# File lib/diff/lcs.rb, line 923
923:     def __position_hash(enum, interval = 0 .. -1)
924:       hash = Hash.new { |hh, kk| hh[kk] = [] }
925:       interval.each do |ii|
926:         kk = enum.kind_of?(String) ? enum[ii, 1] : enum[ii]
927:         hash[kk] << ii
928:       end
929:       hash
930:     end