#     assert -1u32 == 0xFFFFFFFFu32
	#     assert -0u32 == 0x00u32
	redef fun - is intern

	#     assert -1i8 == 0xFFi8
	#     assert -0i8 == 0x00i8
	redef fun - is intern

	#     assert -1i16 == 0xFFFFi16
	#     assert -0i16 == 0i16
	redef fun - is intern

	#     assert -1u16 == 0xFFFFu16
	#     assert -0u16 == 0u16
	redef fun - is intern

	#     assert -1i32 == 0xFFFFFFFFi32
	#     assert -0i32 == 0x00i32
	redef fun - is intern

    #     assert( -("1/2".to_r) == ("-1/2").to_r)
    redef fun - do
        var res = new NativeMPQ
        val.neg res
        return new Ratio(res)
    end

	# On an Byte, unary minus will return `(256 - self) % 256`
	#
	#     assert -1u8 == 0xFFu8
	#     assert -0u8 == 0x00u8
	redef fun - is intern

	redef fun - is intern

    #     assert(-(2.to_bi) == (-2).to_bi)
    redef fun - do
        var res = new NativeMPZ
        val.neg res
        return new BigInt(res)
    end

	redef fun - is intern