Kernel

# File lib/abstract.rb, line 64
def not_implemented     #:doc:
  backtrace = caller()
  method_name = (backtrace.shift =~ /`(\w+)'$/) && $1
  mesg = "class #{self.class.name} must implement abstract method '#{method_name}()'."
  #mesg = "#{self.class.name}##{method_name}() is not implemented."
  err = NotImplementedError.new mesg
  err.set_backtrace backtrace
  raise err
end