Block hash can suggest much higher difficulty than what is in effect, so OP_CHECKBLOCKATHEIGHT would not work to decide if difficulty is above the level of the bet. > On May 23, 2019, at 21:45, Tamas Blummer wrote: > > I see. The uncompressing needs to be done either to compare. How are chances for that BIP? > > This BIP would be explicitly offering risk managment of miners biggest risk. > Doing so without relying on external markets or oracle, self cointained would be an impressive and adequate feature. > > Tamas Blummer > >> On May 23, 2019, at 21:21, Nathan Cook wrote: >> >> It's true that it fetches the block hash; the idea is to compare the block hash's numeric value to the desired (uncompressed) difficulty directly, using a 256-bit version of OP_LESSTHAN. >> >> Nathan Cook >> >> >> On Thu, 23 May 2019 at 22:18, Tamas Blummer wrote: >> That opcode would not help as it fetches block hash and not the content of the header. >> >>> On May 23, 2019, at 21:05, Nathan Cook wrote: >>> >>> You can get the same effect with OP_CHECKBLOCKATHEIGHT as proposed by Luke Dashjr (https://github.com/luke-jr/bips/blob/bip-cbah/bip-cbah.mediawiki) if you also re-enable/extend certain opcodes like OP_AND and OP_LESSTHAN. See https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2016-September/013149.html and the ensuing thread. >>> >>> Nathan Cook >>> >>> >>> On Thu, 23 May 2019 at 21:33, Tamas Blummer via bitcoin-dev wrote: >>> Difficulty change has profound impact on miner’s production thereby introduce the biggest risk while considering an investment. >>> Commodity markets offer futures and options to hedge risks on traditional trading venues. Some might soon list difficulty futures. >>> >>> I think we could do much better than them natively within Bitcoin. >>> >>> A better solution could be a transaction that uses nLocktime denominated in block height, such that it is valid after the difficulty adjusted block in the future. >>> A new OP_DIFFICULTY opcode would put onto stack the value of difficulty for the block the transaction is included into. >>> The output script may then decide comparing that value with a strike which key can spend it. >>> The input of the transaction would be a multi-sig escrow of those who entered the bet. >>> The winner would broadcast. >>> >>> Once signed by both the transaction would not carry any counterparty risk and would not need an oracle to settle according to the bet. >>> >>> I plan to draft a BIP for this as I think this opcode would serve significant economic interest of Bitcoin economy, and is compatible with Bitcoin’s aim not to introduce 3rd party to do so. >>> >>> Do you see a fault in this proposal or want to contribute? >>> >>> Tamas Blummer >>> >>> _______________________________________________ >>> bitcoin-dev mailing list >>> bitcoin-dev@lists.linuxfoundation.org >>> https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev >> >