diff --git a/tests/playground/ir.lean b/tests/playground/ir.lean
index 67d755dcca..2674a7ba81 100644
--- a/tests/playground/ir.lean
+++ b/tests/playground/ir.lean
@@ -5,7 +5,7 @@ def tst1 : IO Unit :=
 let fbody : FnBody :=
    FnBody.vdecl `x IRType.uint32 (Expr.lit (LitVal.num 0)) $
    FnBody.ret `x in
-IO.println $ toFormat fbody
+IO.println $ format fbody
 
 def main : IO Unit :=
 tst1