Alternatives and similar repositories for optional

Users that are interested in optional are comparing it to the libraries listed below

• cor3ntin / rangesnext
  ranges features for c+23 ported to C++20
  ☆76Updated 2 years ago
• jfalcou / kumi
  C++20 Compact Tuple Tools
  ☆57Updated 3 weeks ago
• boostorg / stl_interfaces
  A C++14 and later CRTP template for defining iterators
  ☆76Updated last month
• anthonywilliams / strong_typedef
  A class template that creates a new type that is distinct from the underlying type, but convertible to and from it
  ☆114Updated last year
• jbcoe / value_types
  value types for composite class design - with allocators
  ☆72Updated last month
• BobSteagall / wg21
  Various documents and code related to proposals for WG21
  ☆67Updated last year
• MiSo1289 / more_concepts
  A C++20 concepts library, providing container concepts etc.
  ☆88Updated last year
• apolukhin / pfr_non_boost
  Boost.PFR without the boost namespaces
  ☆76Updated 6 months ago
• boostorg / parser
  A C++ parser combinator library.
  ☆161Updated 3 weeks ago
• josuttis / belleviews
  bel::views - simple and easy view classes for C++
  ☆77Updated 2 years ago
• brevzin / cpp_proposals
  My WG21 proposals
  ☆64Updated this week
• DNKpp / mimicpp
  A modern and (mostly) macro free mocking-framework
  ☆55Updated last month
• bemanproject / beman
  Organization, documentation, etc. for the Beman Project,
  ☆111Updated 3 weeks ago
• boostorg / hash2
  A hash function library
  ☆49Updated last month
• bemanproject / inplace_vector
  A dynamically-resizable vector with fixed capacity and embedded storage (P0843)
  ☆28Updated this week
• tcsullivan / ini-config
  C++20 single-header library for embedding INI configs
  ☆60Updated 2 years ago
• mpusz / mp-coro
  Coroutine support tools
  ☆36Updated 3 months ago
• jbcoe / indirect_value
  An indirect value-type for C++
  ☆83Updated 2 years ago
• cppalliance / mrdocs
  MrDocs: A Clang/LLVM tool for building reference documentation from C++ code and javadoc comments.
  ☆142Updated 2 weeks ago
• koniarik / vari
  variadic pointers and references
  ☆22Updated 4 months ago
• reacfen / uninttp
  A universal type for non-type template parameters for C++20 or later.
  ☆28Updated last year
• cmannett85 / arg_router
  C++ command line argument parsing and routing
  ☆51Updated last year
• Thermadiag / seq
  The seq library is a collection of original C++17 STL-like containers and related tools
  ☆101Updated last month
• jfalcou / spy
  SPY - C++ Information Broker
  ☆157Updated last month
• HolyBlackCat / better_list_init
  List-initialize containers with proper move semantics
  ☆30Updated 9 months ago
• hanickadot / co_curl
  ☆81Updated 8 months ago
• dietmarkuehl / kuhllib
  an experimental standard C++ library
  ☆92Updated last year
• zhihaoy / nontype_functional
  Complete implementation of std::function, std::function_ref, and std::move_only_function
  ☆67Updated last month
• rollbear / lift
  constexpr C++17 library for simplifying higher order functions in application code
  ☆202Updated 2 years ago
• qlibs / ut
  C++20 Unit-Testing library
  ☆52Updated 8 months ago