class Chronic::Grabber

def self.scan(tokens)
  tokens.each_index do |i|
    if t = self.scan_for_all(tokens[i]) then tokens[i].tag(t); next end
  end
  tokens
end

def self.scan_for_all(token)
  scanner = {/last/ => :last,
             /this/ => :this,
             /next/ => :next}
  scanner.keys.each do |scanner_item|
    return self.new(scanner[scanner_item]) if scanner_item =~ token.word
  end
  return nil
end

def to_s
  'grabber-' << @type.to_s
end