From b329aecf836bfcffeae30dbf493a8a838bf14bab Mon Sep 17 00:00:00 2001
From: Tyler Veness <calcmogul@gmail.com>
Date: Sun, 17 Dec 2023 21:55:27 -0800
Subject: [PATCH] Add comment for dependent variable warning (#242)

---
 src/autodiff/Variable.cpp | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/autodiff/Variable.cpp b/src/autodiff/Variable.cpp
index 30008382..f88f591b 100644
--- a/src/autodiff/Variable.cpp
+++ b/src/autodiff/Variable.cpp
@@ -34,6 +34,8 @@ Variable& Variable::SetValue(double value) {
   if (detail::IsZero(expr)) {
     expr = detail::MakeExpressionPtr(value);
   } else {
+    // We only need to check the first argument since unary and binary operators
+    // both use it
     if (!detail::IsZero(expr->args[0])) {
       fmt::print(stderr,
                  "WARNING: {}:{}: Modified the value of a dependent variable\n",
@@ -48,6 +50,8 @@ Variable& Variable::SetValue(int value) {
   if (detail::IsZero(expr)) {
     expr = detail::MakeExpressionPtr(value);
   } else {
+    // We only need to check the first argument since unary and binary operators
+    // both use it
     if (!detail::IsZero(expr->args[0])) {
       fmt::print(stderr,
                  "WARNING: {}:{}: Modified the value of a dependent variable\n",