Style improvement

Author: Noratrieb

compiler/rustc_parse/src/parser/item.rs

@@ -1143,8 +1143,9 @@ impl<'a> Parser<'a> {
                     Ok(kind) => kind,
                     Err(kind) => match kind {
                         ItemKind::Const(box ConstItem { ty, expr, .. }) => {
-                            let const_span = Some(span.with_hi(ident.span.lo()))
-                                .filter(|span| span.can_be_used_for_suggestions());
+                            let const_span = span
+                                .can_be_used_for_suggestions()
+                                .then(|| span.with_hi(ident.span.lo()));
                             self.sess.emit_err(errors::ExternItemCannotBeConst {
                                 ident_span: ident.span,
                                 const_span,