as_ref_mut solution

exercises/23_conversions/as_ref_mut.rs

@@ -3,22 +3,21 @@
 // https://doc.rust-lang.org/std/convert/trait.AsMut.html, respectively.
 
 // Obtain the number of bytes (not characters) in the given argument.
-// TODO: Add the AsRef trait appropriately as a trait bound.
+// TODO: Add the `AsRef` trait appropriately as a trait bound.
 fn byte_counter<T>(arg: T) -> usize {
     arg.as_ref().as_bytes().len()
 }
 
 // Obtain the number of characters (not bytes) in the given argument.
-// TODO: Add the AsRef trait appropriately as a trait bound.
+// TODO: Add the `AsRef` trait appropriately as a trait bound.
 fn char_counter<T>(arg: T) -> usize {
     arg.as_ref().chars().count()
 }
 
-// Squares a number using as_mut().
+// Squares a number using `as_mut()`.
 // TODO: Add the appropriate trait bound.
 fn num_sq<T>(arg: &mut T) {
     // TODO: Implement the function body.
-    ???
 }
 
 fn main() {