» Abusing Ruby's question mark methods.

I've always enjoyed the ruby convention of using question marks to denote boolean methods. empty?, exist?, any?, alive?, etc... They're concise and easy to read. I do have one gripe with it, sometimes testing the inverse makes my code read like yoda wrote it.

not sting.empty?
not path.file?
not param.blank?

In rails I use not something.blank? a lot, so creating a not_blank? method wrapper around blank? was a nice simple fix. But I'm lazy and easily give into the temptation of the dark side, so I created a Bizarro Object. Which lets me do this...

# Meaningless examples that prove my point

"".not.empty?       #=> false
"words".not.empty?  #=> true

0.not.zero?         #=> false
1.not.zero?         #=> true

And here is the bit of code that makes it work...

class BizarroObject
  # Since this is a proxy, get rid of every default method
  # Copied from Jim Weirich's BlankSlate class
  # http://onestepback.org/index.cgi/Tech/Ruby/BlankSlate.rdoc
  instance_methods.each { |m| undef_method m unless m =~ /^__/ }

  # Takes an object as a parameter and will invert the return values of all it's methods.
  def initialize(object)
    @object = object
  end

  def method_missing(symbol, *args)
    !@object.send(symbol, *args)
  end
end

class Object
  # This is where the proxy/bizarro object is created
  def not
    BizarroObject.new(self)
  end
end

It's not optimized, and it's a little ridiculous, but I love that ruby lets me abuse it like this.

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