Introduction to metaprogramming

The simplest way to say this is that metaprogramming is a technique that creates a code by using a code. Implementing metaprogramming, we write a computer program that manipulates the other programs and treats them as its data. In addition, templates are a compile-time mechanism in C++ that is Turing-complete, which means any computation expressible by a computer program can be computed, in some form, by a template metaprogram before runtime. It also uses recursion a lot and has immutable variables. So, in metaprogramming, we create code that will run when the code is compiled.

Preprocessing the code using a macro

To start our discussion on metaprogramming, let's go back to the era when the ANSI C programming language was a popular language. For simplicity, we used the C preprocessor by creating a macro. The C parameterized macro is also known as metafunctions, and is one of the examples of metaprogramming. Consider the following parameterized macro:

    #define...