cashscript_py.helpers.cashtoken module

Utility functions for CashTokens operations (token-aware outputs and address detection).

is_token_address(address: str) → bool[source]

Detect whether a CashAddr is token-aware by inspecting its version byte.

Parameters:

address – CashAddr string with prefix.

Returns:

True if the address indicates a token-aware version; False otherwise.

serialize_token_prefix(token: TokenDetails | None) → bytes[source]

Serialize a CashTokens token prefix.

Layout (when present):

  • 0xef (PREFIX_TOKEN)

  • token category (32 bytes), encoded in OP_HASH256 byte order (reversed txid)

  • token bitfield (1 byte):
    high nibble (structure):

    0x40 -> HAS_COMMITMENT_LENGTH (commitment length + commitment follow) 0x20 -> HAS_NFT (low nibble encodes capability: 0x00 none, 0x01 mutable, 0x02 minting) 0x10 -> HAS_AMOUNT (fungible amount follows as varint) 0x80 -> RESERVED (must be 0)

    low nibble (nft_capability):

    0x00 none (immutable), 0x01 mutable, 0x02 minting

  • [NFT commitment length (varint) + commitment (bytes)] if 0x40

  • [fungible amount (varint)] if 0x10

Returns:

the token prefix bytes, or empty bytes if token is None.

Return type:

bytes