From 27ae6215e227cf30679b0eef60064799c0c6d079 Mon Sep 17 00:00:00 2001
From: Valentin Churavy <v.churavy@gmail.com>
Date: Fri, 18 Aug 2023 11:56:03 -0400
Subject: [PATCH] The careful art of type-instability

---
 base/scopedvalues.jl | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/base/scopedvalues.jl b/base/scopedvalues.jl
index fb28652937e1e..ea527f46af064 100644
--- a/base/scopedvalues.jl
+++ b/base/scopedvalues.jl
@@ -61,10 +61,11 @@ import Base: ImmutableDict
 # - Scopes are an inline implementation of an ImmutableDict, if we wanted
 #   be really fance we could use a CTrie or HAMT.
 
-mutable struct Scope{T}
+mutable struct Scope
     const parent::Union{Nothing, Scope}
-    const key::ScopedValue{T}
-    const value::T
+    const key::ScopedValue
+    const value::Any
+    Scope(parent, key::ScopedValue{T}, value::T) where T = new(parent, key, value)
 end
 Scope(parent, key::ScopedValue{T}, value) where T =
     Scope(parent, key, convert(T, value))