# File lib/nice-ffi/pathset.rb, line 415
  def delete!( *regexps )
    case regexps[0]
    when :paths
      @paths.delete_if { |regexp, paths|  regexps.include? regexp }
    when :files
      @files.delete_if { |regexp, files|  regexps.include? regexp }
    when Symbol
      raise( "Invalid symbol option '#{first.inspect}'. " +
             "Expected :paths or :files." )
    else
      @paths.delete_if { |regexp, paths|  regexps.include? regexp }
      @files.delete_if { |regexp, files|  regexps.include? regexp }
    end
    self
  end