The following functions and operators are available when compiling Ivy to Bitcoin Script:
checkSig(publicKey: PublicKey, sig: Signature) -> Boolean: check that the signature sig is a valid signature on the spending transaction by the private key corresponding to publicKey.
checkMultiSig(publicKeys: [PublicKey], sigs: [Signature]) -> Boolean: check that each of the signatures in sigs is a valid signature on the spending transaction by the private key corresponding to one of the publicKeys. The signatures must be provided in the same order as their respective public keys.
after(time: Time) -> Boolean: check that the current block time (or block height) is after time. This uses the transaction’s nLockTime field and the CHECKLOCKTIMEVERIFY instruction.
older(duration: Duration) -> Boolean: check that the contract being spent has been on the blockchain for at least duration (w). This uses the input’s sequence number and the CHECKSEQUENCEVERIFY instruction.
sha256(preimage: (T: HashableType)) -> Sha256(T): compute the SHA-256 hash of preimage
sha1(preimage: (T: HashableType)) -> Sha1(T): compute the SHA-1 hash of preimage
ripemd160(preimage: (T: HashableType)) -> Ripemd160(T): compute the RIPEMD-160 hash of preimage
bytes(item: T) -> Bytes: coerce
itemto a bytestring (of type Bytes). This function does not have any effect on the compiled output or on script execution (since the Bitcoin Script VM treats every item as a bytestring); it only affects typechecking. (This cannot be called on an item of type Value or Boolean.)
size(bytestring: Bytes) -> Number: get the length of
==, !=: check equality of any two values of the same type. (Note: because of certain limitations of Bitcoin Script, using these operators on Booleans is not allowed.)