Bite-sized C++ learning The ultimate collection of C++ patterns, idioms, tricks
Browse all posts Search posts

Featured

  • Delegating Constructor

    Reduce constructor boilerplate by delegating to another constructor in the same class.

    class Foo {
  Foo(int x)
    : Foo(x, 'y') {}
  Foo(int x, char y)
    : x(x), y(y) {}
};

  • Member Initialiser List

    Initialise class member variables before the constructor body runs.

    class Foo {
  Foo(int arg) : val(arg) {}
  int val;
};

  • Structured Binding

    Unpack pairs, tuples, and aggregates cleanly.

    auto [x, y] = std::pair#include <utility>{1, 2};

Recently Updated

See more

  • Class

    User-defined type that groups data and functions.

    class Circle {
public:
  double area() { return 3.14 * radius * radius; }
  double radius;
};

  • Const Method

    Member function that cannot modify the object it is called on.

    class Foo {
public:
  int get() const { return val; }
private:
  int val;
};

  • Const Variable

    Declare a variable whose value cannot change after initialisation.

    const int size = 100;
size = 200;  // ERROR.

  • Default Constructor

    Constructor that can be called with no arguments.

    class Foo {
public:
  Foo() : val(0) {}
  int val;
};

Foo obj;  // Calls Foo().

  • Reference

    Alias for an existing variable.

    int var = 1;
int& ref = var;  // ref is an alias for var.
ref = 2;         // var is now 2.

  • Static Member

    Class member shared by all objects.

    class Shape {
public:
  static int count;
};

Shape::count;

  • New and Delete

    Allocate and free memory at runtime.

    int* ptr = new int(1);
delete ptr;

int* arr = new int[3]{1, 2, 3};
delete[] arr;

  • Pointer

    Variable that stores the memory address of another variable.

    int var = 1;
int* ptr = &var;  // Address of var.
*ptr = 2;         // var = 2.

For Beginners

See more

  • Access Specifier

    Set class member accessibility.

    class Example {
public:
protected:
private:
};

  • Boolalpha

    Print booleans as "true"/"false" strings instead of the default 1/0.

    std::cout#include <iostream> << std::boolalpha#include <iostream>
  << true << "\n"
  << false << "\n";

  • Character Input

    Write to standard input using I/O streams.

    #include <iostream>
std::cin#include <iostream> >> var;

  • Character Output

    Print to standard output using I/O streams.

    #include <iostream>
std::cout#include <iostream> << var << "\n";

  • Delegating Constructor

    Reduce constructor boilerplate by delegating to another constructor in the same class.

    class Foo {
  Foo(int x)
    : Foo(x, 'y') {}
  Foo(int x, char y)
    : x(x), y(y) {}
};

  • Member Initialiser List

    Initialise class member variables before the constructor body runs.

    class Foo {
  Foo(int arg) : val(arg) {}
  int val;
};

  • Range-Based For Loop

    Loop over containers without writing indices or iterators.

    for (auto& element : container) {
  // Do something with element.
}

  • Structured Binding

    Unpack pairs, tuples, and aggregates cleanly.

    auto [x, y] = std::pair#include <utility>{1, 2};