Introduction
A good programming language helps the programmer by providing a more abstract way to express himself. It hides uninteresting details, provides convenient building blocks (such as the while construct), and, most of the time, allows the programmer to add building blocks himself (such as the sum operation). ◦•◦ JavaScript is the language that is, at the moment, mostly being used to do all kinds of clever and horrible things with pages on the World Wide Web. JavaScript is also used for scripting in a variety of applications and operating systems. Of special note is server-side JavaScript (SSJS), where the server portion of a web application is written in JavaScript, so a full application can be expressed in one programming language. CoffeeScript generates standard JavaScript code and can therefore be used in environments where standard JavaScript is accepted. It means that both browser portions and server portions can be written in CoffeeScript. CoffeeScript is a new language so it remains to be seen how popular it becomes for general application development, but if you are interested in programming, CoffeeScript is definitely a useful language to learn. Even if you do not end up doing much web programming, the mind-bending programs in this book will always stay with you, haunt you, and influence the programs you write in other languages. There are those who will say terrible things about JavaScript. Many of these things are true. When I was for the first time required to write something in JavaScript, I quickly came to despise the language. It would accept almost anything I typed, but interpret it in a way that was completely different from what I meant. This had a lot to do with the fact that I did not have a clue what I was doing, but there is also a real issue here: JavaScript is ridiculously liberal in what it allows. The idea behind this design was that it would make programming in JavaScript easier for beginners. In actuality, it mostly makes finding problems in your programs harder, because the system will not point them out to you. However, the flexibility of the language is also an advantage. It leaves space for a lot of techniques that are impossible in more rigid languages, and it can be used to overcome some of JavaScript’s shortcomings. After learning it properly, and working with it for a while, I have really learned to like this language. CoffeeScript repairs many of the confusing and cumbersome aspects of JavaScript, while keeping its underlying flexibility and beauty. It is doubleplusgood.
17