class Sass::Media::Query

def merge(other)
  m1, t1 = resolved_modifier.downcase, resolved_type.downcase
  m2, t2 = other.resolved_modifier.downcase, other.resolved_type.downcase
  t1 = t2 if t1.empty?
  t2 = t1 if t2.empty?
  if (m1 == 'not') ^ (m2 == 'not')
    return if t1 == t2
    type = m1 == 'not' ? t2 : t1
    mod = m1 == 'not' ? m2 : m1
  elsif m1 == 'not' && m2 == 'not'
    # CSS has no way of representing "neither screen nor print"
    return unless t1 == t2
    type = t1
    mod = 'not'
  elsif t1 != t2
    return
  else # t1 == t2, neither m1 nor m2 are "not"
    type = t1
    mod = m1.empty? ? m2 : m1
  end
  Query.new([mod], [type], other.expressions + expressions)
end