Code golf in Ruby: What's your favourite trick?

Question

Anything that saves a few characters and produces horrible, unreadable code is fair game.

My favourite is cheating spacing with the ternary operator. If you're testing a question-mark-method (like .nil?), the only place you need a space is after the second question mark:

x.odd?? "odd":"even"

Answer 1

It doesn't save a lot of space, but one of my favorites I've seen was in this glorious bit of obfuscation.

def initialize*d;@d,=d;end

Almost nobody figured out what the def initialize*d bit did (it's equivalent to def initialize(*d) — the parens are optional since the parser knows * can't occur in the middle of a method name).

Answer 2

Here are some of my tricks:

• output with $> << 'whatever'
• iterate with .map when possible, it's shorter
• iterators are usually shorter than for loops
• you don't the final newline
• don't use ;
• kill newlines after block || and before block }