Learn++ Lesson 50: If Constexpr in C++ Programming
The if constexpr statement lets a template choose a code path at compile time. In this lesson, a generic get_value function handles both a pointer and a non-pointer value.
Lesson 50 introduces
- using if constexpr for compile-time branching
- checking a type with std::is_pointer_v<T>
- dereferencing a pointer only in the pointer branch
- returning a value directly for a non-pointer type
A small example looks like this
template<typename T> auto get_value(T t) {
if constexpr (std::is_pointer_v<T>) {
return *t;
} else {
return t;
}
}What you practice in the app
- Reading compile-time conditional logic
- Recognizing a pointer through a type trait
- Understanding why the non-applicable branch is discarded
- Applying one template to pointer and non-pointer inputs
- Connecting the example to short mobile-friendly practice
Challenge focus
The Lesson 50 challenge asks learners to fill in the function name and the two data types so the template handles both inputs and prints 10 10.
This lesson is available in the Learn++ Android app as part of short, mobile-friendly programming practice. Start learning at https://learnplusplus.online