Constructor. Any inheritors of this class should call super to make sure
this method is called.
parent
if supplied, the parent of this child will be set to the supplied value,
and self will be added to the parent
# File lib/rexml/child.rb, line 18
def initialize( parent = nil )
@parent = nil
# Declare @parent, but don't define it. The next line sets the
# parent.
parent.add( self ) if parent
end