Let's add some real and simple examples, such as calculating the factorial

[kniazkov]

The book does not contain a single example of a completely finished program that takes something as input from the command line, computes it, and then outputs the result (or saves it to a file). However, these are the majority of programs, at least of the ones we write.

I propose to give at least one such complete example, namely the calculation of the factorial. It is possible to write the whole program text, and then in additional chapters to break it down piece by piece. Using only this example, a programmer learning EO will immediately understand many aspects of programming in this language.