seems to be there could be a script op OP_TRANSACTIONEXISTS that would enable on-blockchain exchanges from one crypto to another. it would take on the stack an address, an amount, a name or symbol of a cryptocurrency, and possibly a number of confirmations. if everything matches, the address that sent the transaction would be pushed onto the stack, and the "pay to" script could then send the funds in exchange. it would require a multicurrency daemon that maintains several different blockchains at the same time, and the clients would have to generate their addresses for the different currencies from the same RIPEMD160 hash.
last updated 2018-02-05 11:08:56. served from tektonic.jcomeau.com