Remove explicit lifetimes

Clippy emits:

 warning: explicit lifetimes given in parameter types where they could
 be elided (or replaced with `'_` if needed by type declaration)

As suggested, remove explicit lifetimes and use `'_`,

Author: tcharding

src/interpreter/inner.rs

@@ -37,8 +37,8 @@ fn pk_from_slice(slice: &[u8], require_compressed: bool) -> Result<bitcoin::Publ
     }
 }
 
-fn pk_from_stackelem<'a>(
-    elem: &stack::Element<'a>,
+fn pk_from_stackelem(
+    elem: &stack::Element<'_>,
     require_compressed: bool,
 ) -> Result<bitcoin::PublicKey, Error> {
     let slice = if let stack::Element::Push(slice) = *elem {
@@ -51,8 +51,8 @@ fn pk_from_stackelem<'a>(
 
 // Parse the script with appropriate context to check for context errors like
 // correct usage of x-only keys or multi_a
-fn script_from_stackelem<'a, Ctx: ScriptContext>(
-    elem: &stack::Element<'a>,
+fn script_from_stackelem<Ctx: ScriptContext>(
+    elem: &stack::Element<'_>,
 ) -> Result<Miniscript<Ctx::Key, Ctx>, Error> {
     match *elem {
         stack::Element::Push(sl) => {

src/miniscript/lex.rs

@@ -113,7 +113,7 @@ impl<'s> Iterator for TokenIter<'s> {
 }
 
 /// Tokenize a script
-pub fn lex<'s>(script: &'s script::Script) -> Result<Vec<Token<'s>>, Error> {
+pub fn lex(script: &'_ script::Script) -> Result<Vec<Token<'_>>, Error> {
     let mut ret = Vec::with_capacity(script.len());
 
     for ins in script.instructions_minimal() {

src/psbt/finalizer.rs

@@ -117,7 +117,7 @@ pub(super) fn get_utxo(psbt: &Psbt, index: usize) -> Result<&bitcoin::TxOut, Inp
 }
 
 /// Get the Prevouts for the psbt
-pub(super) fn prevouts<'a>(psbt: &'a Psbt) -> Result<Vec<&bitcoin::TxOut>, super::Error> {
+pub(super) fn prevouts(psbt: &Psbt) -> Result<Vec<&bitcoin::TxOut>, super::Error> {
     let mut utxos = vec![];
     for i in 0..psbt.inputs.len() {
         let utxo_ref = get_utxo(psbt, i).map_err(|e| Error::InputError(e, i))?;