diff --git a/compiler/evaluate/eval.cpp b/compiler/evaluate/eval.cpp
index d38a0d650b..d6d31de3d2 100644
--- a/compiler/evaluate/eval.cpp
+++ b/compiler/evaluate/eval.cpp
@@ -584,6 +584,9 @@ static Tree realeval(Tree exp, Tree visited, Tree localValEnv)
             throw faustexception(error.str());
         }
 
+    } else if (isBoxOndemand(exp, body)) {
+        return boxOndemand(eval(body, visited, localValEnv));
+
     } else if (isBoxSlot(exp)) {
         return exp;