diff --git a/phf/src/map.rs b/phf/src/map.rs
index f0bd039d..c5ba2e5b 100644
--- a/phf/src/map.rs
+++ b/phf/src/map.rs
@@ -26,11 +26,7 @@ pub struct Map<K:'static, V:'static> {
 
 impl<K, V> fmt::Debug for Map<K, V> where K: fmt::Debug, V: fmt::Debug {
     fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
-        let mut builder = fmt.debug_map();
-        for (k, v) in self {
-            builder = builder.entry(k, v);
-        }
-        builder.finish()
+        self.entries().fold(fmt.debug_map(), |b, (k, v)| b.entry(k, v)).finish()
     }
 }
 
diff --git a/phf/src/ordered_map.rs b/phf/src/ordered_map.rs
index 2b3705a7..f85322c4 100644
--- a/phf/src/ordered_map.rs
+++ b/phf/src/ordered_map.rs
@@ -32,11 +32,7 @@ pub struct OrderedMap<K:'static, V:'static> {
 
 impl<K, V> fmt::Debug for OrderedMap<K, V> where K: fmt::Debug, V: fmt::Debug {
     fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
-        let mut builder = fmt.debug_map();
-        for (k, v) in self {
-            builder = builder.entry(k, v);
-        }
-        builder.finish()
+        self.entries().fold(fmt.debug_map(), |b, (k, v)| b.entry(k, v)).finish()
     }
 }
 
diff --git a/phf/src/ordered_set.rs b/phf/src/ordered_set.rs
index f41239f3..0baf8959 100644
--- a/phf/src/ordered_set.rs
+++ b/phf/src/ordered_set.rs
@@ -23,11 +23,7 @@ pub struct OrderedSet<T:'static> {
 
 impl<T> fmt::Debug for OrderedSet<T> where T: fmt::Debug {
     fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
-        let mut builder = fmt.debug_set();
-        for entry in self {
-            builder = builder.entry(entry);
-        }
-        builder.finish()
+        self.iter().fold(fmt.debug_set(), |b, e| b.entry(e)).finish()
     }
 }
 
diff --git a/phf/src/set.rs b/phf/src/set.rs
index ec564743..66bc1ed5 100644
--- a/phf/src/set.rs
+++ b/phf/src/set.rs
@@ -22,11 +22,7 @@ pub struct Set<T:'static> {
 
 impl<T> fmt::Debug for Set<T> where T: fmt::Debug {
     fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
-        let mut builder = fmt.debug_set();
-        for entry in self {
-            builder = builder.entry(entry);
-        }
-        builder.finish()
+        self.iter().fold(fmt.debug_set(), |b, e| b.entry(e)).finish()
     }
 }