C++
- Getting started with C++
- Awesome Book
- Awesome Community
- Awesome Course
- Awesome Tutorial
- Awesome YouTube
- Alignment
- Argument Dependent Name Lookup
- Arithmitic Metaprogramming
- Arrays
- Atomic Types
- Attributes
- auto
- Basic input/output in c++
- Basic Type Keywords
- Bit fields
- Bit Manipulation
- Bit Operators
- Build Systems
- C incompatibilities
- C++ Containers
- C++ Debugging and Debug-prevention Tools & Techniques
- C++ function "call by value" vs. "call by reference"
- C++ Streams
- C++11 Memory Model
- Callable Objects
- Classes/Structures
- Client server examples
- Common compile/linker errors (GCC)
- Compiling and Building
- Concurrency With OpenMP
- Const Correctness
- const keyword
- Constant class member functions
- constexpr
- Copy Elision
- Copying vs Assignment
- Curiously Recurring Template Pattern (CRTP)
- Data Structures in C++
-
Date and time using
header - decltype
- Design pattern implementation in C++
- Digit separators
- Enumeration
- Exceptions
- Explicit type conversions
- Expression templates
- File I/O
- Floating Point Arithmetic
- Flow Control
- Fold Expressions
- Friend keyword
- Function Overloading
- Function Template Overloading
- Futures and Promises
- Header Files
- Implementation-defined behavior
- Inline functions
- Inline variables
- Internationalization in C++
- Iteration
- Iterators
- Keywords
- Lambdas
- Layout of object types
- Linkage specifications
- Literals
- Loops
- Memory management
- Metaprogramming
- More undefined behaviors in C++
- Move Semantics
- mutable keyword
- Mutexes
- Namespaces
- Non-Static Member Functions
- One Definition Rule (ODR)
- Operator Overloading
- operator precedence
- Optimization
- Optimization in C++
- Overload resolution
- Parameter packs
- Perfect Forwarding
- Pimpl Idiom
- Pointers
- Pointers to members
- Polymorphism
- Preprocessor
- Profiling
- RAII: Resource Acquisition Is Initialization
- Random number generation
- Recursion in C++
- Recursive Mutex
- Refactoring Techniques
- References
- Regular expressions
- Resource Management
- Return Type Covariance
- Returning several values from a function
- RTTI: Run-Time Type Information
- Scopes
- Semaphore
- SFINAE (Substitution Failure Is Not An Error)
- Side by Side Comparisons of classic C++ examples solved via C++ vs C++11 vs C++14 vs C++17
- Singleton Design Pattern
- Smart Pointers
- Sorting
- Special Member Functions
- Standard Library Algorithms
- static_assert
- std::any
- std::array
- std::atomics
- std::forward_list
- std::function: To wrap any element that is callable
- std::integer_sequence
- std::iomanip
- std::map
- std::optional
- std::pair
- std::set and std::multiset
- std::string
- std::variant
- std::vector
- Storage class specifiers
- Stream manipulators
- Templates
- The ISO C++ Standard
- The Rule of Three, Five, And Zero
- The This Pointer
- Thread synchronization structures
- Threading
- Trailing return type
- type deduction
- Type Erasure
- Type Inference
- Type Keywords
- Type Traits
- Typedef and type aliases
- Undefined Behavior
- Unions
- Unit Testing in C++
- Unnamed types
- Unspecified behavior
- User-Defined Literals
- Using declaration
- Using std::unordered_map
- Value and Reference Semantics
- Value Categories
- Variable Declaration Keywords
- Virtual Member Functions
C++ Singleton Design Pattern
Remarks
A Singleton is designed to ensure a class only has one instance and provides a global point of access to it. If you only require one instance or a convenient global point of access, but not both, consider other options before turning to the singleton.
Global variables can make it harder to reason about code. For example, if one of the calling functions isn't happy with the data it's receiving from a Singleton, you now have to track down what is first giving the singleton bad data in the first place.
Singletons also encourage coupling, a term used to describe two components of code that are joined together thus reducing each components own measure of self-containment.
Singletons aren't concurrency friendly. When a class has a global point of access, every thread has the ability to access it which can lead to deadlocks and race conditions.
Lastly, lazy initialization can cause performance issues if initialized at the wrong time. Removing lazy initialization also removes some of the features that do make Singleton's interesting in the first place, such as polymorphism (see Subclasses).
Sources: Game Programming Patterns by Robert Nystrom
