Removed macos-13 GitHub Actions CI job.

The macos-13 image is deprecated by GitHub Actions and will be removed.

Refs https://github.com/actions/runner-images/issues/13046.

.github/workflows/ci.yml

@@ -33,18 +33,6 @@ jobs:
       matrix:
         include:
           # Linux, gcc
-          - toolset: gcc-4.8
-            cxxstd: "11"
-            os: ubuntu-latest
-            container: ubuntu:18.04
-            install:
-              - g++-4.8
-          - toolset: gcc-4.9
-            cxxstd: "11"
-            os: ubuntu-latest
-            container: ubuntu:16.04
-            install:
-              - g++-4.9
           - toolset: gcc-5
             cxxstd: "11,14,1z"
             os: ubuntu-latest
@@ -71,12 +59,14 @@ jobs:
               - g++-8
           - toolset: gcc-9
             cxxstd: "11,14,17,2a"
-            os: ubuntu-20.04
+            os: ubuntu-latest
+            container: ubuntu:20.04
             install:
               - g++-9
           - toolset: gcc-10
             cxxstd: "11,14,17,20"
-            os: ubuntu-20.04
+            os: ubuntu-latest
+            container: ubuntu:20.04
             install:
               - g++-10
           - toolset: gcc-11
@@ -99,6 +89,12 @@ jobs:
             os: ubuntu-24.04
             install:
               - g++-14
+          - toolset: gcc-15
+            cxxstd: "11,14,17,20,23,26"
+            os: ubuntu-latest
+            container: ubuntu:25.04
+            install:
+              - g++-15
           - name: UBSAN
             toolset: gcc-13
             cxxstd: "11,14,17,20,23"
@@ -185,13 +181,15 @@ jobs:
           - toolset: clang
             compiler: clang++-9
             cxxstd: "11,14,17,2a"
-            os: ubuntu-20.04
+            os: ubuntu-latest
+            container: ubuntu:20.04
             install:
               - clang-9
           - toolset: clang
             compiler: clang++-10
             cxxstd: "11,14,17,20"
-            os: ubuntu-20.04
+            os: ubuntu-latest
+            container: ubuntu:20.04
             install:
               - clang-10
           - toolset: clang
@@ -263,22 +261,22 @@ jobs:
             os: ubuntu-24.04
             install:
               - clang-19
-            sources:
-              - "deb http://apt.llvm.org/noble/ llvm-toolchain-noble-19 main"
-            source_keys:
-              - "https://apt.llvm.org/llvm-snapshot.gpg.key"
           - toolset: clang
-            compiler: clang++-19
+            compiler: clang++-20
             cxxstd: "11,14,17,20,23,26"
-            os: ubuntu-24.04
+            os: ubuntu-latest
+            container: ubuntu:25.04
             install:
-              - clang-19
-              - libc++-19-dev
-              - libc++abi-19-dev
-            sources:
-              - "deb http://apt.llvm.org/noble/ llvm-toolchain-noble-19 main"
-            source_keys:
-              - "https://apt.llvm.org/llvm-snapshot.gpg.key"
+              - clang-20
+          - toolset: clang
+            compiler: clang++-20
+            cxxstd: "11,14,17,20,23,26"
+            os: ubuntu-latest
+            container: ubuntu:25.04
+            install:
+              - clang-20
+              - libc++-20-dev
+              - libc++abi-20-dev
             cxxflags: -stdlib=libc++
             linkflags: -stdlib=libc++
           - name: UBSAN
@@ -295,9 +293,6 @@ jobs:
               - libc++-18-dev
               - libc++abi-18-dev
 
-          - toolset: clang
-            cxxstd: "11,14,17,20,2b"
-            os: macos-13
           - toolset: clang
             cxxstd: "11,14,17,20,2b"
             os: macos-14
@@ -307,7 +302,7 @@ jobs:
 
           - name: CMake tests
             cmake_tests: 1
-            os: ubuntu-20.04
+            os: ubuntu-24.04
 
     timeout-minutes: 20
     runs-on: ${{matrix.os}}
@@ -326,6 +321,22 @@ jobs:
                 echo "GHA_CONTAINER=${{matrix.container}}" >> $GITHUB_ENV
                 if [ -f "/etc/debian_version" ]
                 then
+                    # Use Azure APT mirrors in containers to avoid HTTP errors due to DDoS filters triggered by lots of CI jobs launching concurrently.
+                    # Note that not all Ubuntu versions support "mirror+file:..." URIs in APT sources, so just use Azure mirrors exclusively.
+                    # Note also that on recent Ubuntu versions DEB822 format is used for source files.
+                    APT_SOURCES=()
+                    if [ -d "/etc/apt/sources.list.d" ]
+                    then
+                        readarray -t APT_SOURCES < <(find "/etc/apt/sources.list.d" -type f -name '*.sources' -print)
+                    fi
+                    if [ -f "/etc/apt/sources.list" ]
+                    then
+                        APT_SOURCES+=("/etc/apt/sources.list")
+                    fi
+                    if [ "${#APT_SOURCES[@]}" -gt 0 ]
+                    then
+                        sed -i -E -e 's!([^ ]+) (http|https)://(archive|security)\.ubuntu\.com/ubuntu[^ ]*(.*)!\1 http://azure.archive.ubuntu.com/ubuntu/\4!' "${APT_SOURCES[@]}"
+                    fi
                     apt-get -o Acquire::Retries=$NET_RETRY_COUNT update
                     if [ "$(apt-cache search "^python-is-python3$" | wc -l)" -ne 0 ]
                     then
@@ -545,14 +556,6 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          - toolset: msvc-14.0
-            cxxstd: "14"
-            addrmd: 32,64
-            os: windows-2019
-          - toolset: msvc-14.2
-            cxxstd: "14,17,20,latest"
-            addrmd: 32,64
-            os: windows-2019
           - toolset: msvc-14.3
             cxxstd: "14,17,20,latest"
             addrmd: 32,64
@@ -562,9 +565,9 @@ jobs:
             addrmd: 32,64
             os: windows-2022
           - toolset: gcc
-            cxxstd: "11,14,17,2a"
+            cxxstd: "11,14,17,20,23"
             addrmd: 64
-            os: windows-2019
+            os: windows-2022
 
     timeout-minutes: 20
     runs-on: ${{matrix.os}}

README.md

@@ -19,8 +19,8 @@ Boost.Iterator, part of collection of the [Boost C++ Libraries](https://github.c
 
 Branch          | GitHub Actions | AppVeyor | Test Matrix | Dependencies |
 :-------------: | -------------- | -------- | ----------- | ------------ |
-[`master`](https://github.com/boostorg/iterator/tree/master) | [![GitHub Actions](https://github.com/boostorg/iterator/actions/workflows/ci.yml/badge.svg?branch=master)](https://github.com/boostorg/iterator/actions?query=branch%3Amaster) | [![AppVeyor](https://ci.appveyor.com/api/projects/status/ud8ug5aai8vd30hg/branch/master?svg=true)](https://ci.appveyor.com/project/Lastique/iterator/branch/master) | [![Tests](https://img.shields.io/badge/matrix-master-brightgreen.svg)](http://www.boost.org/development/tests/master/developer/iterator.html) | [![Dependencies](https://img.shields.io/badge/deps-master-brightgreen.svg)](https://pdimov.github.io/boostdep-report/master/iterator.html)
-[`develop`](https://github.com/boostorg/iterator/tree/develop) | [![GitHub Actions](https://github.com/boostorg/iterator/actions/workflows/ci.yml/badge.svg?branch=develop)](https://github.com/boostorg/iterator/actions?query=branch%3Adevelop) | [![AppVeyor](https://ci.appveyor.com/api/projects/status/ud8ug5aai8vd30hg/branch/develop?svg=true)](https://ci.appveyor.com/project/Lastique/iterator/branch/develop) | [![Tests](https://img.shields.io/badge/matrix-develop-brightgreen.svg)](http://www.boost.org/development/tests/develop/developer/iterator.html) | [![Dependencies](https://img.shields.io/badge/deps-develop-brightgreen.svg)](https://pdimov.github.io/boostdep-report/develop/iterator.html)
+[`master`](https://github.com/boostorg/iterator/tree/master) | [![GitHub Actions](https://github.com/boostorg/iterator/actions/workflows/ci.yml/badge.svg?branch=master)](https://github.com/boostorg/iterator/actions?query=branch%3Amaster) | [![AppVeyor](https://ci.appveyor.com/api/projects/status/ud8ug5aai8vd30hg/branch/master?svg=true)](https://ci.appveyor.com/project/Lastique/iterator/branch/master) | [![Tests](https://img.shields.io/badge/matrix-master-brightgreen.svg)](https://regression.boost.io/master/developer/iterator.html) | [![Dependencies](https://img.shields.io/badge/deps-master-brightgreen.svg)](https://pdimov.github.io/boostdep-report/master/iterator.html)
+[`develop`](https://github.com/boostorg/iterator/tree/develop) | [![GitHub Actions](https://github.com/boostorg/iterator/actions/workflows/ci.yml/badge.svg?branch=develop)](https://github.com/boostorg/iterator/actions?query=branch%3Adevelop) | [![AppVeyor](https://ci.appveyor.com/api/projects/status/ud8ug5aai8vd30hg/branch/develop?svg=true)](https://ci.appveyor.com/project/Lastique/iterator/branch/develop) | [![Tests](https://img.shields.io/badge/matrix-develop-brightgreen.svg)](https://regression.boost.io/develop/developer/iterator.html) | [![Dependencies](https://img.shields.io/badge/deps-develop-brightgreen.svg)](https://pdimov.github.io/boostdep-report/develop/iterator.html)
 
 ### License
 

appveyor.yml

@@ -32,9 +32,15 @@ environment:
       CXXSTD: 14,17,20,latest
       APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2022
     - TOOLSET: clang-win
-      ADDRMD: 32,64
+      ADDRMD: 32
       CXXSTD: 14,17,latest
-      APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2017
+      ENV_SCRIPT: C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\VC\Auxiliary\Build\vcvars32.bat
+      APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2019
+    - TOOLSET: clang-win
+      ADDRMD: 64
+      CXXSTD: 14,17,latest
+      ENV_SCRIPT: C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\VC\Auxiliary\Build\vcvars64.bat
+      APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2019
     - TOOLSET: gcc
       CXXSTD: 11,14,1z
       ADDPATH: C:\cygwin\bin;
@@ -43,10 +49,6 @@ environment:
       CXXSTD: 11,14,1z
       ADDPATH: C:\cygwin64\bin;
       APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2015
-    - TOOLSET: gcc
-      CXXSTD: 11,14,1z
-      ADDPATH: C:\mingw\bin;
-      APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2015
     - TOOLSET: gcc
       CXXSTD: 11,14,1z
       ADDPATH: C:\mingw-w64\x86_64-6.3.0-posix-seh-rt_v5-rev1\mingw64\bin;
@@ -80,6 +82,7 @@ build: off
 
 test_script:
   - PATH=%ADDPATH%%PATH%
+  - if not "%ENV_SCRIPT%" == "" call "%ENV_SCRIPT%"
   - if not "%CXXSTD%" == "" set CXXSTD=cxxstd=%CXXSTD%
   - if not "%ADDRMD%" == "" set ADDRMD=address-model=%ADDRMD%
   - b2 -j %NUMBER_OF_PROCESSORS% libs/iterator/test toolset=%TOOLSET% %CXXSTD% %ADDRMD%

include/boost/iterator/filter_iterator.hpp

@@ -104,7 +104,7 @@ public:
 
     template< typename OtherIterator, typename = enable_if_convertible_t< OtherIterator, Iterator > >
     filter_iterator(filter_iterator< Predicate, OtherIterator > const& t) :
-        super_t(t.base()), m_storage(t.m_storage.predicate(), m_storage.m_end)
+        super_t(t.base()), m_storage(t.m_storage.predicate(), t.m_storage.m_end)
     {}
 
     Predicate predicate() const { return m_storage.predicate(); }

include/boost/iterator/iterator_facade.hpp

@@ -9,6 +9,7 @@
 
 #include <cstddef>
 #include <memory>
+#include <utility>
 #include <type_traits>
 
 #include <boost/config.hpp>
@@ -346,63 +347,52 @@ class operator_brackets_proxy
     // Iterator is actually an iterator_facade, so we do not have to
     // go through iterator_traits to access the traits.
     using reference = typename Iterator::reference;
-    using value_type = typename Iterator::value_type;
 
 public:
-    operator_brackets_proxy(Iterator const& iter) :
+    explicit operator_brackets_proxy(Iterator const& iter) noexcept(std::is_nothrow_copy_constructible< Iterator >::value) :
         m_iter(iter)
     {}
 
-    operator reference() const
+    operator reference() const noexcept(noexcept(*std::declval< Iterator const& >()))
     {
         return *m_iter;
     }
 
-    operator_brackets_proxy& operator=(value_type const& val)
+    template< typename T >
+    typename std::enable_if<
+        detail::conjunction<
+            detail::negation<
+                std::is_same<
+                    operator_brackets_proxy< Iterator >,
+                    typename std::remove_cv< typename std::remove_reference< T >::type >::type
+                >
+            >,
+            std::is_assignable< reference, T&& >
+        >::value,
+        operator_brackets_proxy&
+    >::type operator= (T&& val) noexcept(noexcept(*std::declval< Iterator& >() = std::declval< T&& >()))
     {
-        *m_iter = val;
+        *m_iter = static_cast< T&& >(val);
         return *this;
     }
 
+    // Provides it[n]->foo(). Leverages chaining of operator->.
+    reference operator->() const noexcept(noexcept(*std::declval< Iterator const& >()))
+    {
+        return *m_iter;
+    }
+
+    // Provides (*it[n]).foo()
+    template< typename Ref = reference, typename Result = decltype(*std::declval< Ref >()) >
+    Result operator*() const noexcept(noexcept(**std::declval< Iterator const& >()))
+    {
+        return **m_iter;
+    }
+
 private:
     Iterator m_iter;
 };
 
-// A metafunction that determines whether operator[] must return a
-// proxy, or whether it can simply return a copy of the value_type.
-template< typename ValueType, typename Reference >
-struct use_operator_brackets_proxy :
-    public detail::negation<
-        detail::conjunction<
-            std::is_copy_constructible< ValueType >,
-            std::is_trivial< ValueType >,
-            iterator_writability_disabled< ValueType, Reference >
-        >
-    >
-{};
-
-template< typename Iterator, typename Value, typename Reference >
-struct operator_brackets_result
-{
-    using type = typename std::conditional<
-        use_operator_brackets_proxy<Value, Reference>::value,
-        operator_brackets_proxy<Iterator>,
-        Value
-    >::type;
-};
-
-template< typename Iterator >
-inline operator_brackets_proxy<Iterator> make_operator_brackets_result(Iterator const& iter, std::true_type)
-{
-    return operator_brackets_proxy< Iterator >(iter);
-}
-
-template< typename Iterator >
-inline typename Iterator::value_type make_operator_brackets_result(Iterator const& iter, std::false_type)
-{
-    return *iter;
-}
-
 // A binary metafunction class that always returns bool.
 template< typename Iterator1, typename Iterator2 >
 using always_bool_t = bool;
@@ -679,13 +669,9 @@ public:
     using difference_type = typename base_type::difference_type;
 
 public:
-    typename boost::iterators::detail::operator_brackets_result< Derived, Value, reference >::type
-    operator[](difference_type n) const
+    operator_brackets_proxy< Derived > operator[](difference_type n) const
     {
-        return boost::iterators::detail::make_operator_brackets_result< Derived >(
-            this->derived() + n,
-            std::integral_constant< bool, boost::iterators::detail::use_operator_brackets_proxy< Value, Reference >::value >{}
-        );
+        return operator_brackets_proxy< Derived >(this->derived() + n);
     }
 
     Derived& operator+=(difference_type n)

include/boost/iterator/transform_iterator.hpp

@@ -57,7 +57,7 @@ private:
         std::remove_reference< reference >
     >;
 
- public:
+public:
     using type = iterator_adaptor<
         transform_iterator< UnaryFunc, Iterator, Reference, Value >,
         Iterator,

meta/libraries.json

@@ -15,5 +15,5 @@
         "Thomas Witt <witt - at - acm.org>",
         "Jeffrey Lee Hellrung Jr. <jeffrey.hellrung -at- gmail.com>"
     ],
-    "cxxstd": "03"
+    "cxxstd": "11"
 }

test/iterator_adaptor_test.cpp

@@ -189,6 +189,16 @@ main()
     boost::const_nonconst_iterator_test(i, ++j);
   }
 
+  // Test that operator_brackets_proxy forwards operator-> and operator*
+  {
+    dummyT* ptr_array[] = { array + 0, array + 1, array + 2,
+                            array + 3, array + 4, array + 5 };
+
+    ptr_iterator<dummyT*> i(ptr_array);
+    BOOST_TEST_EQ(i[2]->foo(), 2);
+    BOOST_TEST_EQ((*i[2]).foo(), 2);
+  }
+
   int test;
   // Test the iterator_traits
   {