What Are the Roles of Non-Type Parameters in Template Usage?

Template Parameters: Unveiling the Meaning of

When working with templates, the notation is commonly used to define type parameters. However, the declaration introduces a different type known as a non-type parameter. Non-type parameters extend the capabilities of templates, allowing them to operate on values beyond types themselves.

Specifically, non-type parameters can represent:

• Integral constant expressions (like integer literals or enumerations)
• Pointers
• References

In the parameter, N represents an integer constant expression, allowing the template to accept integer values.

Examples of Non-Type Parameters:

• Type Parameter: : Specifies the type of objects stored in a container.
• Integer Parameter: : Sets the size of a buffer in bytes.
• Function Pointer Parameter: : Stores a pointer to a function with specific parameters and return value.
• Reference Parameter: : Provides a link to a variable by reference, allowing modifications within the template.
• Template Parameter: class AllocatePolicy>: Identifies a template used in a resource allocation mechanism.

Templates Without Explicit Arguments:

While templates typically require explicit arguments, it is possible to define templates with default values. For instance, establishes a default size for a vector if no value is provided during object creation.

Syntax for Explicit Specializations:

The <> notation is reserved for explicit template specializations, differentiating it from templates with no parameters. In such cases, <> follows the template declaration, as in >

Understanding non-type parameters expands the versatility of templates, enabling them to work with a wider range of data and values beyond types, empowering developers to create flexible and expressive code.

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