Range library for C++11/14/17. This code is the basis of a formal proposal to add range support to the C++ standard library.
Why does C++ need another range library? Simply put, the existing solutions haven't kept up with the rapid evolution of C++. Range v3 is a library for the future C++. Not only does it work well with today's C++ -- move semantics, lambdas, automatically deduced types and all -- it also anticipates tomorrow's C++ with Concepts.
Range v3 forms the basis of a proposal to add range support to the standard library (N4128: Ranges for the Standard Library). It also will be the reference implementation for an upcoming Technical Specification. These are the first steps toward turning ranges into an international standard.
Check out the (woefully incomplete) documentation here.
Other resources (mind the dates, the library probably has changed since then):
- Talk: CppCon 2015: Eric Niebler "Ranges for the Standard Library", 2015.
- A slice of Python in C++, 07.12.2014.
- Actions (back then called Container Algorithms), 23.11.2014.
- Range comprehensions, 27.04.2014.
- Input iterators vs input ranges, 07.11.2013.
Design / Implementation:
- Rationale behind range-v3: N4128: Ranges for the standard library Revision 1, 2014.
- Ranges TS: N4560: C++ Extensions for Ranges, 2015.
- Implementation of customization points in range-v3:
- Proxy iterators in range-v3:
- Metaprogramming utilities:
- Concept emulation layer: Concept checking in C++11, 2013.
- C++Now 2014: Eric Niebler "C++11 Library Design", 2014.
Most of the source code in this project are mine, and those are under the Boost Software License. Parts are taken from Alex Stepanov's Elements of Programming, Howard Hinnant's libc++, and from the SGI STL. Please see the attached LICENSE file and the CREDITS file for the licensing and acknowledgments.
The code is known to work on the following compilers:
- clang 3.6.2 (or later)
- GCC 4.9.1 (or later) (C++14 support requires GCC 5.2; C++14 "extended constexpr" support is poor before 6.1.)
- "Clang with Microsoft CodeGen" (Clang/C2) VS2015 Update 3 (or later)
Development Status: This code is fairly stable, well-tested, and suitable for casual use, although currently lacking documentation. No promise is made about support or long-term stability. This code will evolve without regard to backwards compatibility.
0.3.5 February 17, 2018
- Rvalues may satisfy
view_interfacegets a bounds-checking
chunk_viewworks on Input ranges.
- Fix bug in
- Improved concept checks for
contiguous_iterator_tagiterator category tag.
action::insertavoids interfering with
vector's exponentional growth strategy.
- Add an experimental
sharedview for views that need container-like scratch space to do their work.
- Faster, simpler
ranges::reference_wrapperto avoid LWG#2993.
any_view, the type-erased view wrapper.
stride_viewno longer needs an
adjacent_filter_viewsupports bidirectional iteration.
view_adaptorcleanup to remove the need for a
mutabledata member holding the adapted view.
tail_viewof an empty range is an empty range, not undefined behavior.
- Various portability fixes for gcc and clang trunk.
- Rvalues may satisfy
0.3.0 June 30, 2017
- Input views may now be move-only (from @CaseyCarter)
any_views are now much more efficicient (from @CaseyCarter)
- Better support for systems lacking a working
<thread>header (from @CaseyCarter)
0.2.6 June 21, 2017
- Experimental coroutines with
ranges::optionalnow behaves like
- Extensive bug fixes with Input ranges (from @CaseyCarter)
- Experimental coroutines with
0.2.5 May 16, 2017
view::chunkworks on Input ranges (from @CaseyCarter)
for_each_nalgorithm (from @khlebnikov)
- Portability fixes for MinGW, clang-3.6 and -3.7, and gcc-7; and cmake 3.0
0.2.4 April 12, 2017 Fix the following bug:
vectorbroken on Clang 3.8.1 since ~last Xmas (ericniebler/range-v3#632).
0.2.3 April 4, 2017 Fix the following bug:
- iterators that return move-only types by value do not satisfy Readable (ericniebler/stl2#399).
0.2.2 March 30, 2017 New in this release:
view::linear_distribute(from,to,n)- A view of
to, distributed evenly.
view::indices(n)- A view of the indices
view::closed_indices(n)- A view of the indices
This release deprecates
view::ints(n)as confusing to new users.
0.2.1 March 22, 2017 New in this release:
0.2.0 March 13, 2017 Bring many interfaces into sync with the Ranges TS.
Many interfaces are simply renamed. The following table shows the old names and the new. (All names are in the
Old Name New Name
common_iteratornow requires that its two types (
Sentinel) are different. Use
common_iterator_t<I, S>to get the old behavior (i.e., if the two types are the same, it is an alias for
I; otherwise, it is
The following iterator adaptors now work with iterators that return proxies from their postfix increment operator (i.e.,
The following customization points are now implemented per the Ranges TS spec and will no longer find the associated unconstrained overload in namespace
(In practice, this has very little effect but it may effect overloading in rare situations.)
ranges::is_swappablenow only takes one template parameter. The new
ranges::is_swappable_with<T, U>tests whether
ranges::is_swappable<T>is equivalent to
ranges::is_swappable_with<T &, T &>.
The following object concepts have changed to conform with the Ranges TS specification, and approved changes (see P0547):
Viewconcept is no longer satisfied by reference types.
The syntax for defining a concept has changed slightly. See utility/iterator_concepts.hpp for examples.
0.1.1 Small tweak to
Writableconcept to fix #537.
0.1.0 March 8, 2017, Begin semantic versioning
I do this work because I love it and because I love C++ and want it to be as excellent as I know it can be. If you like my work and are looking for a way to say thank you, you can leave a supportive comment on my blog. Or you could leave me some kudos on my Open Hub range-v3 contribution page. Just click the Give Kudos button here.