Useful things of modern C++

Modern C++ is (in my understanding) everything that starts with the C++11 standard. Which is already 9 years old. And just recently I decided to brush up on my knowledge of this wonderful PL, for which I found and collected all the features of C++11, C++14 and C++17 that are interesting for me personally. The result is this memo, which is needed primarily for me to systematize knowledge and as a small reference book.

Let's start with what's new in C++11.

1. https://en.cppreference.com/w/cpp/language/static_assert

Since C++11 it is possible to use static_assert (and in C++17 this mechanism is simplified) for compile-time checks. And rather “smart” development environments (for example, Visual Studio 2019) do such checks at the stage of editing the source code.



2. https://en.cppreference.com/w/cpp/language/auto

Automatic type deduction greatly simplifying, for example, looping through STL containers:



3. https://en.cppreference.com/w/cpp/language/function#Deleted_functions

You can “disable” certain functions of a class, for example, the default constructor.



4. https://en.cppreference.com/w/cpp/language/final

You can “finalize” a class or function, making overriding or inheritance impossible:



5. https://en.cppreference.com/w/cpp/language/override

The override keyword can be used to explicitly indicate the intent to override a function. Tighter control over the inheritance mechanism is of course useful.



6. https://en.cppreference.com/w/cpp/language/move_assignment
https://en.cppreference.com/w/cpp/language/move_constructor
https://en.cppreference.com/w/cpp/utility/move

No more temporary objects!



7. https://en.cppreference.com/w/cpp/language/enum

The enumeration type has become more useful due to the ability to explicitly set the type of a value and restrict access to its elements by the requirement of explicitly specify enumeration name.



8. https://en.cppreference.com/w/cpp/language/user_literal

User-defined literals allow you to make your code more readable by hiding the function call behind a nice-looking declaration.



9. https://en.cppreference.com/w/cpp/language/list_initialization

Initialization list simplifies initialization of STL containers (and may be used for user class).



10. https://en.cppreference.com/w/cpp/language/initializer_list#Delegating_constructor

Now one constructor can call another.



11. https://en.cppreference.com/w/cpp/language/nullptr

Finally, no more NULL macros and stuff like that. There is now a special data type for this.



12. https://en.cppreference.com/w/cpp/language/types#Character_types
https://en.cppreference.com/w/cpp/language/string_literal

Enhanced Unicode support at the level of language types and literals:



13. https://en.cppreference.com/w/cpp/language/lambda

One of the most useful innovations. Allows you to declare functions exactly where they are needed. Although I would not abuse this possibility.



14. https://en.cppreference.com/w/cpp/language/range-for

Now, instead of using indices and iterators, you can get by with this simple and neat construction:



15. https://en.cppreference.com/w/cpp/header/array

More safe and convenient replacement for C-style arrays.



16. https://en.cppreference.com/w/cpp/header/random

Much more advanced random number generation possibilities.



17. https://en.cppreference.com/w/cpp/header/regex

Finally, regular expressions are part of the standard library!



18. https://en.cppreference.com/w/cpp/thread
https://en.cppreference.com/w/cpp/header/thread
https://en.cppreference.com/w/cpp/header/mutex
https://en.cppreference.com/w/cpp/header/condition_variable
https://en.cppreference.com/w/cpp/header/future
https://en.cppreference.com/w/cpp/atomic

Multithreading is now supported by the standard library. A very useful innovation.



I found two interesting innovations in C++14:

19. https://en.cppreference.com/w/cpp/language/integer_literal

Binary literals allow you to write numbers in binary form:



20. Ability to use a separator in numeric literals:



More cool stuff in C++17 (plus the previously mentioned simplification for static_assert).

21. https://en.cppreference.com/w/cpp/language/attributes

An attribute indicating that the presence of an unused entity is not an error. No more UNUSED macros.



22. https://en.cppreference.com/w/cpp/language/namespace

Declaration of nested namespaces is simplified:



23. https://en.cppreference.com/w/cpp/utility/any

A special data type can store the value of any type:



24. https://en.cppreference.com/w/cpp/header/variant

You no longer need to reinvent your variant type as it appeared in the standard library.



25. https://en.cppreference.com/w/cpp/header/optional

Optional function arguments and return values.



26. https://en.cppreference.com/w/cpp/header/string_view

Better, safer alternative to C-style strings.



27. https://en.cppreference.com/w/cpp/header/charconv

Another (seemingly faster) way to convert text to numbers and vice versa.



28. https://en.cppreference.com/w/cpp/algorithm/clamp

A simple function to limit a number on the lower and upper bounds.



29. https://en.cppreference.com/w/cpp/header/filesystem

Full-blown support of the file system. A lot of useful things, for example - getting a list of files in a directory.