[libc++][ranges] P2542R8: Implement views::concat

libcxx/docs/FeatureTestMacroTable.rst

@@ -476,7 +476,7 @@ Status
     ---------------------------------------------------------- -----------------
     ``__cpp_lib_philox_engine``                                *unimplemented*
     ---------------------------------------------------------- -----------------
-    ``__cpp_lib_ranges_concat``                                *unimplemented*
+    ``__cpp_lib_ranges_concat``                                ``202403L``
     ---------------------------------------------------------- -----------------
     ``__cpp_lib_ratio``                                        ``202306L``
     ---------------------------------------------------------- -----------------

libcxx/docs/ReleaseNotes/21.rst

@@ -41,13 +41,15 @@ Implemented Papers
 - N4258: Cleaning-up noexcept in the Library (`Github <https://github.com/llvm/llvm-project/issues/99937>`__)
 - P0767R1: Deprecate POD (`Github <https://github.com/llvm/llvm-project/issues/104013>`__)
 - P1361R2: Integration of chrono with text formatting (`Github <https://github.com/llvm/llvm-project/issues/100014>`__)
+- P2542R8: ``views::concat`` (`Github <https://github.com/llvm/llvm-project/issues/105419>`__)
 - P2255R2: A type trait to detect reference binding to temporary (implemented the type traits only) (`Github <https://github.com/llvm/llvm-project/issues/105180>`__)
 - P2562R1: ``constexpr`` Stable Sorting (`Github <https://github.com/llvm/llvm-project/issues/105360>`__)
 - P0472R3: Put std::monostate in <utility> (`Github <https://github.com/llvm/llvm-project/issues/127874>`__)
 - P1222R4: A Standard ``flat_set`` (`Github <https://github.com/llvm/llvm-project/issues/105193>`__)
 - P2897R7: ``aligned_accessor``: An mdspan accessor expressing pointer over-alignment (`Github <https://github.com/llvm/llvm-project/issues/118372>`__)
 - P3247R2: Deprecate the notion of trivial types (`Github <https://github.com/llvm/llvm-project/issues/118387>`__)
 
+
 Improvements and New Features
 -----------------------------
 

libcxx/docs/Status/Cxx2cIssues.csv

@@ -68,8 +68,8 @@
 "`LWG4071 <https://wg21.link/LWG4071>`__","``reference_wrapper`` comparisons are not SFINAE-friendly","2024-06 (St. Louis)","|Complete|","19",""
 "`LWG4074 <https://wg21.link/LWG4074>`__","``compatible-joinable-ranges`` is underconstrained","2024-06 (St. Louis)","","",""
 "`LWG4076 <https://wg21.link/LWG4076>`__","``concat_view`` should be freestanding","2024-06 (St. Louis)","","",""
-"`LWG4079 <https://wg21.link/LWG4079>`__","Missing Preconditions in ``concat_view::iterator``\`s conversion constructor","2024-06 (St. Louis)","","",""
-"`LWG4082 <https://wg21.link/LWG4082>`__","``views::concat(r)`` is well-formed when ``r`` is an ``output_range``","2024-06 (St. Louis)","","",""
+"`LWG4079 <https://wg21.link/LWG4079>`__","Missing Preconditions in ``concat_view::iterator``\`s conversion constructor","2024-06 (St. Louis)","|Complete|","21",""
+"`LWG4082 <https://wg21.link/LWG4082>`__","``views::concat(r)`` is well-formed when ``r`` is an ``output_range``","2024-06 (St. Louis)","|Complete|","21",""
 "`LWG4083 <https://wg21.link/LWG4083>`__","``views::as_rvalue`` should reject non-input ranges","2024-06 (St. Louis)","","",""
 "`LWG4096 <https://wg21.link/LWG4096>`__","``views::iota(views::iota(0))`` should be rejected","2024-06 (St. Louis)","","",""
 "`LWG4098 <https://wg21.link/LWG4098>`__","``views::adjacent<0>`` should reject non-forward ranges","2024-06 (St. Louis)","","",""

libcxx/docs/Status/Cxx2cPapers.csv

@@ -54,7 +54,7 @@
 "`P3142R0 <https://wg21.link/P3142R0>`__","Printing Blank Lines with ``println``","2024-03 (Tokyo)","|Complete|","19","Implemented as a DR against C++23. (MSVC STL and libstdc++ will do the same.)"
 "`P2845R8 <https://wg21.link/P2845R8>`__","Formatting of ``std::filesystem::path``","2024-03 (Tokyo)","","",""
 "`P0493R5 <https://wg21.link/P0493R5>`__","Atomic minimum/maximum","2024-03 (Tokyo)","","",""
-"`P2542R8 <https://wg21.link/P2542R8>`__","``views::concat``","2024-03 (Tokyo)","","",""
+"`P2542R8 <https://wg21.link/P2542R8>`__","``views::concat``","2024-03 (Tokyo)","|Complete|","21",""
 "`P2591R5 <https://wg21.link/P2591R5>`__","Concatenation of strings and string views","2024-03 (Tokyo)","|Complete|","19",""
 "`P2248R8 <https://wg21.link/P2248R8>`__","Enabling list-initialization for algorithms","2024-03 (Tokyo)","","",""
 "`P2810R4 <https://wg21.link/P2810R4>`__","``is_debugger_present`` ``is_replaceable``","2024-03 (Tokyo)","","",""

libcxx/include/CMakeLists.txt

@@ -688,6 +688,7 @@ set(files
   __ranges/as_rvalue_view.h
   __ranges/chunk_by_view.h
   __ranges/common_view.h
+  __ranges/concat_view.h
   __ranges/concepts.h
   __ranges/container_compatible_range.h
   __ranges/counted.h