if not defined?(BTag)

  BTag = Binenc::BinTag.new 

  BTag.load do

    # hierarchy
    define_constant(:root, '2.8.8') do

      define_constant(:kdf, "#.10") do
        define_constant(:kdf_scrypt, "#.0")
        define_constant(:kdf_hkdf, "#.1")
        define_constant(:kdf_pbkdf2, "#.2")
      end

      define_constant(:digest, "#.20")
      define_constant(:digest_attached, "#.21")

      define_constant(:symkey, "#.30") do
        define_constant(:symkey_derived, "#.0")
        define_constant(:plain_symkey, "#.1")
        define_constant(:symkey_vtype_kdf, "#.2")

        define_constant(:symkey_cipher, "#.20")
        define_constant(:symkey_signature, "#.21")
        define_constant(:symkey_att_sign, "#.22")

        define_constant(:kcv, "#.30")
      end

      define_constant(:compression, "#.40") do
        define_constant(:compression_none, "#.0")
        define_constant(:compression_zlib, "#.1")
        define_constant(:compression_zlib_attached, "#.2")
      end

      define_constant(:asymkey, "#.50") do
        define_constant(:ecc, "#.1") do
          define_constant(:ecc_cipher, "#.10")
          define_constant(:ecc_signature, "#.11") do
            define_constant(:ecc_signer_info, "#.1")
          end

          define_constant(:ecc_att_sign, "#.12")
        end
      end

      define_constant(:composite, "#.60") do
        define_constant(:sign_encrypt_cipher, "#.1")
      end

      define_constant(:shared_secret, "#.70")

    end



    # constant
    define_constant(:sha1,         0x0101)
    define_constant(:sha256,       0x0102)
    define_constant(:sha384,       0x0103)
    define_constant(:sha224,       0x0104)
    define_constant(:sha512,       0x0105)
    define_constant(:sha512_224,   0x0106)
    define_constant(:sha512_256,   0x0107)

    define_constant(:sha3_256,     0x0110)
    define_constant(:sha3_224,     0x0111)
    define_constant(:sha3_384,     0x0112)
    define_constant(:sha3_512,     0x0113)

    define_constant(:shake128,     0x0120)
    define_constant(:shake256,     0x0121)

    define_constant(:blake2b160,   0x0130)
    define_constant(:blake2b256,   0x0131)
    define_constant(:blake2b384,   0x0132)
    define_constant(:blake2b512,   0x0133)

    define_constant(:blake2s128,   0x0134)
    define_constant(:blake2s160,   0x0135)
    define_constant(:blake2s224,   0x0136)
    define_constant(:blake2s256,   0x0137)

    define_constant(:haraka256,    0x0140)
    define_constant(:haraka512,    0x0141)

    define_constant(:shake128_256, 0x0142)
    define_constant(:shake256_512, 0x0143)

    define_constant(:sm3,          0x0144)
    define_constant(:whirlpool,    0x0145)

    define_constant(:keccak224,    0x0150)
    define_constant(:keccak256,    0x0151)
    define_constant(:keccak288,    0x0152)
    define_constant(:keccak384,    0x0153)
    define_constant(:keccak512,    0x0154)

    define_constant(:ripemd128,    0x0160)
    define_constant(:ripemd160,    0x0161)
    define_constant(:ripemd256,    0x0162)
    define_constant(:ripemd320,    0x0163)

    define_constant(:skein1024_1024, 0x0170)
    define_constant(:skein1024_384, 0x0171)
    define_constant(:skein1024_512, 0x0172)

    define_constant(:skein256_128, 0x0173)
    define_constant(:skein256_160, 0x0174)
    define_constant(:skein256_224, 0x0175)
    define_constant(:skein256_256, 0x0176)

    define_constant(:skein512_128, 0x0177)
    define_constant(:skein512_160, 0x0178)
    define_constant(:skein512_224, 0x0179)
    define_constant(:skein512_256, 0x0180)
    define_constant(:skein512_384, 0x0181)
    define_constant(:skein512_512, 0x0182)


    define_constant(:aes,          0x0201)
    define_constant(:chacha20,     0x0202)
    define_constant(:chacha20_poly1305, 0x0203)
    define_constant(:blowfish,     0x0204)
    define_constant(:camellia,     0x0205)
    define_constant(:aria,         0x0206)

    define_constant(:gcm, 0x0220)
    define_constant(:cbc, 0x0221)
    define_constant(:cfb, 0x0222)
    define_constant(:ctr, 0x0223)
    define_constant(:ccm, 0x0224)

    define_constant(:ecb, 0x0225)

    define_constant(:ofb, 0x0226)
    define_constant(:ocb, 0x0227)

    define_constant(:poly1305,   0x0228)

    define_constant(:public_key, 0x0230)
    define_constant(:x509_cert,  0x0231)
    define_constant(:cf_cert,    0x0232)


  end
end