/tools/Ruby/lib/ruby/1.8/rdoc/markup/simple_markup/lines.rb

  1##########################################################################
  2#
  3# We store the lines we're working on as objects of class Line.
  4# These contain the text of the line, along with a flag indicating the
  5# line type, and an indentation level
  6
  7module SM
  8
  9  class Line
 10    INFINITY = 9999
 11
 12    BLANK     = :BLANK
 13    HEADING   = :HEADING
 14    LIST      = :LIST
 15    RULE      = :RULE
 16    PARAGRAPH = :PARAGRAPH
 17    VERBATIM  = :VERBATIM
 18    
 19    # line type
 20    attr_accessor :type
 21
 22    # The indentation nesting level
 23    attr_accessor :level
 24
 25    # The contents
 26    attr_accessor :text
 27
 28    # A prefix or parameter. For LIST lines, this is
 29    # the text that introduced the list item (the label)
 30    attr_accessor  :param
 31
 32    # A flag. For list lines, this is the type of the list
 33    attr_accessor :flag
 34
 35    # the number of leading spaces
 36    attr_accessor :leading_spaces
 37
 38    # true if this line has been deleted from the list of lines
 39    attr_accessor :deleted
 40    
 41
 42    def initialize(text)
 43      @text    = text.dup
 44      @deleted = false
 45
 46      # expand tabs
 47      1 while @text.gsub!(/\t+/) { ' ' * (8*$&.length - $`.length % 8)}  && $~ #`
 48
 49      # Strip trailing whitespace
 50      @text.sub!(/\s+$/, '')
 51
 52      # and look for leading whitespace
 53      if @text.length > 0
 54        @text =~ /^(\s*)/
 55        @leading_spaces = $1.length
 56      else
 57        @leading_spaces = INFINITY
 58      end
 59    end
 60
 61    # Return true if this line is blank
 62    def isBlank?
 63      @text.length.zero?
 64    end
 65
 66    # stamp a line with a type, a level, a prefix, and a flag
 67    def stamp(type, level, param="", flag=nil)
 68      @type, @level, @param, @flag = type, level, param, flag
 69    end
 70
 71    ##
 72    # Strip off the leading margin
 73    #
 74
 75    def strip_leading(size)
 76      if @text.size > size
 77        @text[0,size] = ""
 78      else
 79        @text = ""
 80      end
 81    end
 82
 83    def to_s
 84      "#@type#@level: #@text"
 85    end
 86  end
 87
 88  ###############################################################################
 89  #
 90  # A container for all the lines
 91  #
 92
 93  class Lines
 94    include Enumerable
 95
 96    attr_reader :lines   # for debugging
 97
 98    def initialize(lines)
 99      @lines = lines
100      rewind
101    end
102
103    def empty?
104      @lines.size.zero?
105    end
106
107    def each
108      @lines.each do |line|
109        yield line unless line.deleted
110      end
111    end
112
113#    def [](index)
114#      @lines[index]
115#    end
116
117    def rewind
118      @nextline = 0
119    end
120
121    def next
122      begin
123        res = @lines[@nextline]
124        @nextline += 1 if @nextline < @lines.size
125      end while res and res.deleted and @nextline < @lines.size
126      res
127    end
128
129    def unget
130      @nextline -= 1
131    end
132
133    def delete(a_line)
134      a_line.deleted = true
135    end
136
137    def normalize
138      margin = @lines.collect{|l| l.leading_spaces}.min
139      margin = 0 if margin == Line::INFINITY
140      @lines.each {|line| line.strip_leading(margin) } if margin > 0
141    end
142
143    def as_text
144      @lines.map {|l| l.text}.join("\n")
145    end
146
147    def line_types
148      @lines.map {|l| l.type }
149    end
150  end
151end