cpp-cheatsheet: A Comprehensive Modern C++ Reference Guide

Introduction

The cpp-cheatsheet repository, maintained by mortennobel, provides a concise and comprehensive reference for modern C++. This cheatsheet is an invaluable resource for anyone working with C++, specifically focusing on features introduced in C++11 and C++14. It is based on Phillip M. Duxbury's C++ Cheatsheet and further edited by Morten Nobel-Jørgensen, with C++11 additions inspired by ISOCPP.org. The primary goal is to offer a clear, quick overview of essential C++ concepts and standard library components.

Installation

To make use of the cpp-cheatsheet, there is no traditional "installation" required as it is a documentation-based repository. You can access the full content directly on GitHub or clone the repository to have a local copy for offline reference.

To clone the repository, use the following command:

git clone https://github.com/mortennobel/cpp-cheatsheet.git

Once cloned, you can open the README.md file in your preferred markdown viewer or directly browse the content in your terminal.

Examples

The cheatsheet covers a wide range of C++ topics, from basic syntax to advanced features and standard library usage. Here are a few examples of the structured information you'll find:

Preprocessor

                            // Comment to end of line
                            /* Multi-line comment */
#include  <stdio.h>         // Insert standard header file
#include "myfile.h"         // Insert file in current directory
#define X some text         // Replace X with some text
#define F(a,b) a+b          // Replace F(1,2) with 1+2
#define X \
 some text                  // Multiline definition
#undef X                    // Remove definition
#if defined(X)              // Conditional compilation (#ifdef X)
#else                       // Optional (#ifndef X or #if !defined(X))
#endif                      // Required after #if, #ifdef

Literals

255, 0377, 0xff             // Integers (decimal, octal, hex)
2147483647L, 0x7fffffffl    // Long (32-bit) integers
123.0, 1.23e2               // double (real) numbers
'a', '\141', '\x61'         // Character (literal, octal, hex)
'\n', '\\', '\'', '\"'      // Newline, backslash, single quote, double quote
"string\n"                  // Array of characters ending with newline and \0
"hello" "world"             // Concatenated strings
true, false                 // bool constants 1 and 0
nullptr                     // Pointer type with the address of 0

Memory Management with shared_ptr

#include <memory>           // Include memory (std namespace)
shared_ptr<int> x;          // Empty shared_ptr to a integer on heap. Uses reference counting for cleaning up objects.
x = make_shared<int>(12);   // Allocate value 12 on heap
shared_ptr<int> y = x;      // Copy shared_ptr, implicit changes reference count to 2.
cout << *y;                 // Dereference y to print '12'
if (y.get() == x.get()) {   // Raw pointers (here x == y)
    cout << "Same";  
}  
y.reset();                  // Eliminate one owner of object
if (y.get() != x.get()) { 
    cout << "Different";  
}  
if (y == nullptr) {         // Can compare against nullptr (here returns true)
    cout << "Empty";  
}  
y = make_shared<int>(15);   // Assign new value
cout << *y;                 // Dereference x to print '15'
cout << *x;                 // Dereference x to print '12'

Why Use This

The cpp-cheatsheet is an excellent resource for several reasons:

• Comprehensive Coverage: It provides a broad overview of C++ syntax, standard library components, and modern features up to C++14.
• Quick Reference: Its concise format makes it perfect for quickly looking up syntax or function signatures during development or study.
• Educational Tool: Ideal for students learning C++ or experienced developers brushing up on specific topics.
• Modern C++ Focus: Explicitly highlights C++11 and C++14 additions, ensuring relevance for contemporary projects.
• Community Driven: The repository encourages comments and feedback, fostering continuous improvement.

Links

• GitHub Repository: https://github.com/mortennobel/cpp-cheatsheet