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In Files

  • rexml/formatters/pretty.rb

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Pretty-prints an XML document. This destroys whitespace in text nodes and will insert carriage returns and indentations.

TODO: Add an option to print attributes on new lines



If compact is set to true, then the formatter will attempt to use as little space as possible


The width of a page. Used for formatting text

Public Class Methods

new( indentation=2, ie_hack=false ) click to toggle source

Create a new pretty printer.


An object implementing ‘<<(String)’, to which the output will be written.


An integer greater than 0. The indentation of each level will be this number of spaces. If this is < 1, the behavior of this object is undefined. Defaults to 2.


If true, the printer will insert whitespace before closing empty tags, thereby allowing Internet Explorer’s feeble XML parser to function. Defaults to false.

               # File rexml/formatters/pretty.rb, line 29
def initialize( indentation=2, ie_hack=false )
  @indentation = indentation
  @level = 0
  @ie_hack = ie_hack
  @width = 80

Protected Instance Methods

write_cdata( node, output) click to toggle source
               # File rexml/formatters/pretty.rb, line 100
def write_cdata( node, output)
  output << ' ' * @level
write_comment( node, output) click to toggle source
               # File rexml/formatters/pretty.rb, line 95
def write_comment( node, output)
  output << ' ' * @level
write_document( node, output ) click to toggle source
               # File rexml/formatters/pretty.rb, line 105
def write_document( node, output )
  # Ok, this is a bit odd.  All XML documents have an XML declaration,
  # but it may not write itself if the user didn't specifically add it,
  # either through the API or in the input document.  If it doesn't write
  # itself, then we don't need a carriage return... which makes this
  # logic more complex.
  node.children.each { |child|
    next if child == node.children[-1] and child.instance_of?(Text)
    unless child == node.children[0] or child.instance_of?(Text) or
      (child == node.children[1] and !node.children[0].writethis)
      output << "\n"
    write( child, output )
write_element(node, output) click to toggle source
               # File rexml/formatters/pretty.rb, line 37
def write_element(node, output)
  output << ' '*@level
  output << "<#{node.expanded_name}"

  node.attributes.each_attribute do |attr|
    output << " "
    attr.write( output )
  end unless node.attributes.empty?

  if node.children.empty?
    if @ie_hack
      output << " "
    output << "/" 
    output << ">"
    # If compact and all children are text, and if the formatted output
    # is less than the specified width, then try to print everything on
    # one line
    skip = false
    if compact
      if node.children.inject(true) {|s,c| s & c.kind_of?(Text)}
        string = ""
        old_level = @level
        @level = 0
        node.children.each { |child| write( child, string ) }
        @level = old_level
        if string.length < @width
          output << string
          skip = true
    unless skip
      output << "\n"
      @level += @indentation
      node.children.each { |child|
        next if child.kind_of?(Text) and child.to_s.strip.length == 0
        write( child, output )
        output << "\n"
      @level -= @indentation
      output << ' '*@level
    output << "</#{node.expanded_name}"
  output << ">"
write_text( node, output ) click to toggle source
               # File rexml/formatters/pretty.rb, line 86
def write_text( node, output )
  s = node.to_s()
  s.gsub!(/\s/,' ')
  s.squeeze!(" ")
  s = wrap(s, 80-@level)
  s = indent_text(s, @level, " ", true)
  output << (' '*@level + s)

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