class Chronic::Ordinal

def self.scan(tokens, options)
  tokens.each do |token|
    if t = scan_for_ordinals(token) then token.tag(t) end
    if t = scan_for_days(token) then token.tag(t) end
  end
end

def self.scan_for_days(token)
  if token.word =~ /^(\d*)(st|nd|rd|th)$/
    unless $1.to_i > 31 || $1.to_i < 1
      OrdinalDay.new(token.word.to_i)
    end
  end
end

def self.scan_for_ordinals(token)
  Ordinal.new($1.to_i) if token.word =~ /^(\d*)(st|nd|rd|th)$/
end

def to_s
  'ordinal'
end