Today, I want to note down my thoughts on closures. Closures are important in Rust, because they are extensively used in iterator adapters paramount in development highly performant programs. However, to my point of view this topic is not well-covered in The Book. This may be a reason why it is considered among the most difficult parts of the language. In this post, I will try to shed more light on it, hopefully making it more clear to Rust learners. Note that I am still a novice to the language, and my understanding may not be fully correct.
When you develop your first binary application using new language, the first issue that you face is how to organize your code so that you can easily extend it in the future. There is a good example in The Book on how to organize your code, parse and process command line arguments by yourself. However, in real world you would use a library to parse command line arguments, which most probably would be the clap library in case of Rust. In this article, I describe my template for creating a CLI (command line interface) application.