CPP Exception Handling & Error Management 2

Question 1

What happens when an exception is thrown inside a destructor that is already executing due to stack unwinding?

Accepted Answer

std::terminate() is called

Answer

If a destructor throws while another exception is being propagated (stack unwinding), std::terminate() is called because two exceptions cannot be active simultaneously.

Question 2

Which of the following correctly creates a custom exception class that follows best practices?

Accepted Answer

class MyEx : public std::exception { public: const char* what() const noexcept override { return "error"; } };

Answer

Best practice is to inherit publicly from std::exception and override what() as const noexcept to match the base class contract.

Question 3

What does the noexcept specifier guarantee when applied to a function?

Accepted Answer

The compiler optimizes the function assuming no exceptions will propagate out

Answer

noexcept tells the compiler no exceptions will propagate out, enabling optimizations; if one does, std::terminate() is called.

Question 4

What is the output of: try { throw 42; } catch (double d) { cout << "double"; } catch (...) { cout << "other"; }

Accepted Answer

other

Answer

An int literal 42 does not match catch(double), so the catch-all handler catch(...) executes.

Question 5

Which function can be used to rethrow the currently active exception inside a catch block?

Accepted Answer

throw;

Answer

A bare throw; statement inside a catch block rethrows the currently active exception preserving its original type.

(CPP) C++ Programming Professional Certificate Practice Test

(CPP) C++ Programming Professional Certificate Practice Test

CPP Exception Handling & Error Management 2