C++ is a high-performance, general-purpose programming language created as an extension of the C programming language. It provides object-oriented features, generic programming, and low-level memory manipulation.
C++ Anti-Patterns Overview
C++, despite its power and flexibility, has several common anti-patterns that can lead to bugs, performance issues, and maintenance problems. Here are the most important anti-patterns to avoid when writing C++ code.
Raw Pointer Ownership
Raw pointers don’t express ownership, leading to memory leaks or double-free errors. Use smart pointers (std::unique_ptr
, std::shared_ptr
) to clearly express ownership semantics.
Manual Resource Management
Manual resource management is error-prone. Use RAII (Resource Acquisition Is Initialization) to automatically manage resources through object lifetimes.
Not Using const Correctly
Use const
for methods that don’t modify object state, parameters that shouldn’t be modified, and return values that shouldn’t be modified.
Using Raw Loops Instead of Algorithms
Standard algorithms are more expressive, less error-prone, and often more efficient than raw loops. Use them whenever possible.
Premature Optimization
Write clear, maintainable code first, then optimize only after profiling identifies bottlenecks.
Not Using Modern C++ Features
Use modern C++ features like std::string
, std::string_view
, std::optional
, std::variant
, and others to write safer, more expressive code.
Not Using nullptr
Use nullptr
instead of NULL
or 0
for null pointers. It’s type-safe and avoids ambiguity with integer literals.
Not Using auto for Complex Types
Use auto
for complex types to improve readability and maintainability, especially for iterators and lambda types.
Not Using Range-Based For Loops
Use range-based for loops for cleaner, more readable iteration over containers.
Not Using Structured Bindings
Use structured bindings (C++17) to unpack tuples, pairs, and other structured data more cleanly.
Not Using std::optional
Use std::optional
(C++17) to represent values that may or may not be present, instead of using special values or output parameters.
Not Using std::variant
Use std::variant
(C++17) for type-safe unions, and std::visit
with overloaded lambdas for processing.
Not Using Move Semantics
Use move semantics to avoid unnecessary copying of large objects, especially when transferring ownership.
Not Using std::string_view
Use std::string_view
(C++17) for functions that only need to read string data, to avoid unnecessary copies.
Not Using Proper Exception Handling
Use proper exception handling to deal with errors, and consider using the “Resource Acquisition Is Initialization” (RAII) pattern to ensure resources are properly cleaned up.
Not Using Proper Memory Management
Use containers and smart pointers instead of manual memory management to avoid memory leaks and other memory-related bugs.
Not Using Rule of Zero/Three/Five
Follow the Rule of Zero (use standard containers and smart pointers), or the Rule of Five (define all special member functions) to properly manage resources.
Not Using Forward Declarations
Use forward declarations instead of including headers when you only need to refer to a class by pointer or reference, to reduce compilation dependencies and build times.
Not Using Proper Initialization
Always initialize variables to avoid undefined behavior. Use uniform initialization (curly braces) when appropriate.
Not Using Proper Error Handling
Use exceptions for exceptional conditions, and consider using std::expected
(C++23) or similar for expected failures.