examples: Refactor htlc

In an effort to make the example more clear; refactor the
`htlc` example.

Refactor only, no logic changes.

Author: tcharding

examples/htlc.rs

@@ -24,7 +24,7 @@ use miniscript::DescriptorTrait;
 use std::str::FromStr;
 
 fn main() {
-    //HTLC policy with 10:1 odds for happy(co-operative) case compared to uncooperative case
+    // HTLC policy with 10:1 odds for happy (co-operative) case compared to uncooperative case.
     let htlc_policy = Concrete::<bitcoin::PublicKey>::from_str(&format!("or(10@and(sha256({secret_hash}),pk({redeem_identity})),1@and(older({expiry}),pk({refund_identity})))",
                                                   secret_hash = "1111111111111111111111111111111111111111111111111111111111111111",
                                                   redeem_identity = "022222222222222222222222222222222222222222222222222222222222222222",
@@ -39,31 +39,34 @@ fn main() {
     )
     .expect("Resource limits");
 
-    // Check whether the descriptor is safe
-    // This checks whether all spend paths are accessible in bitcoin network.
-    // It maybe possible that some of the spend require more than 100 elements in Wsh scripts
-    // Or they contain a combination of timelock and heightlock.
+    // Check whether the descriptor is safe. This checks whether all spend paths are accessible in
+    // the Bitcoin network. It may be possible that some of the spend paths require more than 100
+    // elements in Wsh scripts or they contain a combination of timelock and heightlock.
     assert!(htlc_descriptor.sanity_check().is_ok());
     assert_eq!(
         format!("{}", htlc_descriptor),
         "wsh(andor(pk(022222222222222222222222222222222222222222222222222222222222222222),sha256(1111111111111111111111111111111111111111111111111111111111111111),and_v(v:pkh(51814f108670aced2d77c1805ddd6634bc9d4731),older(4444))))#s0qq76ng"
     );
 
+    // Lift the descriptor into an abstract policy.
     assert_eq!(
         format!("{}", htlc_descriptor.lift().unwrap()),
         "or(and(pkh(4377a5acd66dc5cb67148a24818d1e51fa183bd2),sha256(1111111111111111111111111111111111111111111111111111111111111111)),and(pkh(51814f108670aced2d77c1805ddd6634bc9d4731),older(4444)))"
     );
 
+    // Get the scriptPpubkey for this Wsh descriptor.
     assert_eq!(
         format!("{:x}", htlc_descriptor.spk()),
         "0020d853877af928a8d2a569c9c0ed14bd16f6a80ce9cccaf8a6150fd8f7f8867ae2"
     );
 
+    // Encode the Wsh descriptor into a Bitcoin script.
     assert_eq!(
         format!("{:x}", htlc_descriptor.inner_script()),
         "21022222222222222222222222222222222222222222222222222222222222222222ac6476a91451814f108670aced2d77c1805ddd6634bc9d473188ad025c11b26782012088a82011111111111111111111111111111111111111111111111111111111111111118768"
     );
 
+    // Get the address for this Wsh descriptor.v
     assert_eq!(
         format!("{}", htlc_descriptor.address(Network::Bitcoin).unwrap()),
         "bc1qmpfcw7he9z5d9ftfe8qw699azmm2sr8fen903fs4plv007yx0t3qxfmqv5"