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()”

Public Class Methods

boolean( object=nil ) click to toggle source

UNTESTED

 
               # File rexml/functions.rb, line 277
def Functions::boolean( object=nil )
  if object.kind_of? String
    if object =~ /\d+/u
      return object.to_f != 0
    else
      return object.size > 0
    end
  elsif object.kind_of? Array
    object = object.find{|x| x and true}
  end
  return object ? true : false
end

ceiling( number ) click to toggle source

 
               # File rexml/functions.rb, line 373
def Functions::ceiling( number )
  number(number).ceil
end

compare_language(lang1, lang2) click to toggle source

 
               # File rexml/functions.rb, line 324
def Functions::compare_language lang1, lang2
  lang2.downcase.index(lang1.downcase) == 0
end

concat( *objects ) click to toggle source

UNTESTED

 
               # File rexml/functions.rb, line 152
def Functions::concat( *objects )
  objects.join
end

contains( string, test ) click to toggle source

Fixed by Mike Stok

 
               # File rexml/functions.rb, line 162
def Functions::contains( string, test )
  string(string).include?(string(test))
end

context=(value) click to toggle source

 
               # File rexml/functions.rb, line 19
def Functions::context=(value); @@context = value; end

count( node_set ) click to toggle source

Returns the size of the given list of nodes.

 
               # File rexml/functions.rb, line 41
def Functions::count( node_set )
  node_set.size
end

false( ) click to toggle source

UNTESTED

 
               # File rexml/functions.rb, line 301
def Functions::false(  )
  false
end

floor( number ) click to toggle source

 
               # File rexml/functions.rb, line 369
def Functions::floor( number )
  number(number).floor
end

get_namespace( node_set = nil ) click to toggle source

Helper method.

 
               # File rexml/functions.rb, line 68
def Functions::get_namespace( node_set = nil )
  if node_set == nil
    yield @@context[:node] if defined? @@context[:node].namespace
  else
    if node_set.respond_to? :each
      node_set.each { |node| yield node if defined? node.namespace }
    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 rexml/functions.rb, line 47
def Functions::id( object )
end

lang( language ) click to toggle source

UNTESTED

 
               # File rexml/functions.rb, line 306
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 rexml/functions.rb, line 32
def Functions::last( )
  @@context[:size]
end

local_name( node_set=nil ) click to toggle source

UNTESTED

 
               # File rexml/functions.rb, line 51
def Functions::local_name( node_set=nil )
  get_namespace( node_set ) do |node|
    return node.local_name
  end
end

method_missing( id ) click to toggle source

 
               # File rexml/functions.rb, line 389
def Functions::method_missing( id )
  puts "METHOD MISSING #{id.id2name}"
  XPath.match( @@context[:node], id.id2name )
end

name( node_set=nil ) click to toggle source

 
               # File rexml/functions.rb, line 61
def Functions::name( node_set=nil )
  get_namespace( node_set ) do |node|
    node.expanded_name
  end
end

namespace_context() click to toggle source

 
               # File rexml/functions.rb, line 16
def Functions::namespace_context ; @@namespace_context ; end

namespace_context=(x) click to toggle source

 
               # File rexml/functions.rb, line 14
def Functions::namespace_context=(x) ; @@namespace_context=x ; end

namespace_uri( node_set=nil ) click to toggle source

 
               # File rexml/functions.rb, line 57
def Functions::namespace_uri( node_set=nil )
  get_namespace( node_set ) {|node| node.namespace}
end

normalize_space( string=nil ) click to toggle source

UNTESTED

 
               # File rexml/functions.rb, line 224
def Functions::normalize_space( string=nil )
  string = string(@@context[:node]) if string.nil?
  if string.kind_of? Array
    string.collect{|x| string.to_s.strip.gsub(/\s+/um, ' ') if string}
  else
    string.to_s.strip.gsub(/\s+/um, ' ')
  end
end

not( object ) click to toggle source

UNTESTED

 
               # File rexml/functions.rb, line 291
def Functions::not( object )
  not boolean( object )
end

number( object=nil ) 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 rexml/functions.rb, line 341
def Functions::number( object=nil )
  object = @@context[:node] unless object
  case object
  when true
    Float(1)
  when false
    Float(0)
  when Array
    number(string( object ))
  when Numeric
    object.to_f
  else
    str = string( object )
    # If XPath ever gets scientific notation...
    #if str =~ /^\s*-?(\d*\.?\d+|\d+\.)([Ee]\d*)?\s*$/
    if str =~ /^\s*-?(\d*\.?\d+|\d+\.)\s*$/
      str.to_f
    else
      (0.0 / 0.0)
    end
  end
end

position( ) click to toggle source

 
               # File rexml/functions.rb, line 36
def Functions::position( )
  @@context[:index]
end

processing_instruction( node ) click to toggle source

 
               # File rexml/functions.rb, line 385
def Functions::processing_instruction( node )
  node.node_type == :processing_instruction
end

round( number ) click to toggle source

 
               # File rexml/functions.rb, line 377
def Functions::round( number )
  begin
    number(number).round
  rescue FloatDomainError
    number(number)
  end
end

starts_with( string, test ) click to toggle source

Fixed by Mike Stok

 
               # File rexml/functions.rb, line 157
def Functions::starts_with( string, test )
  string(string).index(string(test)) == 0
end

string( object=nil ) 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 rexml/functions.rb, line 115
def Functions::string( object=nil )
  #object = @context unless object
  if object.instance_of? Array
    string( object[0] )
  elsif defined? object.node_type
    if object.node_type == :attribute
      object.value
    elsif object.node_type == :element || object.node_type == :document
      string_value(object)
    else
      object.to_s
    end
  elsif object.nil?
    return ""
  else
    object.to_s
  end
end

string_length( string ) click to toggle source

UNTESTED

 
               # File rexml/functions.rb, line 219
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 rexml/functions.rb, line 139
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 rexml/functions.rb, line 186
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 = ruby_start.round - 1
  ruby_length = ruby_length.round

  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 rexml/functions.rb, line 178
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 rexml/functions.rb, line 167
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 rexml/functions.rb, line 364
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 rexml/functions.rb, line 21
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 rexml/functions.rb, line 234
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 rexml/functions.rb, line 296
def Functions::true( )
  true
end

variables() click to toggle source

 
               # File rexml/functions.rb, line 17
def Functions::variables ; @@variables ; end

variables=(x) click to toggle source

 
               # File rexml/functions.rb, line 15
def Functions::variables=(x) ; @@variables=x ; end

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