diff --git a/src/builtins/time/compat.rs b/src/builtins/time/compat.rs
index f2af5a8..04feba7 100644
--- a/src/builtins/time/compat.rs
+++ b/src/builtins/time/compat.rs
@@ -267,7 +267,7 @@ struct GoTimeFormatItems<'a> {
 }
 
 impl GoTimeFormatItems<'_> {
-    fn parse(reminder: &str) -> GoTimeFormatItems {
+    fn parse(reminder: &str) -> GoTimeFormatItems<'_> {
         GoTimeFormatItems {
             reminder,
             queue: &[],
@@ -275,7 +275,7 @@ impl GoTimeFormatItems<'_> {
         }
     }
 
-    fn format(reminder: &str) -> GoTimeFormatItems {
+    fn format(reminder: &str) -> GoTimeFormatItems<'_> {
         GoTimeFormatItems {
             reminder,
             queue: &[],
diff --git a/src/builtins/units.rs b/src/builtins/units.rs
index 46af0ce..55bbb18 100644
--- a/src/builtins/units.rs
+++ b/src/builtins/units.rs
@@ -108,7 +108,7 @@ fn parse(span: &Span, params: &[Ref<Expr>], args: &[Value], _strict: bool) -> Re
         n.mul_assign(&Number::two_pow(e)?)?;
         Ok(Value::from(n))
     } else {
-        return Ok(Value::Undefined);
+        Ok(Value::Undefined)
     }
 }
 
diff --git a/src/engine.rs b/src/engine.rs
index d7ec5f3..b33aff4 100644
--- a/src/engine.rs
+++ b/src/engine.rs
@@ -23,12 +23,14 @@ pub struct Engine {
     rego_v1: bool,
 }
 
+#[cfg(feature = "azure_policy")]
 #[derive(Debug, Clone, Serialize)]
 pub struct PolicyPackageNameDefinition {
     pub source_file: String,
     pub package_name: String,
 }
 
+#[cfg(feature = "azure_policy")]
 #[derive(Debug, Clone, Serialize)]
 pub struct PolicyParameter {
     pub name: String,
@@ -36,11 +38,13 @@ pub struct PolicyParameter {
     pub required: bool,
 }
 
+#[cfg(feature = "azure_policy")]
 #[derive(Debug, Clone, Serialize)]
 pub struct PolicyModifier {
     pub name: String,
 }
 
+#[cfg(feature = "azure_policy")]
 #[derive(Debug, Clone, Serialize)]
 pub struct PolicyParameters {
     pub source_file: String,
@@ -954,7 +958,7 @@ impl Engine {
     #[cfg_attr(docsrs, doc(cfg(feature = "azure_policy")))]
     pub fn get_policy_package_names(&self) -> Result<Vec<PolicyPackageNameDefinition>> {
         let mut package_names = vec![];
-        for m in &self.modules {
+        for m in self.modules.iter() {
             let package_name = Interpreter::get_path_string(&m.package.refr, None)?;
             package_names.push(PolicyPackageNameDefinition {
                 source_file: m.package.span.source.file().to_string(),
@@ -987,7 +991,7 @@ impl Engine {
     #[cfg_attr(docsrs, doc(cfg(feature = "azure_policy")))]
     pub fn get_policy_parameters(&self) -> Result<Vec<PolicyParameters>> {
         let mut policy_parameter_definitions = vec![];
-        for m in &self.modules {
+        for m in self.modules.iter() {
             let mut parameters = vec![];
             let mut modifiers = vec![];
 
diff --git a/src/interpreter.rs b/src/interpreter.rs
index cf1abb0..d9a1ed9 100644
--- a/src/interpreter.rs
+++ b/src/interpreter.rs
@@ -3696,9 +3696,7 @@ impl Interpreter {
                 MapEntry::Occupied(o) => {
                     if idx + 1 == comps.len() {
                         for (_, i) in o.get() {
-                            if index.is_some() && i.is_some() {
-                                let old = i.as_ref().unwrap();
-                                let new = index.as_ref().unwrap();
+                            if let (Some(old), Some(new)) = (i, &index) {
                                 if old == new {
                                     bail!(refr.span().error("multiple default rules for the variable with the same index"));
                                 }
diff --git a/src/lexer.rs b/src/lexer.rs
index 5888300..e792cb5 100644
--- a/src/lexer.rs
+++ b/src/lexer.rs
@@ -120,7 +120,7 @@ impl cmp::Eq for SourceStr {}
 
 impl cmp::PartialOrd for SourceStr {
     fn partial_cmp(&self, other: &Self) -> Option<cmp::Ordering> {
-        Some(self.text().cmp(other.text()))
+        Some(self.cmp(other))
     }
 }