moved from, its contained value should be destroyed. This is not so, for performance reasons. Current semantics allow the implementation of `boost::optional<T>` to be trivially copyable when `T` is trivial.
 [endsect]
 
 [section Mixed relational comparisons]
 
-Because `T` is convertible to `optional<T>` and because `opiotnal<T>` is __SGI_LESS_THAN_COMPARABLE__ when `T` is __SGI_LESS_THAN_COMPARABLE__,
+Because `T` is convertible to `optional<T>` and because `optional<T>` is __STD_LESS_THAN_COMPARABLE__ when `T` is __STD_LESS_THAN_COMPARABLE__,
 you can sometimes get an unexpected runtime result where you would rather expect a compiler error:
 
     optional<double> Flight_plan::weight(); // sometimes no weight can be returned
@@ -108,4 +108,4 @@ This is obviously redundant, but makes the warning disappear.
 
 [endsect]
 
-[endsect]
+[endsect]

doc/19_type_requirements.qbk

@@ -33,6 +33,6 @@ If `T` is `Moveable` (both __MOVE_CONSTRUCTIBLE__ and `MoveAssignable`) then `op
 
 Similarly, if `T` is `Copyable` (both __COPY_CONSTRUCTIBLE__ and `CopyAssignable`) then `optional<T>` is also `Copyable` and additionally can be constructed and assigned from an lvalue of type `T`.
 
-`T` ['is not] required to be __SGI_DEFAULT_CONSTRUCTIBLE__.
+`T` ['is not] required to be __STD_DEFAULT_CONSTRUCTIBLE__.
 
 [endsect]

doc/23_ref_optional_io.qbk

@@ -26,11 +26,11 @@ template <class CharType, class CharTrait, class T>
   template <class CharType, class CharTrait>
   std::basic_ostream<CharType, CharTrait>&
   operator<<(std::basic_ostream<CharType, CharTrait>& out, none_t const&); ``[link reference_operator_ostream_none __GO_TO__]``
-  
+
 template<class CharType, class CharTrait, class T>
   std::basic_istream<CharType, CharTrait>&
   operator>>(std::basic_istream<CharType, CharTrait>& in, optional<T>& v); ``[link reference_operator_istream __GO_TO__]``
-  
+
 } // namespace boost
 ```
 
@@ -43,8 +43,8 @@ template<class CharType, class CharTrait, class T>
 
 
 `template <class CharType, class CharTrait, class T>` [br]
-\u00A0\u00A0\u00A0\u00A0`std::basic_ostream<CharType, CharTrait>&` [br]
-\u00A0\u00A0\u00A0\u00A0`operator<<(std::basic_ostream<CharType, CharTrait>& out, optional<T> const& v);`
+ std::basic_ostream<CharType, CharTrait>&` [br]
+ operator<<(std::basic_ostream<CharType, CharTrait>& out, optional<T> const& v);`
 
 * [*Effect:] Outputs an implementation-defined string. The output contains the information about whether the optional object contains a value or not. If `v` contains a value, the output contains result of calling `out << *v`.
 * [*Returns:] `out`.
@@ -53,8 +53,8 @@ __SPACE__
 [#reference_operator_ostream_none]
 
 `template <class CharType, class CharTrait, class T>` [br]
-\u00A0\u00A0\u00A0\u00A0`std::basic_ostream<CharType, CharTrait>&` [br]
-\u00A0\u00A0\u00A0\u00A0`operator<<(std::basic_ostream<CharType, CharTrait>& out, none_t);`
+ std::basic_ostream<CharType, CharTrait>&` [br]
+ operator<<(std::basic_ostream<CharType, CharTrait>& out, none_t);`
 
 * [*Effect:] Outputs an implementation-defined string.
 * [*Returns:] `out`.
@@ -63,11 +63,11 @@ __SPACE__
 [#reference_operator_istream]
 
 `template <class CharType, class CharTrait, class T>` [br]
-\u00A0\u00A0\u00A0\u00A0`std::basic_ostream<CharType, CharTrait>&` [br]
-\u00A0\u00A0\u00A0\u00A0`operator>>(std::basic_istream<CharType, CharTrait>& in, optional<T>& v);`
+ std::basic_ostream<CharType, CharTrait>&` [br]
+ operator>>(std::basic_istream<CharType, CharTrait>& in, optional<T>& v);`
 
-* [*Requires:] `T` is __SGI_DEFAULT_CONSTRUCTIBLE__ and __MOVE_CONSTRUCTIBLE__.
-* [*Effect:] Reads the value of optional object from `in`. If the string representation indicates that the optional object should contain a value, `v` contains a value and its contained value is obtained as if by default-constructing an object `o` of type `T` and then calling `in >> o`; otherwise `v` does not contain a value, and the previously contained value (if any) has been destroyed. 
+* [*Requires:] `T` is __STD_DEFAULT_CONSTRUCTIBLE__ and __MOVE_CONSTRUCTIBLE__.
+* [*Effect:] Reads the value of optional object from `in`. If the string representation indicates that the optional object should contain a value, `v` contains a value and its contained value is obtained as if by default-constructing an object `o` of type `T` and then calling `in >> o`; otherwise `v` does not contain a value, and the previously contained value (if any) has been destroyed.
 * [*Returns:] `out`.
 
 [endsect]

doc/27_ref_optional_synopsis.qbk

@@ -73,6 +73,16 @@
 
     } // namespace boost
 
+    namespace std {
+
+    template <typename T>
+    struct hash<boost::optional<T> > ; ``[link reference_std_hash_spec __GO_TO__]``
+
+    template <typename T>
+    struct hash<boost::optional<T&> > ; ``[link reference_std_hash_spec __GO_TO__]``
+
+    } // namespace std
+
 
 [endsect]
 

doc/28_ref_optional_semantics.qbk

@@ -1216,7 +1216,7 @@ __SPACE__
 
 [: `bool operator == ( optional<T> const& x, optional<T> const& y );`]
 
-* [*Requires:] `T` shall meet requirements of __SGI_EQUALITY_COMPARABLE__.
+* [*Requires:] `T` shall meet requirements of __STD_EQUALITY_COMPARABLE__.
 * [*Returns:] If both `x` and `y` are initialized, `(*x == *y)`. If only
 `x` or `y` is initialized, `false`. If both are uninitialized, `true`.
 * [*Notes:] This definition guarantees that `optional<T>` not containing a value is compared unequal to any `optional<T>` containing any value, and equal to any other `optional<T>` not containing a value.
@@ -1249,7 +1249,7 @@ __SPACE__
 * [*Returns:] `(!y) ? false : (!x) ? true : *x < *y`.
 * [*Notes:] This definition guarantees that `optional<T>` not containing a value is ordered as less than any `optional<T>` containing any value, and equivalent to any other `optional<T>` not containing a value.
 Pointers have shallow relational operators while `optional` has deep relational operators. Do not use `operator<` directly in generic code
-which expect to be given either an `optional<T>` or a pointer; use __FUNCTION_LESS_POINTEES__ instead. `T` need not be __SGI_LESS_THAN_COMPARABLE__. Only single `operator<` is required. Other relational operations are defined in terms of this one. If `T`'s `operator<` satisfies the axioms of __SGI_LESS_THAN_COMPARABLE__ (transitivity, antisymmetry and irreflexivity), `optinal<T>` is __SGI_LESS_THAN_COMPARABLE__.
+which expect to be given either an `optional<T>` or a pointer; use __FUNCTION_LESS_POINTEES__ instead. `T` need not be __STD_LESS_THAN_COMPARABLE__. Only single `operator<` is required. Other relational operations are defined in terms of this one. If `T`'s `operator<` satisfies the axioms of __STD_LESS_THAN_COMPARABLE__ (transitivity, antisymmetry and irreflexivity), `optinal<T>` is __STD_LESS_THAN_COMPARABLE__.
 * [*Example:]
 ``
 optional<T> oN, oN_;
@@ -1310,7 +1310,7 @@ __SPACE__
 [: `bool operator == ( none_t, optional<T> const& x ) noexcept;`]
 
 * [*Returns:] `!x`.
-* [*Notes:] `T` need not meet requirements of __SGI_EQUALITY_COMPARABLE__.
+* [*Notes:] `T` need not meet requirements of __STD_EQUALITY_COMPARABLE__.
 
 
 __SPACE__
@@ -1408,3 +1408,37 @@ assert (addressof(*opt0) == addressof(y));
 ``
 
 [endsect]
+
+
+[section Detailed Semantics - std::hash Specializations]
+
+__SPACE__
+[#reference_std_hash_spec]
+
+``
+namespace std {
+
+template <typename T>
+struct hash<boost::optional<T> > ;
+
+template <typename T>
+struct hash<boost::optional<T&> > ;
+
+} // namespace std
+``
+
+The specialization `hash<optional<T>>` is enabled if and only if
+`hash<remove_­const_­t<T>>` is enabled. When enabled, for an object `o`
+of type `optional<T>`, if `o.has_­value() == true`, then `hash<optional<T>>()(o)`
+ evaluates to the same value as `hash<remove_­const_­t<T>>()(*o)`; otherwise it
+evaluates to an unspecified value.
+The member functions are not guaranteed to be `noexcept`.
+
+[caution
+You may get compiler errors when your program provides specializations for
+`std::hash<boost::optional<T>>`. If this happens, define macro
+`BOOST_OPTIONAL_CONFIG_DO_NOT_SPECIALIZE_STD_HASH` to suppress the specializations
+of `std::hash` in this library.
+]
+
+[endsect]

doc/91_relnotes.qbk

@@ -1,7 +1,7 @@
 [/
     Boost.Optional
 
-    Copyright (c) 2015 - 2018 Andrzej Krzemienski
+    Copyright (c) 2015 - 2022 Andrzej Krzemienski
 
     Distributed under the Boost Software License, Version 1.0.
     (See accompanying file LICENSE_1_0.txt or copy at
@@ -11,6 +11,22 @@
 
 [section:relnotes Release Notes]
 
+[heading Boost Release 1.80]
+
+* [*Breaking change:] Added specializations for `std::hash<boost::opitonal<T>>`. This fixes [@https://github.com/boostorg/optional/issues/55 issue #55]. You may get compiler errors when your program provides specializations for `std::hash<boost::optional<T>>`. If this happens, define macro `BOOST_OPTIONAL_CONFIG_DO_NOT_SPECIALIZE_STD_HASH` to suppress the specializations of `std::hash` in this library.
+
+[heading Boost Release 1.79]
+
+* Fixed [@https://github.com/boostorg/optional/issues/98 issue #98].
+* Fixed [@https://github.com/boostorg/optional/issues/92 issue #92].
+* Added support for `BOOST_NO_IOSTREAM`.
+* Now aligned storage uses `unsigned char` rather than `char` to avoid UB.
+* Now using cv-unqualified `value_type` with placement `new` to avoid UB.
+
+[heading Boost Release 1.76]
+
+* Fixed MSVC warning C4702.
+
 [heading Boost Release 1.75]
 
 * `boost::none` is `constexpr`-declared.

doc/html/boost_optional/acknowledgements.html

@@ -116,7 +116,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/boost_optional/dependencies_and_portability.html

@@ -77,7 +77,7 @@
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 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/boost_optional/dependencies_and_portability/emplace_operations_in_older_compilers.html

@@ -76,7 +76,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

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@@ -93,7 +93,7 @@
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 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/boost_optional/quick_start.html

@@ -155,7 +155,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/boost_optional/quick_start/bypassing_unnecessary_default_construction.html

@@ -61,7 +61,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/boost_optional/quick_start/optional_automatic_variables.html

@@ -61,7 +61,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/boost_optional/quick_start/optional_data_members.html

@@ -80,7 +80,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/boost_optional/quick_start/storage_in_containers.html

@@ -50,7 +50,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/boost_optional/reference/header__boost_optional_bad_optional_access_hpp_.html

@@ -49,7 +49,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/boost_optional/reference/header__boost_optional_bad_optional_access_hpp_/detailed_semantics.html

@@ -46,7 +46,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/boost_optional/reference/header__boost_optional_hpp_.html

@@ -33,7 +33,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/boost_optional/reference/header__boost_optional_optional_fwd_hpp_.html

@@ -52,7 +52,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/boost_optional/reference/header__boost_optional_optional_hpp_/detailed_semantics___free_functions.html

@@ -507,7 +507,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/boost_optional/reference/header__boost_optional_optional_hpp_/detailed_semantics___optional_references.html

@@ -538,7 +538,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/boost_optional/reference/header__boost_optional_optional_hpp_/detailed_semantics___optional_values.html

@@ -1774,7 +1774,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/boost_optional/reference/header__boost_optional_optional_hpp_/header_optional_in_place_init.html

@@ -47,7 +47,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/boost_optional/reference/header__boost_optional_optional_hpp_/header_optional_optional_refs.html

@@ -104,7 +104,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/boost_optional/reference/header__boost_optional_optional_hpp_/header_optional_optional_values.html

@@ -139,7 +139,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/boost_optional/reference/io_header.html

@@ -58,7 +58,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/boost_optional/reference/io_header/io_semantics.html

@@ -98,7 +98,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/boost_optional/relnotes.html

@@ -28,6 +28,42 @@
 </h2></div></div></div>
 <h4>
 <a name="boost_optional.relnotes.h0"></a>
+      <span class="phrase"><a name="boost_optional.relnotes.boost_release_1_79"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_79">Boost
+      Release 1.79</a>
+    </h4>
+<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
+<li class="listitem">
+          Fixed <a href="https://github.com/boostorg/optional/issues/98" target="_top">issue
+          #98</a>.
+        </li>
+<li class="listitem">
+          Fixed <a href="https://github.com/boostorg/optional/issues/92" target="_top">issue
+          #92</a>.
+        </li>
+<li class="listitem">
+          Added support for <code class="computeroutput"><span class="identifier">BOOST_NO_IOSTREAM</span></code>.
+        </li>
+<li class="listitem">
+          Now aligned storage uses <code class="computeroutput"><span class="keyword">unsigned</span>
+          <span class="keyword">char</span></code> rather than <code class="computeroutput"><span class="keyword">char</span></code>
+          to avoid UB.
+        </li>
+<li class="listitem">
+          Now using cv-unqualified <code class="computeroutput"><span class="identifier">value_type</span></code>
+          with placement <code class="computeroutput"><span class="keyword">new</span></code> to avoid
+          UB.
+        </li>
+</ul></div>
+<h4>
+<a name="boost_optional.relnotes.h1"></a>
+      <span class="phrase"><a name="boost_optional.relnotes.boost_release_1_76"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_76">Boost
+      Release 1.76</a>
+    </h4>
+<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
+          Fixed MSVC warning C4702.
+        </li></ul></div>
+<h4>
+<a name="boost_optional.relnotes.h2"></a>
       <span class="phrase"><a name="boost_optional.relnotes.boost_release_1_75"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_75">Boost
       Release 1.75</a>
     </h4>
@@ -41,7 +77,7 @@
         </li>
 </ul></div>
 <h4>
-<a name="boost_optional.relnotes.h1"></a>
+<a name="boost_optional.relnotes.h3"></a>
       <span class="phrase"><a name="boost_optional.relnotes.boost_release_1_73"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_73">Boost
       Release 1.73</a>
     </h4>
@@ -64,7 +100,7 @@
         </li>
 </ul></div>
 <h4>
-<a name="boost_optional.relnotes.h2"></a>
+<a name="boost_optional.relnotes.h4"></a>
       <span class="phrase"><a name="boost_optional.relnotes.boost_release_1_69"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_69">Boost
       Release 1.69</a>
     </h4>
@@ -82,7 +118,7 @@
         </li>
 </ul></div>
 <h4>
-<a name="boost_optional.relnotes.h3"></a>
+<a name="boost_optional.relnotes.h5"></a>
       <span class="phrase"><a name="boost_optional.relnotes.boost_release_1_68"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_68">Boost
       Release 1.68</a>
     </h4>
@@ -99,7 +135,7 @@
         </li>
 </ul></div>
 <h4>
-<a name="boost_optional.relnotes.h4"></a>
+<a name="boost_optional.relnotes.h6"></a>
       <span class="phrase"><a name="boost_optional.relnotes.boost_release_1_67"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_67">Boost
       Release 1.67</a>
     </h4>
@@ -113,7 +149,7 @@
         </li>
 </ul></div>
 <h4>
-<a name="boost_optional.relnotes.h5"></a>
+<a name="boost_optional.relnotes.h7"></a>
       <span class="phrase"><a name="boost_optional.relnotes.boost_release_1_66"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_66">Boost
       Release 1.66</a>
     </h4>
@@ -131,7 +167,7 @@
         </li>
 </ul></div>
 <h4>
-<a name="boost_optional.relnotes.h6"></a>
+<a name="boost_optional.relnotes.h8"></a>
       <span class="phrase"><a name="boost_optional.relnotes.boost_release_1_63"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_63">Boost
       Release 1.63</a>
     </h4>
@@ -155,7 +191,7 @@
         </li>
 </ul></div>
 <h4>
-<a name="boost_optional.relnotes.h7"></a>
+<a name="boost_optional.relnotes.h9"></a>
       <span class="phrase"><a name="boost_optional.relnotes.boost_release_1_62"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_62">Boost
       Release 1.62</a>
     </h4>
@@ -163,7 +199,7 @@
           Fixed <a href="https://svn.boost.org/trac/boost/ticket/12179" target="_top">Trac #12179</a>.
         </li></ul></div>
 <h4>
-<a name="boost_optional.relnotes.h8"></a>
+<a name="boost_optional.relnotes.h10"></a>
       <span class="phrase"><a name="boost_optional.relnotes.boost_release_1_61"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_61">Boost
       Release 1.61</a>
     </h4>
@@ -206,7 +242,7 @@
         </li>
 </ul></div>
 <h4>
-<a name="boost_optional.relnotes.h9"></a>
+<a name="boost_optional.relnotes.h11"></a>
       <span class="phrase"><a name="boost_optional.relnotes.boost_release_1_60"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_60">Boost
       Release 1.60</a>
     </h4>
@@ -217,7 +253,7 @@
           #11203</a>.
         </li></ul></div>
 <h4>
-<a name="boost_optional.relnotes.h10"></a>
+<a name="boost_optional.relnotes.h12"></a>
       <span class="phrase"><a name="boost_optional.relnotes.boost_release_1_59"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_59">Boost
       Release 1.59</a>
     </h4>
@@ -231,7 +267,7 @@
         </li>
 </ul></div>
 <h4>
-<a name="boost_optional.relnotes.h11"></a>
+<a name="boost_optional.relnotes.h13"></a>
       <span class="phrase"><a name="boost_optional.relnotes.boost_release_1_58"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_58">Boost
       Release 1.58</a>
     </h4>
@@ -267,7 +303,7 @@
         </li>
 </ul></div>
 <h4>
-<a name="boost_optional.relnotes.h12"></a>
+<a name="boost_optional.relnotes.h14"></a>
       <span class="phrase"><a name="boost_optional.relnotes.boost_release_1_57"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_57">Boost
       Release 1.57</a>
     </h4>
@@ -277,7 +313,7 @@
           to fix C++03 compile error on <code class="computeroutput"><span class="identifier">logic_error</span><span class="special">(</span><span class="string">"..."</span><span class="special">)</span></code>"</em></span>.
         </li></ul></div>
 <h4>
-<a name="boost_optional.relnotes.h13"></a>
+<a name="boost_optional.relnotes.h15"></a>
       <span class="phrase"><a name="boost_optional.relnotes.boost_release_1_56"></a></span><a class="link" href="relnotes.html#boost_optional.relnotes.boost_release_1_56">Boost
       Release 1.56</a>
     </h4>
@@ -334,7 +370,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/boost_optional/tutorial/design_overview.html

@@ -170,7 +170,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/boost_optional/tutorial/design_overview/the_interface.html

@@ -173,7 +173,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/boost_optional/tutorial/design_overview/the_semantics.html

@@ -107,7 +107,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/boost_optional/tutorial/exception_safety_guarantees.html

@@ -161,7 +161,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/boost_optional/tutorial/gotchas.html

@@ -98,7 +98,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/boost_optional/tutorial/gotchas/false_positive_with__wmaybe_uninitialized.html

@@ -63,7 +63,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/boost_optional/tutorial/gotchas/mixed_relational_comparisons.html

@@ -30,7 +30,7 @@
 <p>
           Because <code class="computeroutput"><span class="identifier">T</span></code> is convertible
           to <code class="computeroutput"><span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span></code>
-          and because <code class="computeroutput"><span class="identifier">opiotnal</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span></code>
+          and because <code class="computeroutput"><span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span></code>
           is <a href="http://www.sgi.com/tech/stl/LessThanComparable.html" target="_top"><code class="computeroutput"><span class="identifier">LessThanComparable</span></code></a> when <code class="computeroutput"><span class="identifier">T</span></code> is <a href="http://www.sgi.com/tech/stl/LessThanComparable.html" target="_top"><code class="computeroutput"><span class="identifier">LessThanComparable</span></code></a>, you can sometimes
           get an unexpected runtime result where you would rather expect a compiler
           error:
@@ -45,7 +45,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/boost_optional/tutorial/gotchas/moved_from__optional_.html

@@ -42,14 +42,14 @@
           Quite a lot of people expect that when an object that contains a value
           is moved from, its contained value should be destroyed. This is not so,
           for performance reasons. Current semantics allow the implementation of
-          <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">opiotnal</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span></code>
+          <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">optional</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;</span></code>
           to be trivially copyable when <code class="computeroutput"><span class="identifier">T</span></code>
           is trivial.
         </p>
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/boost_optional/tutorial/in_place_factories.html

@@ -183,7 +183,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/boost_optional/tutorial/io_operators.html

@@ -73,7 +73,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/boost_optional/tutorial/optional_references.html

@@ -103,7 +103,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/boost_optional/tutorial/optional_references/rebinding_semantics_for_assignment_of_optional_references.html

@@ -133,7 +133,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/boost_optional/tutorial/performance_considerations.html

@@ -251,7 +251,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/boost_optional/tutorial/relational_operators.html

@@ -99,7 +99,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/boost_optional/tutorial/type_requirements.html

@@ -95,7 +95,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/boost_optional/tutorial/when_to_use_optional.html

@@ -128,7 +128,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/index.html

@@ -26,7 +26,7 @@
 <span class="firstname">Fernando Luis</span> <span class="surname">Cacciola Carballal</span>
 </h3></div></div>
 <div><p class="copyright">Copyright © 2003-2007 Fernando Luis Cacciola Carballal</p></div>
-<div><p class="copyright">Copyright © 2014-2018 Andrzej Krzemieński</p></div>
+<div><p class="copyright">Copyright © 2014-2021 Andrzej Krzemieński</p></div>
 <div><div class="legalnotice">
 <a name="optional.legal"></a><p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
@@ -145,7 +145,7 @@
 </div>
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
-<td align="left"><p><small>Last revised: October 28, 2020 at 21:28:19 GMT</small></p></td>
+<td align="left"><p><small>Last revised: March 26, 2022 at 22:47:53 GMT</small></p></td>
 <td align="right"><div class="copyright-footer"></div></td>
 </tr></table>
 <hr>

doc/html/optional/reference.html

@@ -75,7 +75,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/optional/reference/header__boost_optional_optional_hpp_.html

@@ -97,7 +97,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

doc/html/optional/tutorial.html

@@ -139,7 +139,7 @@
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 <td align="left"></td>
-<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2018 Andrzej Krzemieński<p>
+<td align="right"><div class="copyright-footer">Copyright © 2003-2007 Fernando Luis Cacciola Carballal<br>Copyright © 2014-2021 Andrzej Krzemieński<p>
         Distributed under the Boost Software License, Version 1.0. (See accompanying
         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
       </p>

include/boost/optional/detail/optional_aligned_storage.hpp

@@ -28,7 +28,7 @@ class aligned_storage
     // BOOST_MAY_ALIAS works around GCC warnings about breaking strict aliasing rules when casting storage address to T*
     union BOOST_MAY_ALIAS dummy_u
     {
-        char data[ sizeof(T) ];
+        unsigned char data[ sizeof(T) ];
         BOOST_DEDUCED_TYPENAME type_with_alignment<
           ::boost::alignment_of<T>::value >::type aligner_;
     } dummy_ ;

include/boost/optional/detail/optional_hash.hpp

@@ -0,0 +1,49 @@
+// Copyright (C) 2022 Andrzej Krzemienski.
+//
+// Use, modification, and distribution is subject to the Boost Software
+// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
+// http://www.boost.org/LICENSE_1_0.txt)
+//
+// See http://www.boost.org/libs/optional for documentation.
+//
+// You are welcome to contact the author at:
+//  akrzemi1@gmail.com
+
+#ifndef BOOST_OPTIONAL_DETAIL_OPTIONAL_HASH_AJK_20MAY2022_HPP
+#define BOOST_OPTIONAL_DETAIL_OPTIONAL_HASH_AJK_20MAY2022_HPP
+
+#include <boost/optional/optional_fwd.hpp>
+#include <boost/config.hpp>
+
+#if !defined(BOOST_OPTIONAL_CONFIG_DO_NOT_SPECIALIZE_STD_HASH) && !defined(BOOST_NO_CXX11_HDR_FUNCTIONAL)
+
+#include <functional>
+
+namespace std
+{
+  template <typename T>
+  struct hash<boost::optional<T> >
+  {
+    typedef std::size_t result_type;
+    typedef boost::optional<T> argument_type;
+
+    BOOST_CONSTEXPR result_type operator()(const argument_type& arg) const {
+      return arg ? std::hash<T>()(*arg) : result_type();
+    }
+  };
+
+  template <typename T>
+  struct hash<boost::optional<T&> >
+  {
+    typedef std::size_t result_type;
+    typedef boost::optional<T&> argument_type;
+
+    BOOST_CONSTEXPR result_type operator()(const argument_type& arg) const {
+      return arg ? std::hash<T>()(*arg) : result_type();
+    }
+  };
+}
+
+#endif // !defined(BOOST_OPTIONAL_CONFIG_DO_NOT_SPECIALIZE_STD_HASH) && !defined(BOOST_NO_CXX11_HDR_FUNCTIONAL)
+
+#endif // header guard

include/boost/optional/detail/optional_reference_spec.hpp

@@ -151,7 +151,14 @@ public:
     T* get_ptr() const BOOST_NOEXCEPT { return ptr_; }
     T* operator->() const { BOOST_ASSERT(ptr_); return ptr_; }
     T& operator*() const { BOOST_ASSERT(ptr_); return *ptr_; }
-    T& value() const { return ptr_ ? *ptr_ : (throw_exception(bad_optional_access()), *ptr_); }
+    
+    T& value() const
+    {
+      if (this->is_initialized())
+        return this->get();
+      else
+        throw_exception(bad_optional_access());
+    }
     
     bool operator!() const BOOST_NOEXCEPT { return ptr_ == 0; }  
     BOOST_EXPLICIT_OPERATOR_BOOL_NOEXCEPT()

include/boost/optional/detail/optional_trivially_copyable_base.hpp

@@ -1,3 +1,14 @@
+// Copyright (C) 2017 Andrzej Krzemienski.
+//
+// Use, modification, and distribution is subject to the Boost Software
+// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
+// http://www.boost.org/LICENSE_1_0.txt)
+//
+// See http://www.boost.org/libs/optional for documentation.
+//
+// You are welcome to contact the author at:
+//  akrzemi1@gmail.com
+
 // trivilally-copyable version of the storage
 
 template<class T>
@@ -69,7 +80,7 @@ class tc_optional_base : public optional_tag
     // ~tc_optional_base() = default;
 
     // Assigns from another optional<T> (deep-copies the rhs value)
-    void assign ( tc_optional_base const& rhs ) 
+    void assign ( tc_optional_base const& rhs )
     {
       *this = rhs;
     }
@@ -84,7 +95,7 @@ class tc_optional_base : public optional_tag
 #else
         m_storage = static_cast<value_type>(rhs.get());
 #endif
-          
+
       m_initialized = rhs.is_initialized();
     }
 
@@ -99,7 +110,7 @@ class tc_optional_base : public optional_tag
       m_initialized = rhs.is_initialized();
     }
 #endif
-    
+
     void assign ( argument_type val )
     {
       construct(val);
@@ -166,7 +177,7 @@ class tc_optional_base : public optional_tag
     {
       construct(in_place_init, boost::forward<Args>(args)...);
     }
-     
+
     template<class... Args>
     explicit tc_optional_base ( in_place_init_t, Args&&... args )
       :
@@ -174,7 +185,7 @@ class tc_optional_base : public optional_tag
     {
       construct(in_place_init, boost::forward<Args>(args)...);
     }
-    
+
     template<class... Args>
     explicit tc_optional_base ( in_place_init_if_t, bool cond, Args&&... args )
       :
@@ -190,24 +201,24 @@ class tc_optional_base : public optional_tag
        m_storage = value_type( boost::forward<Arg>(arg) );
        m_initialized = true ;
      }
-     
+
     void construct ( in_place_init_t )
      {
        m_storage = value_type();
        m_initialized = true ;
      }
-     
+
     template<class Arg>
     void emplace_assign ( Arg&& arg )
      {
        construct(in_place_init, boost::forward<Arg>(arg)) ;
      }
-     
+
     void emplace_assign ()
      {
        construct(in_place_init) ;
      }
-     
+
     template<class Arg>
     explicit tc_optional_base ( in_place_init_t, Arg&& arg )
       :
@@ -215,11 +226,11 @@ class tc_optional_base : public optional_tag
     {
       construct(in_place_init, boost::forward<Arg>(arg));
     }
-    
+
     explicit tc_optional_base ( in_place_init_t )
       :
       m_initialized(false), m_storage() {}
-    
+
     template<class Arg>
     explicit tc_optional_base ( in_place_init_if_t, bool cond, Arg&& arg )
       :
@@ -228,7 +239,7 @@ class tc_optional_base : public optional_tag
       if ( cond )
         construct(in_place_init, boost::forward<Arg>(arg));
     }
-    
+
     explicit tc_optional_base ( in_place_init_if_t, bool cond )
       :
       m_initialized(false)
@@ -238,21 +249,21 @@ class tc_optional_base : public optional_tag
     }
 
 #else
-     
+
     template<class Arg>
     void construct ( in_place_init_t, const Arg& arg )
      {
        m_storage = value_type( arg );
        m_initialized = true ;
      }
-     
+
     template<class Arg>
     void construct ( in_place_init_t, Arg& arg )
      {
        m_storage = value_type( arg );
        m_initialized = true ;
      }
-     
+
     void construct ( in_place_init_t )
      {
        m_storage = value_type();
@@ -264,18 +275,18 @@ class tc_optional_base : public optional_tag
     {
       construct(in_place_init, arg);
     }
-     
+
     template<class Arg>
     void emplace_assign ( Arg& arg )
     {
       construct(in_place_init, arg);
     }
-     
+
     void emplace_assign ()
     {
       construct(in_place_init);
     }
-    
+
     template<class Arg>
     explicit tc_optional_base ( in_place_init_t, const Arg& arg )
       : m_initialized(false)
@@ -289,13 +300,13 @@ class tc_optional_base : public optional_tag
     {
       construct(in_place_init, arg);
     }
-    
+
     explicit tc_optional_base ( in_place_init_t )
       : m_initialized(false)
     {
       construct(in_place_init);
     }
-    
+
     template<class Arg>
     explicit tc_optional_base ( in_place_init_if_t, bool cond, const Arg& arg )
       : m_initialized(false)
@@ -303,15 +314,15 @@ class tc_optional_base : public optional_tag
       if ( cond )
         construct(in_place_init, arg);
     }
-    
+
     template<class Arg>
     explicit tc_optional_base ( in_place_init_if_t, bool cond, Arg& arg )
       : m_initialized(false)
     {
       if ( cond )
         construct(in_place_init, arg);
-    } 
-    
+    }
+
     explicit tc_optional_base ( in_place_init_if_t, bool cond )
       : m_initialized(false)
     {

include/boost/optional/optional.hpp

@@ -1,5 +1,5 @@
 // Copyright (C) 2003, 2008 Fernando Luis Cacciola Carballal.
-// Copyright (C) 2014 - 2018 Andrzej Krzemienski.
+// Copyright (C) 2014 - 2021 Andrzej Krzemienski.
 //
 // Use, modification, and distribution is subject to the Boost Software
 // License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
@@ -18,7 +18,9 @@
 #define BOOST_OPTIONAL_OPTIONAL_FLC_19NOV2002_HPP
 
 #include <new>
+#ifndef BOOST_NO_IOSTREAM
 #include <iosfwd>
+#endif // BOOST_NO_IOSTREAM
 
 #ifdef BOOST_OPTIONAL_DETAIL_USE_STD_TYPE_TRAITS
 #  include <type_traits>
@@ -35,14 +37,18 @@
 #include <boost/type.hpp>
 #include <boost/type_traits/alignment_of.hpp>
 #include <boost/type_traits/conditional.hpp>
+#include <boost/type_traits/conjunction.hpp>
+#include <boost/type_traits/disjunction.hpp>
 #include <boost/type_traits/has_nothrow_constructor.hpp>
 #include <boost/type_traits/type_with_alignment.hpp>
 #include <boost/type_traits/remove_const.hpp>
 #include <boost/type_traits/remove_reference.hpp>
 #include <boost/type_traits/decay.hpp>
+#include <boost/type_traits/is_assignable.hpp>
 #include <boost/type_traits/is_base_of.hpp>
 #include <boost/type_traits/is_const.hpp>
 #include <boost/type_traits/is_constructible.hpp>
+#include <boost/type_traits/is_convertible.hpp>
 #include <boost/type_traits/is_lvalue_reference.hpp>
 #include <boost/type_traits/is_nothrow_move_assignable.hpp>
 #include <boost/type_traits/is_nothrow_move_constructible.hpp>
@@ -59,6 +65,7 @@
 #include <boost/optional/detail/optional_config.hpp>
 #include <boost/optional/detail/optional_factory_support.hpp>
 #include <boost/optional/detail/optional_aligned_storage.hpp>
+#include <boost/optional/detail/optional_hash.hpp>
 
 namespace boost { namespace optional_detail {
 
@@ -123,6 +130,7 @@ class optional_base : public optional_tag
   protected :
 
     typedef T value_type ;
+    typedef typename boost::remove_const<T>::type unqualified_value_type;
 
   protected:
     typedef T &       reference_type ;
@@ -399,14 +407,14 @@ class optional_base : public optional_tag
 
     void construct ( argument_type val )
      {
-       ::new (m_storage.address()) value_type(val) ;
+       ::new (m_storage.address()) unqualified_value_type(val) ;
        m_initialized = true ;
      }
 
 #ifndef  BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES
     void construct ( rval_reference_type val )
      {
-       ::new (m_storage.address()) value_type( boost::move(val) ) ;
+       ::new (m_storage.address()) unqualified_value_type( boost::move(val) ) ;
        m_initialized = true ;
      }
 #endif
@@ -418,7 +426,7 @@ class optional_base : public optional_tag
     template<class... Args>
     void construct ( in_place_init_t, Args&&... args )
     {
-      ::new (m_storage.address()) value_type( boost::forward<Args>(args)... ) ;
+      ::new (m_storage.address()) unqualified_value_type( boost::forward<Args>(args)... ) ;
       m_initialized = true ;
     }
 
@@ -449,13 +457,13 @@ class optional_base : public optional_tag
     template<class Arg>
     void construct ( in_place_init_t, Arg&& arg )
      {
-       ::new (m_storage.address()) value_type( boost::forward<Arg>(arg) );
+       ::new (m_storage.address()) unqualified_value_type( boost::forward<Arg>(arg) );
        m_initialized = true ;
      }
 
     void construct ( in_place_init_t )
      {
-       ::new (m_storage.address()) value_type();
+       ::new (m_storage.address()) unqualified_value_type();
        m_initialized = true ;
      }
 
@@ -509,20 +517,20 @@ class optional_base : public optional_tag
     template<class Arg>
     void construct ( in_place_init_t, const Arg& arg )
      {
-       ::new (m_storage.address()) value_type( arg );
+       ::new (m_storage.address()) unqualified_value_type( arg );
        m_initialized = true ;
      }
 
     template<class Arg>
     void construct ( in_place_init_t, Arg& arg )
      {
-       ::new (m_storage.address()) value_type( arg );
+       ::new (m_storage.address()) unqualified_value_type( arg );
        m_initialized = true ;
      }
 
     void construct ( in_place_init_t )
      {
-       ::new (m_storage.address()) value_type();
+       ::new (m_storage.address()) unqualified_value_type();
        m_initialized = true ;
      }
 
@@ -667,7 +675,7 @@ class optional_base : public optional_tag
     template<class Expr>
     void construct ( Expr&& expr, void const* )
     {
-      new (m_storage.address()) value_type(boost::forward<Expr>(expr)) ;
+      new (m_storage.address()) unqualified_value_type(boost::forward<Expr>(expr)) ;
       m_initialized = true ;
     }
 
@@ -688,7 +696,7 @@ class optional_base : public optional_tag
     template<class Expr>
     void construct ( Expr const& expr, void const* )
      {
-       new (m_storage.address()) value_type(expr) ;
+       new (m_storage.address()) unqualified_value_type(expr) ;
        m_initialized = true ;
      }
 
@@ -726,7 +734,7 @@ class optional_base : public optional_tag
        {
          // An exception can be thrown here.
          // It it happens, THIS will be left uninitialized.
-         new (m_storage.address()) value_type(boost::move(expr.get())) ;
+         new (m_storage.address()) unqualified_value_type(boost::move(expr.get())) ;
          m_initialized = true ;
        }
      }
@@ -739,7 +747,7 @@ class optional_base : public optional_tag
        {
          // An exception can be thrown here.
          // It it happens, THIS will be left uninitialized.
-         new (m_storage.address()) value_type(expr.get()) ;
+         new (m_storage.address()) unqualified_value_type(expr.get()) ;
          m_initialized = true ;
        }
      }
@@ -779,7 +787,7 @@ class optional_base : public optional_tag
 
 // definition of metafunction is_optional_val_init_candidate
 template <typename U>
-struct is_optional_related
+struct is_optional_or_tag
   : boost::conditional< boost::is_base_of<optional_detail::optional_tag, BOOST_DEDUCED_TYPENAME boost::decay<U>::type>::value
                      || boost::is_same<BOOST_DEDUCED_TYPENAME boost::decay<U>::type, none_t>::value
                      || boost::is_same<BOOST_DEDUCED_TYPENAME boost::decay<U>::type, in_place_init_t>::value
@@ -787,14 +795,22 @@ struct is_optional_related
     boost::true_type, boost::false_type>::type
 {};
 
+template <typename T, typename U>
+struct has_dedicated_constructor
+  : boost::disjunction<is_optional_or_tag<U>, boost::is_same<T, BOOST_DEDUCED_TYPENAME boost::decay<U>::type> >
+{};
+
+template <typename U>
+struct is_in_place_factory
+  : boost::disjunction< boost::is_base_of<boost::in_place_factory_base, BOOST_DEDUCED_TYPENAME boost::decay<U>::type>,
+                        boost::is_base_of<boost::typed_in_place_factory_base, BOOST_DEDUCED_TYPENAME boost::decay<U>::type> >
+{};
+
 #if !defined(BOOST_OPTIONAL_DETAIL_NO_IS_CONSTRUCTIBLE_TRAIT)
 
 template <typename T, typename U>
-struct is_convertible_to_T_or_factory
-  : boost::conditional< boost::is_base_of<boost::in_place_factory_base, BOOST_DEDUCED_TYPENAME boost::decay<U>::type>::value
-                     || boost::is_base_of<boost::typed_in_place_factory_base, BOOST_DEDUCED_TYPENAME boost::decay<U>::type>::value
-                     || (boost::is_constructible<T, U&&>::value && !boost::is_same<T, BOOST_DEDUCED_TYPENAME boost::decay<U>::type>::value)
-                      , boost::true_type, boost::false_type>::type
+struct is_factory_or_constructible_to_T
+  : boost::disjunction< is_in_place_factory<U>, boost::is_constructible<T, U&&> >
 {};
 
 template <typename T, typename U>
@@ -804,7 +820,7 @@ struct is_optional_constructible : boost::is_constructible<T, U>
 #else
 
 template <typename, typename>
-struct is_convertible_to_T_or_factory : boost::true_type
+struct is_factory_or_constructible_to_T : boost::true_type
 {};
 
 template <typename T, typename U>
@@ -813,15 +829,58 @@ struct is_optional_constructible : boost::true_type
 
 #endif // is_convertible condition
 
-template <typename T, typename U, bool = is_optional_related<U>::value>
+#if !defined(BOOST_NO_CXX11_DECLTYPE) && !BOOST_WORKAROUND(BOOST_MSVC, < 1800)
+// for is_assignable
+
+#if (!defined BOOST_NO_CXX11_RVALUE_REFERENCES)
+// On some initial rvalue reference implementations GCC does it in a strange way,
+// preferring perfect-forwarding constructor to implicit copy constructor.
+
+template <typename T, typename U>
+struct is_opt_assignable
+  : boost::conjunction<boost::is_convertible<U&&, T>, boost::is_assignable<T&, U&&> >
+{};
+
+#else
+
+template <typename T, typename U>
+struct is_opt_assignable
+  : boost::conjunction<boost::is_convertible<U, T>, boost::is_assignable<T&, U> >
+{};
+
+#endif
+
+#else
+
+template <typename T, typename U>
+struct is_opt_assignable : boost::is_convertible<U, T>
+{};
+
+#endif
+
+template <typename T, typename U>
+struct is_factory_or_opt_assignable_to_T
+  : boost::disjunction< is_in_place_factory<U>, is_opt_assignable<T, U> >
+{};
+
+template <typename T, typename U, bool = has_dedicated_constructor<T, U>::value>
 struct is_optional_val_init_candidate
   : boost::false_type
 {};
 
 template <typename T, typename U>
 struct is_optional_val_init_candidate<T, U, false>
-  : boost::conditional< is_convertible_to_T_or_factory<T, U>::value
-                      , boost::true_type, boost::false_type>::type
+  : is_factory_or_constructible_to_T<T, U>
+{};
+
+template <typename T, typename U, bool = has_dedicated_constructor<T, U>::value>
+struct is_optional_val_assign_candidate
+  : boost::false_type
+{};
+
+template <typename T, typename U>
+struct is_optional_val_assign_candidate<T, U, false>
+  : is_factory_or_opt_assignable_to_T<T, U>
 {};
 
 } // namespace optional_detail
@@ -994,7 +1053,7 @@ class optional
 #ifndef  BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES
 
     template<class Expr>
-    BOOST_DEDUCED_TYPENAME boost::enable_if<optional_detail::is_optional_val_init_candidate<T, Expr>, optional&>::type
+    BOOST_DEDUCED_TYPENAME boost::enable_if<optional_detail::is_optional_val_assign_candidate<T, Expr>, optional&>::type
     operator= ( Expr&& expr )
       {
         this->assign_expr(boost::forward<Expr>(expr),boost::addressof(expr));
@@ -1586,6 +1645,7 @@ get_pointer ( optional<T>& opt )
 
 } // namespace boost
 
+#ifndef BOOST_NO_IOSTREAM
 namespace boost {
 
 // The following declaration prevents a bug where operator safe-bool is used upon streaming optional object if you forget the IO header.
@@ -1598,6 +1658,7 @@ operator<<(std::basic_ostream<CharType, CharTrait>& os, optional_detail::optiona
 }
 
 } // namespace boost
+#endif // BOOST_NO_IOSTREAM
 
 #include <boost/optional/detail/optional_relops.hpp>
 #include <boost/optional/detail/optional_swap.hpp>

include/boost/optional/optional_io.hpp

@@ -12,6 +12,7 @@
 #ifndef BOOST_OPTIONAL_OPTIONAL_IO_FLC_19NOV2002_HPP
 #define BOOST_OPTIONAL_OPTIONAL_IO_FLC_19NOV2002_HPP
 
+#ifndef BOOST_NO_IOSTREAM
 #include <istream>
 #include <ostream>
 
@@ -31,7 +32,7 @@ operator<<(std::basic_ostream<CharType, CharTrait>& out, none_t)
   {
     out << "--";
   }
-   
+
   return out;
 }
 
@@ -90,5 +91,5 @@ operator>>(std::basic_istream<CharType, CharTrait>& in, optional<T>& v)
 
 } // namespace boost
 
+#endif // BOOST_NO_IOSTREAM
 #endif
-

meta/libraries.json

@@ -12,5 +12,6 @@
     "maintainers": [
         "Fernando Cacciola <fernando_cacciola -at- ciudad.com.ar>",
         "Andrzej Krzemienski <akrzemi1 -at- gmail.com>"
-    ]
+    ],
+    "cxxstd": "03"
 }

test/Jamfile.v2

@@ -22,9 +22,11 @@ import testing ;
     [ run optional_test_swap.cpp ]
     [ run optional_test_conversions_from_U.cpp ]
     [ run optional_test_convert_from_T.cpp ]
+    [ run optional_test_convert_assign.cpp ]
     [ run optional_test_empty_braces.cpp ]
     [ run optional_test_make_optional.cpp ]
     [ run optional_test_flat_map.cpp ]
+    [ run optional_test_hash.cpp ]
     [ run optional_test_map.cpp ]
     [ run optional_test_tie.cpp ]
     [ run optional_test_ref_assign_portable_minimum.cpp ]

test/optional_test.cpp

@@ -12,7 +12,9 @@
 // Revisions:
 // 12 May 2008 (added more swap tests)
 //
+#ifndef BOOST_NO_IOSTREAM
 #include<iostream>
+#endif // BOOST_NO_IOSTREAM
 #include<stdexcept>
 #include<string>
 
@@ -908,7 +910,7 @@ void test_no_implicit_conversions()
 
 
 // Test for support for classes with overridden operator&
-class CustomAddressOfClass  
+class CustomAddressOfClass
 {
     int n;
 
@@ -950,5 +952,3 @@ int main()
 
   return boost::report_errors();
 }
-
-

test/optional_test_convert_assign.cpp

@@ -0,0 +1,57 @@
+// Copyright (C) 2021 Andrzej Krzemienski.
+//
+// Use, modification, and distribution is subject to the Boost Software
+// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
+// http://www.boost.org/LICENSE_1_0.txt)
+//
+// See http://www.boost.org/lib/optional for documentation.
+//
+// You are welcome to contact the author at:
+//  akrzemi1@gmail.com
+
+#include "boost/optional/optional.hpp"
+
+#include "boost/core/lightweight_test.hpp"
+#include "boost/none.hpp"
+
+//#ifndef BOOST_OPTIONAL_NO_CONVERTING_COPY_CTOR
+
+using boost::optional;
+
+struct implicit_bool_conv
+{
+  operator bool() const { return false; }
+};
+
+struct explicit_bool_conv
+{
+  bool operator!() const BOOST_NOEXCEPT { return false; }
+  BOOST_EXPLICIT_OPERATOR_BOOL_NOEXCEPT()
+};
+
+template <typename To, typename From>
+void test_convert_assign()
+{
+  optional<To> oi;
+  oi = From();
+  BOOST_TEST(oi);
+}
+
+void test_no_bad_assignment()
+{
+#if !defined(BOOST_NO_CXX11_DECLTYPE) && !BOOST_WORKAROUND(BOOST_MSVC, < 1800)
+  // this means that type trait `boost::is_assignable` works.
+  BOOST_STATIC_ASSERT((boost::is_assignable<optional<bool>&, bool>::value));
+  BOOST_STATIC_ASSERT((boost::is_assignable<optional<bool>&, implicit_bool_conv>::value));
+  BOOST_STATIC_ASSERT((! boost::is_assignable<optional<bool>&, explicit_bool_conv>::value));
+#endif
+}
+
+int main()
+{
+  test_convert_assign<int, short>();
+  test_convert_assign<bool, implicit_bool_conv>();
+  test_no_bad_assignment();
+
+  return boost::report_errors();
+}

test/optional_test_hash.cpp

@@ -0,0 +1,64 @@
+// Copyright (C) 2014 Andrzej Krzemienski.
+//
+// Use, modification, and distribution is subject to the Boost Software
+// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
+// http://www.boost.org/LICENSE_1_0.txt)
+//
+// See http://www.boost.org/lib/optional for documentation.
+//
+// You are welcome to contact the author at:
+//  akrzemi1@gmail.com
+
+#include "boost/optional/optional.hpp"
+#include "boost/config.hpp"
+#include "boost/core/lightweight_test.hpp"
+
+#if !defined(BOOST_NO_CXX11_HDR_UNORDERED_SET) && !defined(BOOST_OPTIONAL_CONFIG_DO_NOT_SPECIALIZE_STD_HASH)
+
+#include <unordered_set>
+
+void test_unordered_map()
+{
+  std::unordered_set<boost::optional<int> > set;
+  set.insert(boost::optional<int>(1));
+  set.insert(boost::optional<int>(1));
+
+
+  BOOST_TEST(set.size() == 1u);
+  BOOST_TEST(set.find(boost::optional<int>(1)) != set.end());
+}
+
+#else
+
+void test_unordered_map()
+{}
+
+#endif
+
+
+#if !defined(BOOST_OPTIONAL_CONFIG_DO_NOT_SPECIALIZE_STD_HASH) && !defined(BOOST_NO_CXX11_HDR_FUNCTIONAL)
+
+void tets_hash()
+{
+  std::hash<boost::optional<int> > hash_int;
+  boost::optional<int> oN;
+  boost::optional<int> o1(1);
+
+  BOOST_TEST(hash_int(oN) == hash_int(oN));
+  BOOST_TEST(hash_int(o1) == hash_int(o1));
+}
+
+#else
+
+void tets_hash()
+{}
+
+#endif
+
+
+int main()
+{
+  test_unordered_map();
+  tets_hash();
+  return boost::report_errors();
+}

test/optional_test_io.cpp

@@ -10,15 +10,19 @@
 // You are welcome to contact the author at:
 //  fernando_cacciola@hotmail.com
 
-#include <sstream>
 #include "boost/optional/optional.hpp"
 #include "boost/optional/optional_io.hpp"
+#include "boost/core/lightweight_test.hpp"
+
+#ifndef BOOST_NO_IOSTREAM
+
+#include <sstream>
 
 #ifdef BOOST_BORLANDC
 #pragma hdrstop
 #endif
 
-#include "boost/core/lightweight_test.hpp"
+
 
 using boost::optional;
 
@@ -29,7 +33,7 @@ void test2( Opt o, Opt buff )
 
   const int markv = 123 ;
   int mark = 0 ;
-  
+
   s << o << " " << markv ;
   s >> buff >> mark ;
 
@@ -85,3 +89,12 @@ int main()
 
   return boost::report_errors();
 }
+
+#else // BOOST_NO_IOSTREAM
+
+int main()
+{
+  return boost::report_errors();
+}
+
+#endif // BOOST_NO_IOSTREAM