Macro bdk::descriptor

macro_rules! descriptor {
    ( bare ( $( $minisc:tt )* ) ) => { ... };
    ( sh ( wsh ( $( $minisc:tt )* ) ) ) => { ... };
    ( shwsh ( $( $minisc:tt )* ) ) => { ... };
    ( pk $key:expr ) => { ... };
    ( pkh $key:expr ) => { ... };
    ( wpkh $key:expr ) => { ... };
    ( sh ( wpkh ( $key:expr ) ) ) => { ... };
    ( shwpkh ( $key:expr ) ) => { ... };
    ( sh ( $( $minisc:tt )* ) ) => { ... };
    ( wsh ( $( $minisc:tt )* ) ) => { ... };
}

Macro to write full descriptors with code

This macro expands to a Result of DescriptorTemplateOut and Error

Example

Signature plus timelock, equivalent to: sh(wsh(and_v(v:pk(...), older(...))))

let my_key = bitcoin::PublicKey::from_str("02e96fe52ef0e22d2f131dd425ce1893073a3c6ad20e8cac36726393dfb4856a4c")?;
let my_timelock = 50;
let (my_descriptor, my_keys_map, networks) = bdk::descriptor!(sh ( wsh ( and_v (+v pk my_key), ( older my_timelock ))))?;

---

2-of-3 that becomes a 1-of-3 after a timelock has expired. Both descriptor_a and descriptor_b are equivalent: the first syntax is more suitable for a fixed number of items known at compile time, while the other accepts a Vec of items, which makes it more suitable for writing dynamic descriptors.

They both produce the descriptor: wsh(thresh(2,pk(...),s:pk(...),sdv:older(...)))

let my_key_1 = bitcoin::PublicKey::from_str("02e96fe52ef0e22d2f131dd425ce1893073a3c6ad20e8cac36726393dfb4856a4c")?;
let my_key_2 = bitcoin::PrivateKey::from_wif("cVt4o7BGAig1UXywgGSmARhxMdzP5qvQsxKkSsc1XEkw3tDTQFpy")?;
let my_timelock = 50;

let (descriptor_a, key_map_a, networks) = bdk::descriptor! {
    wsh (
        thresh 2, (pk my_key_1), (+s pk my_key_2), (+s+d+v older my_timelock)
    )
}?;

let b_items = vec![
    bdk::fragment!(pk my_key_1)?,
    bdk::fragment!(+s pk my_key_2)?,
    bdk::fragment!(+s+d+v older my_timelock)?,
];
let (descriptor_b, mut key_map_b, networks) = bdk::descriptor!( wsh ( thresh_vec 2, b_items ) )?;

assert_eq!(descriptor_a, descriptor_b);
assert_eq!(key_map_a.len(), key_map_b.len());

---

Simple 2-of-2 multi-signature, equivalent to: wsh(multi(2, ...))

let my_key_1 = bitcoin::PublicKey::from_str(
    "02e96fe52ef0e22d2f131dd425ce1893073a3c6ad20e8cac36726393dfb4856a4c",
)?;
let my_key_2 =
    bitcoin::PrivateKey::from_wif("cVt4o7BGAig1UXywgGSmARhxMdzP5qvQsxKkSsc1XEkw3tDTQFpy")?;

let (descriptor, key_map, networks) = bdk::descriptor! {
    wsh (
        multi 2, my_key_1, my_key_2
    )
}?;

---

Native-Segwit single-sig, equivalent to: wpkh(...)

let my_key =
    bitcoin::PrivateKey::from_wif("cVt4o7BGAig1UXywgGSmARhxMdzP5qvQsxKkSsc1XEkw3tDTQFpy")?;

let (descriptor, key_map, networks) = bdk::descriptor!(wpkh(my_key))?;