Move write! arguments directly into the string

src/librustdoc/html/render/mod.rs

@@ -1039,8 +1039,8 @@ fn render_attributes_in_pre<'a, 'b: 'a>(
 // When an attribute is rendered inside a <code> tag, it is formatted using
 // a div to produce a newline after it.
 fn render_attributes_in_code(w: &mut impl fmt::Write, it: &clean::Item, tcx: TyCtxt<'_>) {
-    for a in it.attributes(tcx, false) {
-        write!(w, "<div class=\"code-attribute\">{}</div>", a).unwrap();
+    for attr in it.attributes(tcx, false) {
+        write!(w, "<div class=\"code-attribute\">{attr}</div>").unwrap();
     }
 }
 

src/librustdoc/html/render/print_item.rs

@@ -1435,17 +1435,17 @@ fn item_proc_macro(
         let name = it.name.expect("proc-macros always have names");
         match m.kind {
             MacroKind::Bang => {
-                write!(buffer, "{}!() {{ /* proc-macro */ }}", name).unwrap();
+                write!(buffer, "{name}!() {{ /* proc-macro */ }}").unwrap();
             }
             MacroKind::Attr => {
-                write!(buffer, "#[{}]", name).unwrap();
+                write!(buffer, "#[{name}]").unwrap();
             }
             MacroKind::Derive => {
-                write!(buffer, "#[derive({})]", name).unwrap();
+                write!(buffer, "#[derive({name})]").unwrap();
                 if !m.helpers.is_empty() {
                     buffer.write_str("\n{\n    // Attributes available to this derive:\n").unwrap();
                     for attr in &m.helpers {
-                        writeln!(buffer, "    #[{}]", attr).unwrap();
+                        writeln!(buffer, "    #[{attr}]").unwrap();
                     }
                     buffer.write_str("}\n").unwrap();
                 }