njlr

main:                                   # @main
        mov     eax, 16
        ret

njlr

constexpr int square(int x) { 
  return x * x;
}

int main() {
    return square(4);
}

njlr

Name	Ownership	Copyable	Movable	Sharing	Lifetime	Semantics
unique_ptr	Unique	❌	✅	❌	Lexical	Reference
shared_ptr	Shared	✅	✅	Reference	Reference-counted	Reference
weak_ptr	❌	✅	✅	❌	Non-extending	Optional-reference
value_ptr	Unique	✅	✅	Value	Lexical	Value

njlr

struct Foo::Pimpl {
  int x;
  int bar() { return ++x; }
};

Foo::Foo(int x) 
  : ptr{Foo::Pimpl{x}}
{}

njlr

struct Foo {
  int bar() { 
    return ptr->bar(); 
  }

  Foo(int x); 
  
  // Thanks to value_ptr we get value semantics for free
  Foo(Foo const&) = default;
  Foo& operator=(Foo const&) = default;

njlr

struct Tree {
  string const name;
  value_ptr<Tree> left;
  value_ptr<Tree> right;
  
  Tree(
    string const& name, 
    value_ptr<Tree> const& left = value_ptr<Tree>{}, 
    value_ptr<Tree> const& right = value_ptr<Tree>{})
    : name{name}

njlr

struct Node {
  string name;
  weak_ptr<Node> parent;
  vector<shared_ptr<Node>> children;
  
  bool hasParent() {
    return parent.expired();
  }
  
  shared_ptr<Node> getParent() {

njlr

struct Texture {
  Texture(string const& path) { cout << "Texture loaded from " << path << endl; }
  ~Texture() { cout<< "Texture destroyed" << endl; }
 
  static shared_ptr<Texture> load(string const& path) {
    return make_shared<Texture>(path)
  }
};

int doSomethingWithTexture(shared_ptr<Texture> const tex);

njlr

struct Widget {
  Widget() { cout << "Widget created" << endl; }
  ~Widget() { cout << "Widget destroyed" << endl; }
};

unique_ptr<Widget> createWindow() {
  return make_unique<Widget>();
}

int main() {

njlr

void* x = createInstance();
int* y = new int(); 
foo.bar(y);