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rogramming is both a science and an art. Telling computers what to do with computer programs requires being able to think as both a scientist and an artist. Being an artist is essential for coming up with big ideas and being flexible enough to take unique approaches. Being a scientist is essential to understanding how and why certain methodologies need to be taken into account, and to approach testing and debugging from a logical perspective, rather than an emotional one. Luckily, you don t need to be an artist or a scientist already. As with training the body, programming exercises and thinking about how to solve problems train the mind to make you a better programmer. Anyone can learn to program. The only things that can stand in the way are a lack of commitment or confusing programming languages. Ruby is one of the easiest programming languages to learn, so that leaves commitment. Programming should be fun, even joyful, and if you re enjoying yourself, commitment comes naturally. By the time you reach the end of this chapter, I hope you can get a taste of the fun that lies ahead with the knowledge of a powerful yet deceptively simple programming language, and begin to feel excited about a future of programming nirvana!

n Note This chapter does not follow an instructional format as the subsequent chapters do. Instead I ll

just go from concept to concept quickly to give you a feel for Ruby as a language before getting down to the details later.

In 1, you focused on installing Ruby so that your computer can understand the language. At the end of the chapter, you loaded a program called irb. Microsoft Windows users ran an application called fxri. fxri and irb provide similar functions, so when I refer to irb, as it s officially known, be aware that you can use fxri instead if you re using Microsoft Windows.

Ch apt er 2 n p rOG r a MMING == J OY: a W h I S t Le -S t O p t O U r O F r U B Y a N D O B Je C t O r I e N t a t I O N

irb stands for Interactive Ruby. Interactive means that as soon as you type something, your computer will immediately attempt to process it. Sometimes this sort of environment is called an immediate or interactive environment.

Start irb (or fxri) and make sure a prompt appears, like so: irb(main):001:0> This prompt is not as complex as it looks. All it means is that you re in the irb program, you re typing your first line (001), and you re at a depth of 0. You don t need to place any importance on the depth element at this time. Type this after the preceding prompt and press Enter: 1 + 1 The result should come back quickly: 2. The entire process looks like this: irb(main):001:0> 1 + 1 => 2 irb(main):002:0> Ruby is now ready to accept another command or expression from you. As a new Ruby programmer, you ll spend a lot of time in irb testing concepts and building up insights into Ruby. It provides the perfect environment for tweaking and testing the language, as you cannot do any significant damage from within irb. If you explicitly ask Ruby to erase files on your drive, of course, that can happen, but you re not susceptible to crashing your computer or harming other programs in regular operation. irb s interactive environment also gives you the benefit of immediate feedback an essential tool when learning. Rather than writing a program in a text editor, saving it, getting the computer to run it, and then looking through the errors to see where you went wrong, you can just type in small snippets of code, press Enter, and immediately see what happens. If you want to experiment further, try other arithmetic such as 100 * 5, 57 + 99, or 10 50 (note that the division symbol/operator on a computer is the forward slash character, /).