module REXML::Functions

If you add a method, keep in mind two things: (1) the first argument will always be a list of nodes from which to filter. In the case of context methods (such as position), the function should return an array with a value for each child in the array. (2) all method calls from XML will have “-” replaced with “_”. Therefore, in XML, “local-name()” is identical (and actually becomes) “local_name()”

Constants

INTERNAL_METHODS
namespace_context
variables

Public Class Methods

boolean(object=@@context[:node]) click to toggle source
# File lib/rexml/functions.rb, line 317
def Functions::boolean(object=@@context[:node])
  case object
  when true, false
    object
  when Float
    return false if object.zero?
    return false if object.nan?
    true
  when Numeric
    not object.zero?
  when String
    not object.empty?
  when Array
    not object.empty?
  else
    object ? true : false
  end
end
ceiling( number ) click to toggle source
# File lib/rexml/functions.rb, line 417
def Functions::ceiling( number )
  number(number).ceil
end
compare_language(lang1, lang2) click to toggle source
# File lib/rexml/functions.rb, line 370
def Functions::compare_language lang1, lang2
  lang2.downcase.index(lang1.downcase) == 0
end
concat( *objects ) click to toggle source
# File lib/rexml/functions.rb, line 190
def Functions::concat( *objects )
  concatenated = ""
  objects.each do |object|
    concatenated << string(object)
  end
  concatenated
end
contains( string, test ) click to toggle source

Fixed by Mike Stok

# File lib/rexml/functions.rb, line 204
def Functions::contains( string, test )
  string(string).include?(string(test))
end
context=(value) click to toggle source
# File lib/rexml/functions.rb, line 38
def Functions::context=(value); @@context = value; end
count( node_set ) click to toggle source

Returns the size of the given list of nodes.

# File lib/rexml/functions.rb, line 60
def Functions::count( node_set )
  node_set.size
end
false( ) click to toggle source

UNTESTED

# File lib/rexml/functions.rb, line 347
def Functions::false(  )
  false
end
floor( number ) click to toggle source
# File lib/rexml/functions.rb, line 413
def Functions::floor( number )
  number(number).floor
end
get_namespace( node_set = nil ) { |context| ... } click to toggle source

Helper method.

# File lib/rexml/functions.rb, line 87
def Functions::get_namespace( node_set = nil )
  if node_set == nil
    yield @@context[:node] if @@context[:node].respond_to?(:namespace)
  else
    if node_set.respond_to? :each
      result = []
      node_set.each do |node|
        result << yield(node) if node.respond_to?(:namespace)
      end
      result
    elsif node_set.respond_to? :namespace
      yield node_set
    end
  end
end
id( object ) click to toggle source

Since REXML is non-validating, this method is not implemented as it requires a DTD

# File lib/rexml/functions.rb, line 66
def Functions::id( object )
end
lang( language ) click to toggle source

UNTESTED

# File lib/rexml/functions.rb, line 352
def Functions::lang( language )
  lang = false
  node = @@context[:node]
  attr = nil
  until node.nil?
    if node.node_type == :element
      attr = node.attributes["xml:lang"]
      unless attr.nil?
        lang = compare_language(string(language), attr)
        break
      else
      end
    end
    node = node.parent
  end
  lang
end
last( ) click to toggle source

Returns the last node of the given list of nodes.

# File lib/rexml/functions.rb, line 51
def Functions::last( )
  @@context[:size]
end
local_name(node_set=nil) click to toggle source
# File lib/rexml/functions.rb, line 69
def Functions::local_name(node_set=nil)
  get_namespace(node_set) do |node|
    return node.local_name
  end
  ""
end
name( node_set=nil ) click to toggle source
# File lib/rexml/functions.rb, line 80
def Functions::name( node_set=nil )
  get_namespace( node_set ) do |node|
    node.expanded_name
  end
end
namespace_context() click to toggle source
# File lib/rexml/functions.rb, line 35
def Functions::namespace_context ; @@namespace_context ; end
namespace_context=(x) click to toggle source
# File lib/rexml/functions.rb, line 33
def Functions::namespace_context=(x) ; @@namespace_context=x ; end
namespace_uri( node_set=nil ) click to toggle source
# File lib/rexml/functions.rb, line 76
def Functions::namespace_uri( node_set=nil )
  get_namespace( node_set ) {|node| node.namespace}
end
normalize_space( string=nil ) click to toggle source
# File lib/rexml/functions.rb, line 265
def Functions::normalize_space( string=nil )
  string = string(@@context[:node]) if string.nil?
  if string.kind_of? Array
    string.collect{|x| x.to_s.strip.gsub(/\s+/um, ' ') if x}
  else
    string.to_s.strip.gsub(/\s+/um, ' ')
  end
end
not( object ) click to toggle source

UNTESTED

# File lib/rexml/functions.rb, line 337
def Functions::not( object )
  not boolean( object )
end
number(object=@@context[:node]) click to toggle source

a string that consists of optional whitespace followed by an optional minus sign followed by a Number followed by whitespace is converted to the IEEE 754 number that is nearest (according to the IEEE 754 round-to-nearest rule) to the mathematical value represented by the string; any other string is converted to NaN

boolean true is converted to 1; boolean false is converted to 0

a node-set is first converted to a string as if by a call to the string function and then converted in the same way as a string argument

an object of a type other than the four basic types is converted to a number in a way that is dependent on that type

# File lib/rexml/functions.rb, line 387
def Functions::number(object=@@context[:node])
  case object
  when true
    Float(1)
  when false
    Float(0)
  when Array
    number(string(object))
  when Numeric
    object.to_f
  else
    str = string(object)
    case str.strip
    when /\A\s*(-?(?:\d+(?:\.\d*)?|\.\d+))\s*\z/
      $1.to_f
    else
      Float::NAN
    end
  end
end
position( ) click to toggle source
# File lib/rexml/functions.rb, line 55
def Functions::position( )
  @@context[:index]
end
processing_instruction( node ) click to toggle source
# File lib/rexml/functions.rb, line 432
def Functions::processing_instruction( node )
  node.node_type == :processing_instruction
end
round( number ) click to toggle source
# File lib/rexml/functions.rb, line 421
def Functions::round( number )
  number = number(number)
  begin
    neg = number.negative?
    number = number.abs.round
    neg ? -number : number
  rescue FloatDomainError
    number
  end
end
send(name, *args) click to toggle source
Calls superclass method
# File lib/rexml/functions.rb, line 436
def Functions::send(name, *args)
  if @@available_functions[name.to_sym]
    super
  else
    # TODO: Maybe, this is not XPath spec behavior.
    # This behavior must be reconsidered.
    XPath.match(@@context[:node], name.to_s)
  end
end
singleton_method_added(name) click to toggle source
# File lib/rexml/functions.rb, line 26
def singleton_method_added(name)
  unless INTERNAL_METHODS.include?(name)
    @@available_functions[name] = true
  end
end
starts_with( string, test ) click to toggle source

Fixed by Mike Stok

# File lib/rexml/functions.rb, line 199
def Functions::starts_with( string, test )
  string(string).index(string(test)) == 0
end
string( object=@@context[:node] ) click to toggle source

A node-set is converted to a string by returning the string-value of the node in the node-set that is first in document order. If the node-set is empty, an empty string is returned.

A number is converted to a string as follows

NaN is converted to the string NaN

positive zero is converted to the string 0

negative zero is converted to the string 0

positive infinity is converted to the string Infinity

negative infinity is converted to the string -Infinity

if the number is an integer, the number is represented in decimal form as a Number with no decimal point and no leading zeros, preceded by a minus sign (-) if the number is negative

otherwise, the number is represented in decimal form as a Number including a decimal point with at least one digit before the decimal point and at least one digit after the decimal point, preceded by a minus sign (-) if the number is negative; there must be no leading zeros before the decimal point apart possibly from the one required digit immediately before the decimal point; beyond the one required digit after the decimal point there must be as many, but only as many, more digits as are needed to uniquely distinguish the number from all other IEEE 754 numeric values.

The boolean false value is converted to the string false. The boolean true value is converted to the string true.

An object of a type other than the four basic types is converted to a string in a way that is dependent on that type.

# File lib/rexml/functions.rb, line 138
def Functions::string( object=@@context[:node] )
  if object.respond_to?(:node_type)
    case object.node_type
    when :attribute
      object.value
    when :element
      string_value(object)
    when :document
      string_value(object.root)
    when :processing_instruction
      object.content
    else
      object.to_s
    end
  else
    case object
    when Array
      string(object[0])
    when Float
      if object.nan?
        "NaN"
      else
        integer = object.to_i
        if object == integer
          "%d" % integer
        else
          object.to_s
        end
      end
    else
      object.to_s
    end
  end
end
string_length( string ) click to toggle source

UNTESTED

# File lib/rexml/functions.rb, line 261
def Functions::string_length( string )
  string(string).length
end
string_value( o ) click to toggle source

A node-set is converted to a string by returning the concatenation of the string-value of each of the children of the node in the node-set that is first in document order. If the node-set is empty, an empty string is returned.

# File lib/rexml/functions.rb, line 178
def Functions::string_value( o )
  rv = ""
  o.children.each { |e|
    if e.node_type == :text
      rv << e.to_s
    elsif e.node_type == :element
      rv << string_value( e )
    end
  }
  rv
end
substring( string, start, length=nil ) click to toggle source

Take equal portions of Mike Stok and Sean Russell; mix vigorously, and pour into a tall, chilled glass. Serves 10,000.

# File lib/rexml/functions.rb, line 228
def Functions::substring( string, start, length=nil )
  ruby_string = string(string)
  ruby_length = if length.nil?
                  ruby_string.length.to_f
                else
                  number(length)
                end
  ruby_start = number(start)

  # Handle the special cases
  return '' if (
    ruby_length.nan? or
    ruby_start.nan? or
    ruby_start.infinite?
  )

  infinite_length = ruby_length.infinite? == 1
  ruby_length = ruby_string.length if infinite_length

  # Now, get the bounds.  The XPath bounds are 1..length; the ruby bounds
  # are 0..length.  Therefore, we have to offset the bounds by one.
  ruby_start = round(ruby_start) - 1
  ruby_length = round(ruby_length)

  if ruby_start < 0
   ruby_length += ruby_start unless infinite_length
   ruby_start = 0
  end
  return '' if ruby_length <= 0
  ruby_string[ruby_start,ruby_length]
end
substring_after( string, test ) click to toggle source

Kouhei fixed this too

# File lib/rexml/functions.rb, line 220
def Functions::substring_after( string, test )
  ruby_string = string(string)
  return $1 if ruby_string =~ /#{test}(.*)/
  ""
end
substring_before( string, test ) click to toggle source

Kouhei fixed this

# File lib/rexml/functions.rb, line 209
def Functions::substring_before( string, test )
  ruby_string = string(string)
  ruby_index = ruby_string.index(string(test))
  if ruby_index.nil?
    ""
  else
    ruby_string[ 0...ruby_index ]
  end
end
sum( nodes ) click to toggle source
# File lib/rexml/functions.rb, line 408
def Functions::sum( nodes )
  nodes = [nodes] unless nodes.kind_of? Array
  nodes.inject(0) { |r,n| r + number(string(n)) }
end
text( ) click to toggle source
# File lib/rexml/functions.rb, line 40
def Functions::text( )
  if @@context[:node].node_type == :element
    return @@context[:node].find_all{|n| n.node_type == :text}.collect{|n| n.value}
  elsif @@context[:node].node_type == :text
    return @@context[:node].value
  else
    return false
  end
end
translate( string, tr1, tr2 ) click to toggle source

This is entirely Mike Stok’s beast

# File lib/rexml/functions.rb, line 275
def Functions::translate( string, tr1, tr2 )
  from = string(tr1)
  to = string(tr2)

  # the map is our translation table.
  #
  # if a character occurs more than once in the
  # from string then we ignore the second &
  # subsequent mappings
  #
  # if a character maps to nil then we delete it
  # in the output.  This happens if the from
  # string is longer than the to string
  #
  # there's nothing about - or ^ being special in
  # http://www.w3.org/TR/xpath#function-translate
  # so we don't build ranges or negated classes

  map = Hash.new
  0.upto(from.length - 1) { |pos|
    from_char = from[pos]
    unless map.has_key? from_char
      map[from_char] =
      if pos < to.length
        to[pos]
      else
        nil
      end
    end
  }

  if ''.respond_to? :chars
    string(string).chars.collect { |c|
      if map.has_key? c then map[c] else c end
    }.compact.join
  else
    string(string).unpack('U*').collect { |c|
      if map.has_key? c then map[c] else c end
    }.compact.pack('U*')
  end
end
true( ) click to toggle source

UNTESTED

# File lib/rexml/functions.rb, line 342
def Functions::true( )
  true
end
variables() click to toggle source
# File lib/rexml/functions.rb, line 36
def Functions::variables ; @@variables ; end
variables=(x) click to toggle source
# File lib/rexml/functions.rb, line 34
def Functions::variables=(x) ; @@variables=x ; end