diff --git a/immut/array/array.mbt b/immut/array/array.mbt
index 9375262a6..e9f8980cc 100644
--- a/immut/array/array.mbt
+++ b/immut/array/array.mbt
@@ -379,6 +379,7 @@ pub impl[X : @quickcheck.Arbitrary] @quickcheck.Arbitrary for T[X] with arbitrar
   @quickcheck.Arbitrary::arbitrary(size, rs) |> from_array
 }
 
+///|
 pub impl[A : Hash] Hash for T[A] with hash_combine(self, hasher) {
   for e in self {
     hasher.combine(e)
diff --git a/immut/priority_queue/priority_queue.mbt b/immut/priority_queue/priority_queue.mbt
index 77ba320eb..31d44c806 100644
--- a/immut/priority_queue/priority_queue.mbt
+++ b/immut/priority_queue/priority_queue.mbt
@@ -234,10 +234,12 @@ pub fn to_string[A : Show + Compare](self : T[A]) -> String {
   Show::to_string(self)
 }
 
+///|
 pub impl[A : Compare] Eq for T[A] with op_equal(self, other) {
   self.length() == other.length() && self.to_array() == other.to_array()
 }
 
+///|
 pub impl[A : Hash + Compare] Hash for T[A] with hash_combine(self, hasher) {
   for e in self {
     hasher.combine(e)
diff --git a/immut/sorted_map/map.mbt b/immut/sorted_map/map.mbt
index 32e3ebc0f..83a4613e8 100644
--- a/immut/sorted_map/map.mbt
+++ b/immut/sorted_map/map.mbt
@@ -140,6 +140,7 @@ pub impl[K : @quickcheck.Arbitrary + Compare, V : @quickcheck.Arbitrary] @quickc
   @quickcheck.Arbitrary::arbitrary(size, rs) |> from_array
 }
 
+///|
 pub impl[K : Hash, V : Hash] Hash for T[K, V] with hash_combine(self, hasher) {
   for e in self {
     hasher..combine(e.0).combine(e.1)