You don't want to use this class. Really. Use XPath, which is a wrapper for this class. Believe me. You don't want to poke around in here. There is strange, dark magic at work in this code. Beware. Go back! Go back while you still can!

Methods
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Included Modules
Constants
LITERAL = /^'([^']*)'|^"([^"]*)"/u
 
ALL = [ :attribute, :element, :text, :processing_instruction, :comment ]
 

Expr takes a stack of path elements and a set of nodes (either a Parent or an Array and returns an Array of matching nodes

ELEMENTS = [ :element ]
 
Class Public methods
new( )
# File lib/rexml/xpath_parser.rb, line 49
def initialize( )
  @parser = REXML::Parsers::XPathParser.new
  @namespaces = nil
  @variables = {}
end
Instance Public methods
[]=( variable_name, value )
# File lib/rexml/xpath_parser.rb, line 86
def []=( variable_name, value )
  @variables[ variable_name ] = value
end
first( path_stack, node )

Performs a depth-first (document order) XPath search, and returns the first match. This is the fastest, lightest way to return a single result.

FIXME: This method is incomplete!

# File lib/rexml/xpath_parser.rb, line 95
def first( path_stack, node )
  #puts "#{depth}) Entering match( #{path.inspect}, #{tree.inspect} )"
  return nil if path.size == 0

  case path[0]
  when :document
    # do nothing
    return first( path[1..-1], node )
  when :child
    for c in node.children
      #puts "#{depth}) CHILD checking #{name(c)}"
      r = first( path[1..-1], c )
      #puts "#{depth}) RETURNING #{r.inspect}" if r
      return r if r
    end
  when :qname
    name = path[2]
    #puts "#{depth}) QNAME #{name(tree)} == #{name} (path => #{path.size})"
    if node.name == name
      #puts "#{depth}) RETURNING #{tree.inspect}" if path.size == 3
      return node if path.size == 3
      return first( path[3..-1], node )
    else
      return nil
    end
  when :descendant_or_self
    r = first( path[1..-1], node )
    return r if r
    for c in node.children
      r = first( path, c )
      return r if r
    end
  when :node
    return first( path[1..-1], node )
  when :any
    return first( path[1..-1], node )
  end
  return nil
end
get_first(path, nodeset)
# File lib/rexml/xpath_parser.rb, line 73
def get_first path, nodeset
 #puts "#"*40
 path_stack = @parser.parse( path )
 #puts "PARSE: #{path} => #{path_stack.inspect}"
 #puts "PARSE: nodeset = #{nodeset.inspect}"
 first( path_stack, nodeset )
end
match( path_stack, nodeset )
# File lib/rexml/xpath_parser.rb, line 136
def match( path_stack, nodeset )
  #puts "MATCH: path_stack = #{path_stack.inspect}"
  #puts "MATCH: nodeset = #{nodeset.inspect}"
  r = expr( path_stack, nodeset )
  #puts "MAIN EXPR => #{r.inspect}"
  r
end
namespaces=( namespaces={} )
# File lib/rexml/xpath_parser.rb, line 55
def namespaces=( namespaces={} )
  Functions::namespace_context = namespaces
  @namespaces = namespaces
end
parse(path, nodeset)
# File lib/rexml/xpath_parser.rb, line 65
def parse path, nodeset
 #puts "#"*40
 path_stack = @parser.parse( path )
 #puts "PARSE: #{path} => #{path_stack.inspect}"
 #puts "PARSE: nodeset = #{nodeset.inspect}"
 match( path_stack, nodeset )
end
predicate(path, nodeset)
# File lib/rexml/xpath_parser.rb, line 81
def predicate path, nodeset
  path_stack = @parser.parse( path )
  expr( path_stack, nodeset )
end
variables=( vars={} )
# File lib/rexml/xpath_parser.rb, line 60
def variables=( vars={} )
  Functions::variables = vars
  @variables = vars
end