case '!':
			tok = s.switch2(token.NOT, token.NEQ)
		case '&':
			if s.ch == '^' {
				s.next()
				tok = s.switch2(token.AND_NOT, token.AND_NOT_ASSIGN)
			} else {
				tok = s.switch3(token.AND, token.AND_ASSIGN, '&', token.LAND)
			}
		case '|':
			tok = s.switch3(token.OR, token.OR_ASSIGN, '|', token.LOR)
		case '~':
			tok = token.TILDE
		default:
			// next reports unexpected BOMs - don't repeat

	{token.ADD_ASSIGN, "+=", operator},
	{token.SUB_ASSIGN, "-=", operator},
	{token.MUL_ASSIGN, "*=", operator},
	{token.QUO_ASSIGN, "/=", operator},
	{token.REM_ASSIGN, "%=", operator},

	{token.AND_ASSIGN, "&=", operator},
	{token.OR_ASSIGN, "|=", operator},
	{token.XOR_ASSIGN, "^=", operator},
	{token.SHL_ASSIGN, "<<=", operator},
	{token.SHR_ASSIGN, ">>=", operator},
	{token.AND_NOT_ASSIGN, "&^=", operator},