Trivial fixup.

src/bridgetree.rs

@@ -2,6 +2,7 @@
 use serde::{Deserialize, Serialize};
 
 use std::collections::HashMap;
+use std::fmt::Debug;
 use std::hash::Hash;
 
 use super::{Altitude, Hashable, Recording, Tree};
@@ -530,9 +531,7 @@ pub struct BridgeTree<H: Hash + Eq, const DEPTH: u8> {
     max_checkpoints: usize,
 }
 
-impl<H: Hashable + Hash + Eq + std::fmt::Debug, const DEPTH: u8> std::fmt::Debug
-    for BridgeTree<H, DEPTH>
-{
+impl<H: Hashable + Hash + Eq + Debug, const DEPTH: u8> Debug for BridgeTree<H, DEPTH> {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> Result<(), std::fmt::Error> {
         write!(
             f,

src/lib.rs

@@ -319,9 +319,9 @@ pub(crate) mod tests {
             "_".to_string()
         }
 
-        fn combine(_: Altitude, a: &Self, b: &Self) -> Self {
-            //format!("{}({}{})", l.0, a, b)
-            a.to_string() + b
+        fn combine(l: Altitude, a: &Self, b: &Self) -> Self {
+            format!("{}({}{})", l.0, a, b)
+            //a.to_string() + b
         }
     }