1 files changed, 10 insertions, 0 deletions
diff --git a/tvix/eval/src/value/thunk.rs b/tvix/eval/src/value/thunk.rs
index 3c3941e49402..307eb23a75f6 100644
--- a/tvix/eval/src/value/thunk.rs
+++ b/tvix/eval/src/value/thunk.rs
@@ -20,6 +20,7 @@
 
 use std::{
     cell::{Ref, RefCell, RefMut},
+    fmt::Display,
     rc::Rc,
 };
 
@@ -131,3 +132,12 @@ impl UpvalueCarrier for Thunk {
         })
     }
 }
+
+impl Display for Thunk {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match &*self.0.borrow() {
+            ThunkRepr::Evaluated(v) => v.fmt(f),
+            _ => f.write_str("internal[thunk]"),
+        }
+    }
+}