What are some advanced features of C++15 templates?

What are some advanced features of C++15 templates?

C++15 introduced several advanced features for templates, including variable templates, which allow you to define templates for non-type values.

Can you explain variable templates with an example?

Sure! A variable template allows you to define a template for a variable. For example:

template <typename T>
constexpr T pi = T(3.1415926535897932385);

This defines a variable template pi that can be used with different types.

What about template parameter packs?

Template parameter packs allow you to accept an arbitrary number of template parameters. You can use them with variadic templates to create functions or classes that can handle multiple types.

Are there any new features related to type deduction?

Yes! C++15 introduced deduced return types, allowing you to omit the return type in certain cases. For example:

auto func() -> decltype(x + y) {
    return x + y;
}

This makes the code cleaner and easier to read.