From: David Tran <email55555@...>
Date: 2005-10-26T04:04:51+09:00
Subject: Redefine minus unary method

class Integer
  def +@
    super
    puts 'redefine + unary'
    self
  end

  def -@
    super
    puts 'redefine - unary'
    self
  end
end

+(2)  # print out 'redefine + unary'
-(2)  # nothing print out, why ?

a = 4
a = +a  # print out 'redefine + unary'
a = -a  # nothing print out, why ?