Variable Templates

Variable Templates with Custom Types

Can I use variable templates with user-defined types?

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Yes, you can use variable templates with user-defined types. The type used in a variable template can be any valid C++ type, including user-defined types such as classes or structs. However, there are a few requirements for using user-defined types with variable templates:

  • The user-defined type must have a¬†constexpr¬†constructor that can accept the arguments passed to the variable template.
  • The user-defined type must be default-constructible if no arguments are provided to the variable template.

Here's an example of using a variable template with a user-defined type:

struct MyType {
  constexpr MyType(int value) : value(value) {}
  int value;
};

template <typename T>
constexpr T myVariable = T(42);

int main() {
  // v.value will be 42
  MyType v = myVariable<MyType>;
}

In this example, MyType is a user-defined type with a constexpr constructor that accepts an int value. The variable template myVariable is defined with a type parameter T and initializes the variable with T(42). When myVariable is instantiated with MyType, it creates an instance of MyType with the value 42.

This Question is from the Lesson:

Variable Templates

An introduction to variable templates, allowing us to create variables at compile time.

Answers to questions are automatically generated and may not have been reviewed.

This Question is from the Lesson:

Variable Templates

An introduction to variable templates, allowing us to create variables at compile time.

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