# File lib/facet/harray.rb, line 278
  def fill(f,s=nil,l=nil)
    if s.kind_of?(Range)
      r = s
    else
      s = 0 if !s
      l = self.length - s if !l
      r = s...(s+l)
    end
    r.each{ |i| self.set(i,f) }
    self
  end