##
# A List is a homogeneous set of ListItems.
#
# The supported list types include:
#
# :BULLET::
#   An unordered list
# :LABEL::
#   An unordered definition list, but using an alternate RDoc::Markup syntax
# :LALPHA::
#   An ordered list using increasing lowercase English letters
# :NOTE::
#   An unordered definition list
# :NUMBER::
#   An ordered list using increasing Arabic numerals
# :UALPHA::
#   An ordered list using increasing uppercase English letters
#
# Definition lists behave like HTML definition lists.  Each list item can
# describe multiple terms.  See RDoc::Markup::ListItem for how labels and
# definition are stored as list items.

class RDoc::Markup::List

  ##
  # The list's type

  attr_accessor :type

  ##
  # Items in the list

  attr_reader :items

  ##
  # Creates a new list of +type+ with +items+.  Valid list types are:
  # +:BULLET+, +:LABEL+, +:LALPHA+, +:NOTE+, +:NUMBER+, +:UALPHA+

  def initialize type = nil, *items
    @type = type
    @items = []
    @items.concat items
  end

  ##
  # Appends +item+ to the list

  def << item
    @items << item
  end

  def == other # :nodoc:
    self.class == other.class and
      @type == other.type and
      @items == other.items
  end

  ##
  # Runs this list and all its #items through +visitor+

  def accept visitor
    visitor.accept_list_start self

    @items.each do |item|
      item.accept visitor
    end

    visitor.accept_list_end self
  end

  ##
  # Is the list empty?

  def empty?
    @items.empty?
  end

  ##
  # Returns the last item in the list

  def last
    @items.last
  end

  def pretty_print q # :nodoc:
    q.group 2, "[list: #{@type} ", ']' do
      q.seplist @items do |item|
        q.pp item
      end
    end
  end

  ##
  # Appends +items+ to the list

  def push *items
    @items.concat items
  end

end

