From 64145a8fef27503797c12a31c670f30aeeae7cbc Mon Sep 17 00:00:00 2001
From: David Widmann <devmotion@users.noreply.github.com>
Date: Mon, 5 Jun 2023 21:47:16 +0200
Subject: [PATCH] Revert "Update abs diff rule to 0 at non-differentiable
 point" (#100)

---
 src/rules.jl | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/rules.jl b/src/rules.jl
index 7b9b59e..caa3078 100644
--- a/src/rules.jl
+++ b/src/rules.jl
@@ -70,7 +70,7 @@
 
 # We provide this hook for special number types like `Interval`
 # that need their own special definition of `abs`.
-_abs_deriv(x) = sign(x)
+_abs_deriv(x) = signbit(x) ? -one(x) : one(x)
 
 # binary #
 #--------#