diff --git a/src/extensions/transformed.rs b/src/extensions/transformed.rs
index 20d865a..6eadd41 100644
--- a/src/extensions/transformed.rs
+++ b/src/extensions/transformed.rs
@@ -34,7 +34,7 @@ impl fmt::Display for TransformedExtensions {
 }
 
 pub fn parse_transformed_extensions<'a>(
-    mut iter: &mut Peekable<impl Iterator<Item = &'a str>>,
+    iter: &mut Peekable<impl Iterator<Item = &'a str>>,
 ) -> Result<TransformedExtensions, ParserError> {
     // transformed_extensions
     // https://unicode.org/reports/tr35/#transformed_extensions
@@ -73,7 +73,7 @@ pub fn parse_transformed_extensions<'a>(
             tvalue.push(subtag.to_string());
             iter.next();
         } else if is_language_subtag(subtag_bytes) {
-            tlang = Some(parse_unicode_language_id_from_iter(&mut iter)?);
+            tlang = Some(parse_unicode_language_id_from_iter(iter)?);
         } else {
             return Err(ParserError::InvalidSubtag);
         }
diff --git a/src/lib.rs b/src/lib.rs
index 6fd6ebe..4a7c933 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -6,18 +6,18 @@
 //!
 //! ## 🚀 Usages
 //!
-//! ```rust
+//! ```
 //! use unicode_locale_parser::parse_locale_id;
 //!
-//! fn main() {
-//!     // simple language
-//!     let locale = parse_locale_id("ja-JP");
-//!     println!("{:#?}", locale);
+//! # fn main() {
+//! // simple language
+//! let locale = parse_locale_id("ja-JP");
+//! println!("{:#?}", locale);
 //!
-//!     // language & unicode locale extension
-//!     let locale = parse_locale_id("de-Latn-DE-u-ca-buddhist");
-//!     println!("{:#?}", locale);
-//! }
+//! // language & unicode locale extension
+//! let locale = parse_locale_id("de-Latn-DE-u-ca-buddhist");
+//! println!("{:#?}", locale);
+//! # }
 //! ```
 //!
 //! ## 🤝 API
diff --git a/src/measure.rs b/src/measure.rs
index b281d9c..7fa2aa0 100644
--- a/src/measure.rs
+++ b/src/measure.rs
@@ -15,7 +15,7 @@ impl fmt::Display for UnicodeMeasureUnit {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         let mut messages = vec![];
         for value in &self.values {
-            messages.push(format!("{}", value));
+            messages.push(value.to_string());
         }
         write!(f, "{}", messages.join(&SEP.to_string()))?;
         Ok(())