comment fixes for ToPkCtx removal

Author: apoelstra

src/descriptor/mod.rs

@@ -278,11 +278,6 @@ impl<
 {
 }
 
-// There are some additional convenience functions we could add to  `TranslatePk`
-// for the common special cases where `P::Hash == Q::Hash`, or when `P == P::Hash`,
-// but these are blocked on https://github.com/rust-lang/rust/issues/20041 which
-// is unlikely to arrive in Rust very soon, as of Jan 2021. Should revisit this.
-
 /// Script descriptor
 #[derive(Clone, PartialEq, Eq, PartialOrd, Ord)]
 pub enum Descriptor<Pk: MiniscriptKey> {
@@ -559,6 +554,8 @@ where
 
 impl Descriptor<DescriptorPublicKey> {
     /// Derives all wildcard keys in the descriptor using the supplied index
+    ///
+    /// Panics if given an index ≥ 2^31
     pub fn derive(&self, index: u32) -> Descriptor<DescriptorPublicKey> {
         self.translate_pk2_infallible(|pk| pk.clone().derive(index))
     }

src/lib.rs

@@ -69,11 +69,6 @@
 //!         )))\
 //!     ").unwrap();
 //!
-//!     // Sometimes it is necessary to have additional information to get the bitcoin::PublicKey
-//!     // from the MiniscriptKey which can supplied by `to_pk_ctx` parameter. For example,
-//!     // when calculating the script pubkey of a descriptor with xpubs, the secp context and
-//!     // child information maybe required.
-//!
 //!     // Derive the P2SH address
 //!     assert_eq!(
 //!         desc.address(bitcoin::Network::Bitcoin).unwrap().to_string(),
@@ -189,11 +184,6 @@ impl MiniscriptKey for String {
 /// Trait describing public key types which can be converted to bitcoin pubkeys
 pub trait ToPublicKey: MiniscriptKey {
     /// Converts an object to a public key
-    /// C represents additional context information that maybe
-    /// required for deriving a bitcoin::PublicKey from MiniscriptKey
-    /// You may require secp context for crypto operations
-    /// or additional information for substituting the wildcard in
-    /// extended pubkeys
     fn to_public_key(&self) -> bitcoin::PublicKey;
 
     /// Converts a hashed version of the public key to a `hash160` hash.