github ericniebler/range-v3 0.11.0
Thanks, ISO

Released: August 6, 2020

IMPORTANT: This release removes the heuristic that tries to guess whether a range type
is a "view" (lightweight, non-owning range), in accordance with the C++20. This is a
potentially source-breaking change.
Code that previously used an rvalue range as the
start of a pipeline could stop compiling if the range library is not explicitly told that
that range type is a view. To override the new default, please specialize the
ranges::enable_view<R> Boolean variable template.

IMPORTANT: This release removes the implicit conversion from views to containers.
To construct a container from an arbitrary range, you must now explicitly use
ranges::to. For example, the following code no longer works:

std::vector<int> is = ranges::views::ints(0, 10); // ERROR: no conversion

Instead, please write this as:

auto is = ranges::views::ints(0, 10) | ranges::to<std::vector>; // OK

ranges::to lives in header <range/v3/range/conversion.hpp>

IMPORTANT: This release drops support for llvm-3.9.


  • NEW: A new concepts portability layer that short-circuits atomic constraints
    in requires clauses for better compile times when emulating concepts.
  • NEW: Restored support for MSVC in /std:c++17 mode, and for MSVC's default preprocessor.
  • Remove the implicit conversion from views to containers.
  • Rename the following entities to be consistent with C++20's std::ranges support:
    • safe_range<R> -> borrowed_range<R>
    • enable_safe_range<R> -> enable_borrowed_range<R>
    • safe_iterator_t<R> -> borrowed_iterator_t<R>
    • safe_subrange_t<R> -> borrowed_subrange_t<R>
    • readable_traits<I> -> indirectly_readable_traits<I>
    • readable<I> -> indirectly_readable<I>
    • writable<I> -> indirectly_writable<I>
  • Added the following to the ranges::cpp20 namespace:
    • Algorithm for_each_n
    • Algorithm sample
    • Class view_base
    • Alias views::all_t
  • Type __int128 is recognized as "integer-like".
  • Adds concepts three_way_comparable[_with] when <=> is supported.
  • Adds concepts partially_ordered[_with].
  • Better conformance with C++20's use of the boolean-testable concept.
  • Support C++20 coroutines.
  • Honor CMake's CMAKE_CXX_STANDARD variable.
  • A fix for the cardinality of views::zip[_with] (#1486).
  • Add view_interface::data() member function.
  • Add necessary specializations for std::basic_common_reference and
  • Numerous workarounds for MSVC.
  • Various CMake fixes and improvements.
  • drop_while_view is not a sized_range.
  • Added support for Wind River Systems.
  • Bug fixes to views::group_by (#1393).
  • common_[reference|type] of common_[tuple|pair] now yields a common_[tuple|pair]
    instead of a std::[tuple|pair] (#1422).
  • Avoid UB when currying an lvalue in some views and actions (#1320).

Credits: I would like to thank the following people who contributed to this release
(in no particular order): Christopher Di Bella, @marehr, Casey Carter, Dvir Yitzchaki,
Justin Riddell, Johel Ernesto Guerrero Peña, Barry Revzin, Kamlesh Kumar, and Vincas

10 months ago