Ruby Unary operator overloading and it's oddities

unary-oddities.rb

### The 4 unaries are: + - ~ !
### If you really found more, tell me ;o)

class Foo
  def +@
    puts "unary plus (in front of object) / without param"
  end
  def -@(a=42)
    # please tell me, how could I pass an argument to an unary operation?
    # but it's possible to define arguments, curious ...
    puts "unary minus (in front of object) / with param: #{a}"
  end
  def -(nr)
    puts "binary minus! (behind object) / with param: #{nr}"
  end
end

f = Foo.new

+f   #=> unary plus (in front of object) / without param

-f   #=> unary minus (in front of object) / with param: 42

f-23 #=> binary minus! (behind object) / with param: 23

f.-@0#:D

Thanx. Very unreadable code then. :o)

(Damn, not to see the obvious.)

Yep, it's possible, but nobody uses such things ;). (Another example would be defining multiple args for <<)

Btw1: Overloading unary operators for symbols: http://rubyzucker.info/#unary

Btw2: Superators http://www.rubyinside.com/superators-add-new-operators-to-ruby-592.html xD

BTW: this gist was only a showcase for unary discussion on https://gist.github.com/1075747

The superators sound interesting, but not really functional (the gem is outdated / a trouble making issue was mentioned).

Would be really nice, if there is a possibility of defining own unary operators in Ruby.