CPP Templates & Generic Programming 3

Question 1

What does 'template argument deduction' do?

Accepted Answer

Automatically infers template parameters from function arguments at the call site

Answer

Template argument deduction lets the compiler infer template parameters from the types of function call arguments without explicit specification.

Question 2

Which template feature allows a single template to handle both lvalue and rvalue references universally?

Accepted Answer

Forwarding references (universal references) with T&&

Answer

When `T&&` appears in a deduced context, it becomes a forwarding (universal) reference that binds to both lvalues and rvalues.

Question 3

What does `std::forward<T>(arg)` do in a template function?

Accepted Answer

Preserves the value category (lvalue or rvalue) of the argument when forwarding

Answer

`std::forward<T>` performs a conditional cast that maintains the original value category, enabling perfect forwarding.

Question 4

Which of the following is true about partial template specialization?

Accepted Answer

It allows specializing a template for a subset of its parameters while leaving others generic

Answer

Partial specialization lets you fix some template parameters (e.g., specialize `Pair<T, int>`) while keeping others generic; this is only allowed for class/variable templates.

Question 5

What is the primary use of `std::type_traits` in template metaprogramming?

Accepted Answer

Compile-time type introspection and transformation

Answer

`` provides compile-time predicates (e.g., `std::is_integral`) and transformations (e.g., `std::remove_const`) on types.

(CPP) C++ Programming Professional Certificate Practice Test

(CPP) C++ Programming Professional Certificate Practice Test

CPP Templates & Generic Programming 3