Declarative Syntax
The DSL specifies what needs to be done, not how.
To build a transaction, we should just say the scriptsig is a p2wpkh:bob instead of making a series of imperative calls to achieve the same goal.
Here’s how you build a transaction spending an UTXO with a p2wpkh output for Bob and creating a new UTXO as 2 of 2 multisig.
transaction inputs: [
{ tx: coinbase_tx, vout: 0, script_sig: 'p2wpkh:bob', sighash: :all }
],
outputs: [
{
policy: 'thresh(2,pk(@alice),pk(@bob))',
amount: 49.999.sats
}
]Similarly, to add a OP_CSV constraint on a transaction output we specify the csv: NN as a keyword option to the output.
Here’s an example from the ARK transactions using the csv keyword.
transaction inputs: [
{ tx: @funding_tx,
vout: 0,
script_sig: 'p2wpkh:asp_timelock nulldummy nulldummy nulldummy',
csv: 10 }
],
outputs: [
{
descriptor: 'wpkh(@asp)',
amount: 49.998.sats
}
]