class Opal::Nodes::StringNode

def to_utf16(code_point)
  ten_bits = 0b1111111111
  u = ->(code_unit) { '\\u' + code_unit.to_s(16).upcase }
  return u.call(code_point) if code_point <= 0xFFFF
  code_point -= 0x10000
  # Shift right to get to most significant 10 bits
  lead_surrogate = 0xD800 + (code_point >> 10)
  # Mask to get least significant 10 bits
  tail_surrogate = 0xDC00 + (code_point & ten_bits)
  u.call(lead_surrogate) + u.call(tail_surrogate)
end