equality_relational_compare

# File lib/rexml/xpath_parser.rb, line 803
    def equality_relational_compare( set1, op, set2 )
      set1 = unnode(set1) if set1.is_a?(Array)
      set2 = unnode(set2) if set2.is_a?(Array)
      if set1.kind_of? Array and set2.kind_of? Array
        if set1.size == 0 or set2.size == 0
          nd = set1.size==0 ? set2 : set1
          rv = nd.collect { |il| compare( il, op, nil ) }
          return rv
        else
          res = []
          SyncEnumerator.new( set1, set2 ).each { |i1, i2|
            i1 = norm( i1 )
            i2 = norm( i2 )
            res << compare( i1, op, i2 )
          }
          return res
        end
      end
      # If one is nodeset and other is number, compare number to each item
      # in nodeset s.t. number op number(string(item))
      # If one is nodeset and other is string, compare string to each item
      # in nodeset s.t. string op string(item)
      # If one is nodeset and other is boolean, compare boolean to each item
      # in nodeset s.t. boolean op boolean(item)
      if set1.kind_of? Array or set2.kind_of? Array
        if set1.kind_of? Array
          a = set1
          b = set2
        else
          a = set2
          b = set1
        end

        case b
        when true, false
          return unnode(a) {|v| compare( Functions::boolean(v), op, b ) }
        when Numeric
          return unnode(a) {|v| compare( Functions::number(v), op, b )}
        when /^\d+(\.\d+)?$/
          b = Functions::number( b )
          return unnode(a) {|v| compare( Functions::number(v), op, b )}
        else
          b = Functions::string( b )
          return unnode(a) { |v| compare( Functions::string(v), op, b ) }
        end
      else
        # If neither is nodeset,
        #   If op is = or !=
        #     If either boolean, convert to boolean
        #     If either number, convert to number
        #     Else, convert to string
        #   Else
        #     Convert both to numbers and compare
        set1 = unnode(set1) if set1.is_a?(Array)
        set2 = unnode(set2) if set2.is_a?(Array)
        s1 = Functions.string(set1)
        s2 = Functions.string(set2)
        if s1 == 'true' or s1 == 'false' or s2 == 'true' or s2 == 'false'
          set1 = Functions::boolean( set1 )
          set2 = Functions::boolean( set2 )
        else
          if op == :eq or op == :neq
            if s1 =~ /^\d+(\.\d+)?$/ or s2 =~ /^\d+(\.\d+)?$/
              set1 = Functions::number( s1 )
              set2 = Functions::number( s2 )
            else
              set1 = Functions::string( set1 )
              set2 = Functions::string( set2 )
            end
          else
            set1 = Functions::number( set1 )
            set2 = Functions::number( set2 )
          end
        end
        return compare( set1, op, set2 )
      end
      return false
    end