require "rexml/child" module REXML # A parent has children, and has methods for accessing them. The Parent # class is never encountered except as the superclass for some other # object. class Parent < Child include Enumerable # Constructor # @param parent if supplied, will be set as the parent of this object def initialize parent=nil super(parent) @children = [] end def add( object ) object.parent = self @children << object object end alias :push :add alias :<< :push def unshift( object ) object.parent = self @children.unshift object end def delete( object ) found = false @children.delete_if {|c| c.equal?(object) and found = true } object.parent = nil if found found ? object : nil end def each(&block) @children.each(&block) end def delete_if( &block ) @children.delete_if(&block) end def delete_at( index ) @children.delete_at index end def each_index( &block ) @children.each_index(&block) end # Fetches a child at a given index # @param index the Integer index of the child to fetch def []( index ) @children[index] end alias :each_child :each # Set an index entry. See Array.[]= # @param index the index of the element to set # @param opt either the object to set, or an Integer length # @param child if opt is an Integer, this is the child to set # @return the parent (self) def []=( *args ) args[-1].parent = self @children[*args[0..-2]] = args[-1] end # Inserts an child before another child # @param child1 this is either an xpath or an Element. If an Element, # child2 will be inserted before child1 in the child list of the parent. # If an xpath, child2 will be inserted before the first child to match # the xpath. # @param child2 the child to insert # @return the parent (self) def insert_before( child1, child2 ) if child1.kind_of? String child1 = XPath.first( self, child1 ) child1.parent.insert_before child1, child2 else ind = index(child1) child2.parent.delete(child2) if child2.parent @children[ind,0] = child2 child2.parent = self end self end # Inserts an child after another child # @param child1 this is either an xpath or an Element. If an Element, # child2 will be inserted after child1 in the child list of the parent. # If an xpath, child2 will be inserted after the first child to match # the xpath. # @param child2 the child to insert # @return the parent (self) def insert_after( child1, child2 ) if child1.kind_of? String child1 = XPath.first( self, child1 ) child1.parent.insert_after child1, child2 else ind = index(child1)+1 child2.parent.delete(child2) if child2.parent @children[ind,0] = child2 child2.parent = self end self end def to_a @children.dup end # Fetches the index of a given child # @param child the child to get the index of # @return the index of the child, or nil if the object is not a child # of this parent. def index( child ) count = -1 @children.find { |i| count += 1 ; i.hash == child.hash } count end # @return the number of children of this parent def size @children.size end alias :length :size # Replaces one child with another, making sure the nodelist is correct # @param to_replace the child to replace (must be a Child) # @param replacement the child to insert into the nodelist (must be a # Child) def replace_child( to_replace, replacement ) @children.map! {|c| c.equal?( to_replace ) ? replacement : c } to_replace.parent = nil replacement.parent = self end # Deeply clones this object. This creates a complete duplicate of this # Parent, including all descendants. def deep_clone cl = clone() each do |child| if child.kind_of? Parent cl << child.deep_clone else cl << child.clone end end cl end alias :children :to_a def parent? true end end end