C++ Tip of The Week

---

Your weekly dose of modern C++ challenge (Release every Sunday).

• https://tip-of-the-week.github.io/cpp

• How to contribute/add a solution?

  • Contributions are always very much appreciated. Just create a Pull Request with your solution.

---

Tips

C++26

• Did you know that C++26 added structured binding declaration as a condition?
• Did you know that C++26 added support constexpr placement new?
• Did you know that C++26 added = delete("should have a reason")?
• Did you know that C++26 added span.at?
• Did you know about C++26 simd proposal (1/N)?
• Did you know about C++26 simd proposal (2/N)?
• Did you know about C++26 static reflection proposal (1/N)?
• Did you know about C++26 static reflection proposal (2/N)?
• Did you know about C++26 static reflection proposal (3/N)?
• Did you know about C++26 static reflection proposal (4/N)?
• Did you know about C++26 static reflection proposal (5/N)?
• Did you know about C++26 static reflection proposal (6/N)?
• Did you know about C++26 static reflection proposal (7/N)?
• Did you know that C++26 added Pack Indexing?
• Did you know about C++26 proposal - variadic friends?
• Did you know about C++26 proposal - inplace_vector?
• Did you know about C++26 proposal - Aggregates are named tuples?
• Did you know that C++26 added new SI prefixes?
• Did you know that C++26 changed arithmetic overloads of std::to_string and std::to_wstring to use std::format?
• Did you know that C++26 added more constexpr for <cmath> and <complex>?
• Did you know that C++26 added testing for success or failure of <charconv> functions?
• Did you know that C++26 allows constexpr cast from void*?
• Did you know that C++26 added Member visit?
• Did you know that C++26 std.format added formatting pointers ability?
• Did you know that C++26 added 'A nice placeholder with no name'?
• Did you know that C++26 added user-generated static_assert messages?
• Did you know that C++26 added bind front and back to NTTP callables?
• Did you know that C++26 added `@, $, and `` to the basic character set?

C++23

• Did you know that C++23 added constexpr bitset?
• Did you know that C++23 added Explicit lifetime management (1/N)?
• Did you know that C++23 added spanstream - A strstream replacement using span as buffer?
• Did you know that C++23 added standard support for flat_map?
• Did you know that C++23 added range string_view constructor?
• Did you know that C++23 added std::invoke_r?
• Did you know that C++23 extended floating-point types?
• Did you know that C++23 deprecated std::aligned_storage and std::aligned_union?
• Did you know that C++23 added Monadic operations for std::expected?
• Did you know that C++23 added support for formatting ranges?
• Did you know that std::unique_ptr can be constexpr in C++23?
• Did you know that C++23 added static operator[]?
• Did you know that functions in <charconv> are constexpr since C++23?
• Did you know that C++23 added support for constexpr std::bitset?
• Did you know that C++23 added static operator()?
• Did you know that C++23 added stacktrace library?
• Did you know that [[assume]] attribute has been accepted to C++23?
• Did you know that C++23 added auto(x): decay-copy in the language?
• Did you know about C++23 ispanstream - A strstream replacement using span as buffer?
• Did you know that C++23 added ranges::to (conversion from ranges to containers)?
• Did you know that C++23 added Literal Suffix for (signed) size_t?
• Did you know that C++23 added bind_back to simplify writing higher order functions?
• Did you know about C++23 proposal Structured Bindings can introduce a Pack?
• Did you know that C++23 added std::to_underlying?
• Did you know that C++23 added std::unreachable?
• Did you know that C++23 added Attributes on Lambda-Expressions?
• Did you know that C++23 added std::byteswap to swap bytes?
• Did you know that type_info equality operator is constexpr in C++23?
• Did you know that C++23 added Monadic operations for std::optional?
• Did you know that C++23 added std::move_only_function?
• Did you know that C++23 added basic_string::resize_and_overwrite?
• Did you know that C++23 allows extended init-statement with alias-declaration in the for loop?
• Did you know that CRTP can be implemented with C++23 Deducing this?
• Did you know that Deducing this proposal has been voted out into C++23?
• Did you know that C++23 added if consteval?
• Did you know about C++23 feature which adds support for inheriting from std::variant?
• Did you know about C++23 feature which removes unnecessary ()’s from C++ lambdas?
• Did you know that C++23 added contains function to string_view?
• Did you know that C++23 added is_scoped_enum type trait to detect whether an enum is scoped?
• Did you know about C++23 proposal to add views::enumerate?
• Did you know that C++23 permitts static constexpr variables in constexpr functions?
• Did you know about proposal to add support for recursive lambdas?
• Did you know about proposal to add Compile Time Regular Expressions?

C++20

• Did you know that C++20 source_location can be used to get the member names?
• Did you know that C++20's no_unique_address can be used to find unique types?
• Did you know that C++20 added constinit keyword?
• Did you know about C++20 std::next_permutation algorithm?
• Did you know that C++20 added std::span?
• Did you know that with C++20 you can pass concepts?
• Did you know about C++20 is_layout_compatible_v type_traits?
• Did you know that C++20 added support for Unevaluated asm-declaration in constexpr functions?
• Did you know that C++20 added support for constexpr std::vector?
• Did you know that C++20 concepts can be used to avoid implicit conversions?
• Did you know that C++20 introduced coroutines? (co_await)
• Did you know that C++20 introduced coroutines? (co_yield)
• Did you know that with C++20 (constexpr containers) TMP can be achieved with STL?
• Did you know about C++20 template specialization with concepts?
• Did you know about introduced in C++20 object concepts?
• Did you know that C++20 made std::string constexpr?
• Did you know that C++20 added std::ranges::{all_of, any_of, none_of} algorithms?
• Did you know that C++20 added support for floating point values as non-type template parameters
• Did you know that C++20 added std::erase_if for std::map and std::vector?
• Did you know that C++20 added __VA_OPT__ for comma omission and comma deletion?
• Did you know that C++20 extends support for data time utilities?
• Did you know that C++20 added type_identity which implements the identity metafunction?
• Did you know that C++20 [[no_unique_address]] can be used to implement lazy/fast/memory efficient
• Did you know that C++20 made typename more optional?
• Did you know that C++20 std::to_array supports creating from string literals?
• Did you know that C++20 added Using Enum which introduces the enumerator names of the named enumeratio
• Did you know that C++20 added support for [[no_unique_address]] attribute?
• Did you know that C++20 added support for constexpr new?
• Did you know that C++20 added ostream_joiner that writes successive objects into the basic_ostr
• Did you know that Formatted output has been accepted into C++20?
• Did you know C++2X Pattern Matching can be used for run-time dispatching?
• Did you know about C++2X Pattern Matching proposal?
• Did you know about the proposal to add Non-terminal variadic template parameters?
• Did you know about the proposal to add constexpr function parameters?
• Did you know about Design By Introspection?
• Did you know that you can customize formatter for your classes with std::format?
• Did you know Non-Type Template Parameters (NTTP)?
• Did you know that static reflection supports introspecting constructors?
• Did you know that static reflection can be used to invoke functions with named parameters?
• Did you know that static reflection can be used to implement row polymorphism?
• Did you know that static reflection proposal for C++2X has mirror/value based interface?
• Did you know that static reflection proposal for C++2X can reflect functions?
• Did you know about static reflection proposal for C++2X?
• Did you know about the proposal to make printf compile-time safe and with named arguments?
• Did you know about proposal to introduce constexpr ternary operator?
• Did you know about the proposal to add json support to the standard library?
• Did you know about std::expected proposal for error handling?
• Did you know that Lambdas in Unevaluated Context combined with Template Constraints (Concepts)?
• Did you know that Lambdas in Unevaluated Context combined with Immediately Invoked Function Expression?
• Did you know that Compile Time Regular Expressions support extracting matches?
• Did you know about C++2X Pattern matching using is and as proposal?
• Did you know that tuple can be implement just with lambdas?
• Did you know that with concepts you can override a type?
• Did you know about (rejected) proposal for homogeneous variadic function parameters?
• Did you know that lambda expression is guaranteed to have a unique type?
• Did you know what is the underlying type of NTTP string aka fixed_string?
• Did you know that lambdas are const by default but can be mutable and keep state?
• Did you know that concept can be passed via lambda expression?

C++17

• Did you know that C++17 added Hardware interference size?
• Did you know that the underlying visit implementation of std::visit has changed since GCC12+, Clang15+?
• Did you know that run-time dispatching over type-list can be implemented many different ways?
• Did you know that you can simplify boost.mp11 API with DSL?
• Did you about C++17 std::index_sequence, std::make_index_sequence?
• Did you know that C++17 added std::pmr::polymorphic_allocator?
• Did you know that C++17 added std::forward_as_tuple and std::make_from_tuple and what’s the differ
• Did you know that C++17 [[nodiscard]] attribute can be applied not only to function?
• Did you know that C++17 structured bindings support to custom classes can be added?
• Did you know about C++17 variadic using declaration?
• Did you know that C++17 made exception specifications be part of the type system?
• Did you know about C++2X proposal to add Multidimensional subscript operator?
• Did you know that std::variant become valueless by exception?
• Did you know about std::rank/std::rank_v type_trait to get the rank of the array?
• Did you know that constexpr is strict about undefined behaviour (UB), object lifetime, etc?
• Did you know about Policy Based Design?
• Did you know about python's named tuples?
• Did you know about typename erasure technique to reduce compilation times with templates?
• Did you know that mapping types to values is a simple way to transition from compile-time to run-time?

C++14

• Did you know that in C++ you can generate jump tables at compile-time?
• Did you know that C++ allows to pass Pointer To Member Function via template parameter?
• Did you know about typename erasure technique (via Strong/Opaque Typedefs) in C++?
• Did you know about intrisincts to support SIMD (Single Instruction, Multiple Data) instructio
• Did you know DRY (Don’t Repeat Yourself) comparisons pattern?
• Did you know that you can implement a compile-time map with C++?
• Did you know about use cases for type-based reserved decorator?
• Did you know about Automatic Dependency Injection libraries such as DI?
• Did you know that with Automatic DI production wiring can be overwritten for integration testing?
• Did you know that with Automatic DI one can control how dependencies are being created?
• Did you know about different ways of constructor Dependency Injection?
• Did you know that the JSON standard does not specify that the insertion order of object elements?

C++11

• Did you know that C++11 allows calling functions with reference-to-array parameters from an initialize
• Did you know that C++11 added a numeric literal operator template?
• Did you know the difference between fakes, stubs, mocks?
• Did you know that you can inject singletons to improve testability?
• Did you know about memoized for less types (more compile-time friendly) conditional_t?
• Did you know about gtest.gmock mocking framework?
• Did you know about methods to access the last element of variadic pack...?
• Did you know that different overloads can have different specifiers?
• Did you know that C++ allows accessing private members with friend injection?
• Did you know about variadic aggregate initialization?
• Did you know that default template arguments can be explored with template template arguments?

C++98

• Did you know about virtual inheritance in C++?
• Did you know that the layout of struct fields will affect its size/alignment?
• Did you know that in C++ char, signed char and unsigned char are 3 different types?
• Did you know about function-try-block and that exceptions caught inside that block are implicitly
• Did you know that expression evaluation order is not specified?
• Did you know that sizeof operator can be used for efficient math computation?
• Did you know about different ways of iterating over objects?
• Did you know about if/else hell anti-pattern?
• Did you know you can pass an array by reference?
• Did you know that ANSI/ISO C++ conforming programs must not rely on a maximum template depth?
• Did you know wrapping an unqualified function name?
• Did you know about compiler predefined macros assosicated with the compilation date/time?
• Did you know about different ways of accessing C-style arrays by index?
• Did you know that using-declarator can be used to manipulate the overload set?

GNU-extensions

• Did you know about gnu::vector_size extension?
• Did you know about __builtin_dump_struct clang-extension which can nicely print a struct?
• Did you know about [[gnu::cold]] function attribute to mark functions which are unlikely to be called?

Circle

• Did you know that Circle supports Python's extended slice syntax for variadic packs?
• Did you know that Circle Meta-model allows to convert string to a type?
• Did you know that Circle Meta-model allows for applying normal STL for operations on @meta types?
• Did you know about C++2X proposal for the Circle Meta-model for compilation-time meta-progr

---

Disclaimer This repo orignates from https://quantlabfinancial.github.io/cpp_tip_of_the_week