模块 REXML::Functions
如果您添加一个方法,请记住两件事:(1) 第一个参数始终是要从中筛选的节点列表。对于上下文方法(例如 position),该函数应返回一个数组,其中包含数组中每个子项的值。(2) 来自 XML 的所有方法调用都将用“_”替换“-”。因此,在 XML 中,“local-name()”与“local_name()”相同(实际上变成了“local_name()”)
常量
- INTERNAL_METHODS
- namespace_context
- variables
公共类方法
# File rexml-3.4.0/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
# File rexml-3.4.0/lib/rexml/functions.rb, line 417 def Functions::ceiling( number ) number(number).ceil end
# File rexml-3.4.0/lib/rexml/functions.rb, line 370 def Functions::compare_language lang1, lang2 lang2.downcase.index(lang1.downcase) == 0 end
# File rexml-3.4.0/lib/rexml/functions.rb, line 190 def Functions::concat( *objects ) concatenated = "" objects.each do |object| concatenated << string(object) end concatenated end
由 Mike Stok 修复
# File rexml-3.4.0/lib/rexml/functions.rb, line 204 def Functions::contains( string, test ) string(string).include?(string(test)) end
# File rexml-3.4.0/lib/rexml/functions.rb, line 38 def Functions::context=(value); @@context = value; end
返回给定节点列表的大小。
# File rexml-3.4.0/lib/rexml/functions.rb, line 60 def Functions::count( node_set ) node_set.size end
未测试
# File rexml-3.4.0/lib/rexml/functions.rb, line 347 def Functions::false( ) false end
# File rexml-3.4.0/lib/rexml/functions.rb, line 413 def Functions::floor( number ) number(number).floor end
辅助方法。
# File rexml-3.4.0/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
未测试
# File rexml-3.4.0/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
返回给定节点列表的最后一个节点。
# File rexml-3.4.0/lib/rexml/functions.rb, line 51 def Functions::last( ) @@context[:size] end
# File rexml-3.4.0/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
# File rexml-3.4.0/lib/rexml/functions.rb, line 80 def Functions::name( node_set=nil ) get_namespace( node_set ) do |node| node.expanded_name end end
# File rexml-3.4.0/lib/rexml/functions.rb, line 35 def Functions::namespace_context ; @@namespace_context ; end
# File rexml-3.4.0/lib/rexml/functions.rb, line 33 def Functions::namespace_context=(x) ; @@namespace_context=x ; end
# File rexml-3.4.0/lib/rexml/functions.rb, line 76 def Functions::namespace_uri( node_set=nil ) get_namespace( node_set ) {|node| node.namespace} end
# File rexml-3.4.0/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
未测试
# File rexml-3.4.0/lib/rexml/functions.rb, line 337 def Functions::not( object ) not boolean( object ) end
由可选的空白符、后跟可选的减号、后跟一个数字、后跟空白符组成的字符串被转换为最接近(根据 IEEE 754 四舍五入到最近规则)该字符串表示的数学值的 IEEE 754 数字;任何其他字符串都被转换为 NaN
布尔值 true 被转换为 1;布尔值 false 被转换为 0
节点集首先通过调用 string 函数转换为字符串,然后以与字符串参数相同的方式转换
其他四种基本类型以外的类型的对象以依赖于该类型的方式转换为数字
# File rexml-3.4.0/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
# File rexml-3.4.0/lib/rexml/functions.rb, line 55 def Functions::position( ) @@context[:index] end
# File rexml-3.4.0/lib/rexml/functions.rb, line 432 def Functions::processing_instruction( node ) node.node_type == :processing_instruction end
# File rexml-3.4.0/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
# File rexml-3.4.0/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
# File rexml-3.4.0/lib/rexml/functions.rb, line 26 def singleton_method_added(name) unless INTERNAL_METHODS.include?(name) @@available_functions[name] = true end end
由 Mike Stok 修复
# File rexml-3.4.0/lib/rexml/functions.rb, line 199 def Functions::starts_with( string, test ) string(string).index(string(test)) == 0 end
通过返回文档顺序中第一个节点集中节点的字符串值,将节点集转换为字符串。如果节点集为空,则返回一个空字符串。
数字按如下方式转换为字符串
NaN 被转换为字符串 NaN
正零被转换为字符串 0
负零被转换为字符串 0
正无穷大被转换为字符串 Infinity
负无穷大被转换为字符串 -Infinity
如果该数字是整数,则该数字以十进制形式表示为没有小数点且没有前导零的数字,如果该数字为负数,则在其前面加上减号 (-)
否则,该数字以十进制形式表示为数字,包括小数点,小数点前至少有一位数字,小数点后至少有一位数字,如果该数字为负数,则在其前面加上减号 (-); 小数点之前除了紧接小数点之前所需的数字之外,不能有前导零; 在小数点后所需的一个数字之外,必须有尽可能多的数字,但只能有足够多的数字,以将该数字与所有其他 IEEE 754 数值唯一区分开来。
布尔值 false 被转换为字符串 false。布尔值 true 被转换为字符串 true。
其他四种基本类型以外的类型的对象以依赖于该类型的方式转换为字符串。
# File rexml-3.4.0/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
未测试
# File rexml-3.4.0/lib/rexml/functions.rb, line 261 def Functions::string_length( string ) string(string).length end
通过返回文档顺序中第一个节点集中节点的每个子节点的字符串值的串联,将节点集转换为字符串。如果节点集为空,则返回一个空字符串。
# File rexml-3.4.0/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
取 Mike Stok 和 Sean Russell 的相等份量;用力混合,倒入一个高高的冰镇玻璃杯中。服务 10,000 人。
# File rexml-3.4.0/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
Kouhei 也修复了这个
# File rexml-3.4.0/lib/rexml/functions.rb, line 220 def Functions::substring_after( string, test ) ruby_string = string(string) return $1 if ruby_string =~ /#{test}(.*)/ "" end
Kouhei 修复了这个
# File rexml-3.4.0/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
# File rexml-3.4.0/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
# File rexml-3.4.0/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
这完全是 Mike Stok 的杰作
# File rexml-3.4.0/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
未测试
# File rexml-3.4.0/lib/rexml/functions.rb, line 342 def Functions::true( ) true end
# File rexml-3.4.0/lib/rexml/functions.rb, line 36 def Functions::variables ; @@variables ; end
# File rexml-3.4.0/lib/rexml/functions.rb, line 34 def Functions::variables=(x) ; @@variables=x ; end