Notes of Elements of Modern C++ Style

Notes of Sutter’s Elements of Modern C++ Style.

• Use auto whenever possible
  • Especially useful in writing lambda expression

auto const xlimit = config["xlimit"];
auto& s = singleton::instance();
auto x = [](int i) { return i > 42; };

• Don’t delete, use smart pointers
  • Only use raw pointers:
    • When non-owning (and you are sure it’s going to outlive you)
    • When implementing data structure
• Use nullptr, no more 0 or NULL
• Use range for
• Use non-member begin(x) and end(x)
  • And don’t write x.begin() and x.end() anymore
  • Because non-member version begin and end are extensible and can be adapted to work with even arrays
• lambda makes STL algorithm more usable (and many more library are designed around lambda)
• Move semantics change the way we design APIs
  • Design return-by-value more often
  • Move can be thought of as an optimization of copy
  • Also enable other things like perfect forwarding
• Prefer uniform initialization and initializer lists
  • That is, prefer {} over ()
  • This prevents:
    • Accidentally narrowing conversions (e.g., float to int)
    • Uninitialized POD member variables or arrays
    • Syntax ambiguity
  • But for non-POD and auto, continue using = syntax

// Is this a function declaration or a variable definition?
rectangle w(origin(), extents());

// But this is clear.
rectangle w{origin(), extents()};

// Continue using = syntax in these cases.
int a = 42;
auto x = begin(v);