C-stuff gpt notes

“Enforce move-only semantics” means: Your type cannot be copied (no duplicate owners), but it can be moved (ownership is transferred), and the moved-from object becomes empty but valid (e.g., holds nullptr) and can be destroyed/reset/reused safely. This is exactly the ownership model std::unique_ptr uses to avoid double-deletes

std::unique_ptr has an explicit operator bool() const noexcept that answers one question: “Do you currently own something?”

Conversion functions are user-defined implicit/explicit casts from your class type to some other type. What happens if you don’t write explicit? Then the conversion is implicit. That means your unique_ptr could be used anywhere a bool (or something convertible from bool) is expected — sometimes in ways you don’t want

These are the special member functions in C++: Default constructor T() Destructor ~T() Copy constructor T(const T&) Copy assignment operator T& operator=(const T&) Move constructor T(T&&) Move assignment operator T& operator=(T&&)

The compiler will generate these for you if you don’t declare them (with some rules). Together they’re often called the “big five” (used to be “big three” before move semantics).

Why noexcept Matters

1. Exception safety

   • Critical functions like destructors should never throw.
   • Without noexcept, throwing from a destructor during stack unwinding would cause std::terminate() anyway — so marking it makes intent explicit.

2. Compiler optimizations

   • Functions marked noexcept can skip exception-handling scaffolding.
   • This often results in smaller, faster code.

3. Container behavior

   • Standard containers (like std::vector) check if move constructors are noexcept.
   • If they are, the container will move elements during reallocation (faster).
   • If not, it will copy instead (slower, but safer).

Run cmake

Remove-Item -Recurse -Force .\build cmake -S . -B build # reconfigure; this refreshes the .vcxproj without the .cpp cmake --build build --config Debug -j