Paolo Perrotta - Metaprogramming Ruby 2: Program Like the Ruby Pros

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I was thirteen, and I was tired of hanging
out at the local toy shop to play Intellivision games. I wanted my own videogame console. Id been bugging my parents for a while,
with no success.

Then I found an alternative: I could play games on a computeras well. So I asked my parents to buy me one of those new8-bit computersyou know, to learn useful stuff. My dadagreed, and my mom took me to the shop and bought me aSinclair ZX Spectrum.

Mom, Dad Here is something that I shouldve told youmore often in my life: thank you. This book is dedicated tothe two of you. Im hoping it will make you proud, just likeyour once-kid is proud of you. And while Im here, I havesomething to confess about that life-changing day thirty yearsago: I didnt really want to learn stuff. I just wanted toplay.

In fact, thats what Ive been doing
all these years.

Ruby inherits characteristics from various languagesLisp, Smalltalk, C, and Perl, to name a few. Metaprogramming comes from Lisp (and Smalltalk). Its a bit like magic, which makes something astonishing possible. There are two kinds of magic: white magic, which does good things, and black magic, which can do nasty things. Likewise, there are two aspects to metaprogramming. If you discipline yourself, you can do good things, such as enhancing the language without tweaking its syntax by macros or enabling internal domain-specific languages. But you can fall into the dark side of metaprogramming. Metaprogramming can confuse easily.

Ruby trusts you. Ruby treats you as a grown-up programmer. It gives you great power, such as metaprogramming. But you need to remember that with great power comes great responsibility.

Enjoy programming in Ruby.

Thank you, Joe Armstrong, Satoshi Asakawa, Peter Bakhirev, Paul Barry, Juanjo Bazn, Emmanuel Bernard, Roberto Bettazzoni, Ola Bini, Piergiuliano Bossi, Simone Busoli, Alessandro Campeis, Kosmas Chatzimichalis, Andrea Cisternino, Davide DAlto, Pietro Di Bello, Mauro Di Nuzzo, Marco Di Timoteo, Paul Elliott, Eric Farkas, Mauricio Fernandez, Francisco Fernndez Castao, Jay Fields, Michele Finelli, Neal Ford, Florian Frank, Sanne Grinovero, Federico Gobbo, Florian Gro, Sebastian Hennebrder, Doug Hudson, Jurek Husakowski, Lyle Johnson, Lisa Maria Jones, Josh Kalderimis, Murtuza Kutub, Marc Lainez, Daniele Manni, Luca Marchetti, Arialdo Martini, Kado Masanori, MenTaLguY, Nicola Moretto, Sandro Paganotti, Alessandro Patriarca, Carlo Pecchia, Susanna Perrotta, John Pignata, Andrea Provaglio, Mike Roberts, Martin Rodgers, , Richard Schneeman, Joe Sims, Jeremy Sydik, Andrea Tomasini, Mauro Tortonesi, Marco Trincardi, Ivan Vaghi, Giancarlo Valente, Davide Varvello, Elzie Vergine.