From a67bce4b48c56d049c26853946dce60009dd0abf Mon Sep 17 00:00:00 2001
From: "ajeffrey@roblox.com" <ajeffrey@roblox.com>
Date: Fri, 7 Jan 2022 11:36:16 -0600
Subject: [PATCH] Added example of exponential blowup

---
 rfcs/recursive-type-unrestriction.md | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/rfcs/recursive-type-unrestriction.md b/rfcs/recursive-type-unrestriction.md
index 05dab4aa..9581d7f0 100644
--- a/rfcs/recursive-type-unrestriction.md
+++ b/rfcs/recursive-type-unrestriction.md
@@ -124,7 +124,7 @@ producing unbounded type graphs during unification.
 
 ### Strict recursive type instantiations with a cache and an occurrence check
 
-We can use occurrence checks to ensure there's no blowup. We can restrict
+We can use occurrence checks to ensure there's less blowup. We can restrict
 a recursive use `T<U1,...,UN>` in the definition of `T<a1...aN>` so that either `UI` is `aI`
 or contains none of `a1...aN`. For example this bans
 ```
@@ -139,4 +139,14 @@ since `a` is not `b`, but allows:
 type T<a,b> = { foo: T<a,number>? } 
 ```
 
+This still has exponential blowup, for example
+```lua
+type T<a1,a2,a3,...,aN> = {
+  p1: T<number, a2, a3, ..., aN>,
+  p2: T<a1, number, a3, ..., aN>,
+  ...
+  pN: T<a1, a2, a3, ..., number>,
+}
+```
+
 *Advantages*: types are computed strictly, and may produce better error messages if the occurs check fails.