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               # File rexml/parsers/sax2parser.rb, line 25
def add_listener( listener )
  @parser.add_listener( listener )
end
             
             
               # File rexml/parsers/sax2parser.rb, line 77
def deafen( listener=nil, &blok )
  if listener
    @listeners.delete_if {|item| item[-1] == listener }
    @has_listeners = false if @listeners.size == 0
  else
    @procs.delete_if {|item| item[-1] == blok }
  end
end
             
            Listen arguments:
Listen to Symbol events on Array elements
Symbol, Block
Listen to Symbol events
Array, Listener
Listen to all events on Array elements
Array, Block
Listen to :start_element events on Array elements
Listener
Listen to All events
Symbol can be one of: :start_element, :end_element, :start_prefix_mapping, :end_prefix_mapping, :characters, :processing_instruction, :doctype, :attlistdecl, :elementdecl, :entitydecl, :notationdecl, :cdata, :xmldecl, :comment
There is an additional symbol that can be listened for: :progress. This will be called for every event generated, passing in the current stream position.
Array contains regular expressions or strings which will be matched against fully qualified element names.
Listener must implement the methods in SAX2Listener
Block will be passed the same arguments as a SAX2Listener method would be, where the method name is the same as the matched Symbol. See the SAX2Listener for more information.
 
               # File rexml/parsers/sax2parser.rb, line 59
def listen( *args, &blok )
  if args[0].kind_of? Symbol
    if args.size == 2
      args[1].each { |match| @procs << [args[0], match, blok] }
    else
      add( [args[0], nil, blok] )
    end
  elsif args[0].kind_of? Array
    if args.size == 2
      args[0].each { |match| add( [nil, match, args[1]] ) }
    else
      args[0].each { |match| add( [ :start_element, match, blok ] ) }
    end
  else
    add([nil, nil, args[0]])
  end
end
             
             
               # File rexml/parsers/sax2parser.rb, line 86
def parse
  @procs.each { |sym,match,block| block.call if sym == :start_document }
  @listeners.each { |sym,match,block|
    block.start_document if sym == :start_document or sym.nil?
  }
  context = []
  while true
    event = @parser.pull
    case event[0]
    when :end_document
      handle( :end_document )
      break
    when :start_doctype
      handle( :doctype, *event[1..-1])
    when :end_doctype
      context = context[1]
    when :start_element
      @tag_stack.push(event[1])
      # find the observers for namespaces
      procs = get_procs( :start_prefix_mapping, event[1] )
      listeners = get_listeners( :start_prefix_mapping, event[1] )
      if procs or listeners
        # break out the namespace declarations
        # The attributes live in event[2]
        event[2].each {|n, v| event[2][n] = @parser.normalize(v)}
        nsdecl = event[2].find_all { |n, value| n =~ /^xmlns(:|$)/ }
        nsdecl.collect! { |n, value| [ n[6..-1], value ] }
        @namespace_stack.push({})
        nsdecl.each do |n,v|
          @namespace_stack[-1][n] = v
          # notify observers of namespaces
          procs.each { |ob| ob.call( n, v ) } if procs
          listeners.each { |ob| ob.start_prefix_mapping(n, v) } if listeners
        end
      end
      event[1] =~ Namespace::NAMESPLIT
      prefix = $1
      local = $2
      uri = get_namespace(prefix)
      # find the observers for start_element
      procs = get_procs( :start_element, event[1] )
      listeners = get_listeners( :start_element, event[1] )
      # notify observers
      procs.each { |ob| ob.call( uri, local, event[1], event[2] ) } if procs
      listeners.each { |ob|
        ob.start_element( uri, local, event[1], event[2] )
      } if listeners
    when :end_element
      @tag_stack.pop
      event[1] =~ Namespace::NAMESPLIT
      prefix = $1
      local = $2
      uri = get_namespace(prefix)
      # find the observers for start_element
      procs = get_procs( :end_element, event[1] )
      listeners = get_listeners( :end_element, event[1] )
      # notify observers
      procs.each { |ob| ob.call( uri, local, event[1] ) } if procs
      listeners.each { |ob|
        ob.end_element( uri, local, event[1] )
      } if listeners
      namespace_mapping = @namespace_stack.pop
      # find the observers for namespaces
      procs = get_procs( :end_prefix_mapping, event[1] )
      listeners = get_listeners( :end_prefix_mapping, event[1] )
      if procs or listeners
        namespace_mapping.each do |ns_prefix, ns_uri|
          # notify observers of namespaces
          procs.each { |ob| ob.call( ns_prefix ) } if procs
          listeners.each { |ob| ob.end_prefix_mapping(ns_prefix) } if listeners
        end
      end
    when :text
      #normalized = @parser.normalize( event[1] )
      #handle( :characters, normalized )
      copy = event[1].clone
      esub = proc { |match|
        if @entities.has_key?($1)
          @entities[$1].gsub(Text::REFERENCE, &esub)
        else
          match
        end
      }
      copy.gsub!( Text::REFERENCE, &esub )
      copy.gsub!( Text::NUMERICENTITY ) {|m|
        m=$1
        m = "0#{m}" if m[0] == ?x
        [Integer(m)].pack('U*')
      }
      handle( :characters, copy )
    when :entitydecl
      handle_entitydecl( event )
    when :processing_instruction, :comment, :attlistdecl,
      :elementdecl, :cdata, :notationdecl, :xmldecl
      handle( *event )
    end
    handle( :progress, @parser.position )
  end
end