Module: REXML::Functions (Ruby 2.3.4)

Home Classes Methods

In Files

rexml/functions.rb
rexml/parsers/xpathparser.rb
rexml/quickpath.rb
rexml/xpath_parser.rb

Methods

::boolean
::ceiling
::compare_language
::concat
::contains
::context=
::count
::false
::floor
::get_namespace
::id
::lang
::last
::local_name
::method_missing
::name
::namespace_context
::namespace_context=
::namespace_uri
::normalize_space
::not
::number
::position
::processing_instruction
::round
::starts_with
::string
::string_length
::string_value
::substring
::substring_after
::substring_before
::sum
::text
::translate
::true
::variables
::variables=

Class/Module Index

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 )

UNTESTED

 
               # File rexml/functions.rb, line 278
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 )

 
               # File rexml/functions.rb, line 374
def Functions::ceiling( number )
  number(number).ceil
end

compare_language(lang1, lang2)

 
               # File rexml/functions.rb, line 325
def Functions::compare_language lang1, lang2
  lang2.downcase.index(lang1.downcase) == 0
end

concat( *objects )

UNTESTED

 
               # File rexml/functions.rb, line 153
def Functions::concat( *objects )
  objects.join
end

contains( string, test )

Fixed by Mike Stok

 
               # File rexml/functions.rb, line 163
def Functions::contains( string, test )
  string(string).include?(string(test))
end

context=(value)

 
               # File rexml/functions.rb, line 20
def Functions::context=(value); @@context = value; end

count( node_set )

Returns the size of the given list of nodes.

 
               # File rexml/functions.rb, line 42
def Functions::count( node_set )
  node_set.size
end

false( )

UNTESTED

 
               # File rexml/functions.rb, line 302
def Functions::false(  )
  false
end

floor( number )

 
               # File rexml/functions.rb, line 370
def Functions::floor( number )
  number(number).floor
end

get_namespace( node_set = nil )

Helper method.

 
               # File rexml/functions.rb, line 69
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 )

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

 
               # File rexml/functions.rb, line 48
def Functions::id( object )
end

lang( language )

UNTESTED

 
               # File rexml/functions.rb, line 307
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( )

Returns the last node of the given list of nodes.

 
               # File rexml/functions.rb, line 33
def Functions::last( )
  @@context[:size]
end

local_name( node_set=nil )

UNTESTED

 
               # File rexml/functions.rb, line 52
def Functions::local_name( node_set=nil )
  get_namespace( node_set ) do |node|
    return node.local_name
  end
end

method_missing( id )

 
               # File rexml/functions.rb, line 390
def Functions::method_missing( id )
  puts "METHOD MISSING #{id.id2name}"
  XPath.match( @@context[:node], id.id2name )
end

name( node_set=nil )

 
               # File rexml/functions.rb, line 62
def Functions::name( node_set=nil )
  get_namespace( node_set ) do |node|
    node.expanded_name
  end
end

namespace_context()

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

namespace_context=(x)

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

namespace_uri( node_set=nil )

 
               # File rexml/functions.rb, line 58
def Functions::namespace_uri( node_set=nil )
  get_namespace( node_set ) {|node| node.namespace}
end

normalize_space( string=nil )

UNTESTED

 
               # File rexml/functions.rb, line 225
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 )

UNTESTED

 
               # File rexml/functions.rb, line 292
def Functions::not( object )
  not boolean( object )
end

number( object=nil )

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 342
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( )

 
               # File rexml/functions.rb, line 37
def Functions::position( )
  @@context[:index]
end

processing_instruction( node )

 
               # File rexml/functions.rb, line 386
def Functions::processing_instruction( node )
  node.node_type == :processing_instruction
end

round( number )

 
               # File rexml/functions.rb, line 378
def Functions::round( number )
  begin
    number(number).round
  rescue FloatDomainError
    number(number)
  end
end

starts_with( string, test )

Fixed by Mike Stok

 
               # File rexml/functions.rb, line 158
def Functions::starts_with( string, test )
  string(string).index(string(test)) == 0
end

string( object=nil )

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 116
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 )

UNTESTED

 
               # File rexml/functions.rb, line 220
def Functions::string_length( string )
  string(string).length
end

string_value( o )

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 140
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 )

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 187
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 )

Kouhei fixed this too

 
               # File rexml/functions.rb, line 179
def Functions::substring_after( string, test )
  ruby_string = string(string)
  return $1 if ruby_string =~ /#{test}(.*)/
  ""
end

substring_before( string, test )

Kouhei fixed this

 
               # File rexml/functions.rb, line 168
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 )

 
               # File rexml/functions.rb, line 365
def Functions::sum( nodes )
  nodes = [nodes] unless nodes.kind_of? Array
  nodes.inject(0) { |r,n| r + number(string(n)) }
end

text( )

 
               # File rexml/functions.rb, line 22
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 )

This is entirely Mike Stok’s beast

 
               # File rexml/functions.rb, line 235
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( )

UNTESTED

 
               # File rexml/functions.rb, line 297
def Functions::true( )
  true
end

variables()

 
               # File rexml/functions.rb, line 18
def Functions::variables ; @@variables ; end

variables=(x)

 
               # File rexml/functions.rb, line 16
def Functions::variables=(x) ; @@variables=x ; end