From 850de8a2bf34fb12969d356488a12cabdff76164 Mon Sep 17 00:00:00 2001
From: Sasha Koshka <supergriffin64@gmail.com>
Date: Sun, 28 Aug 2022 18:22:11 -0400
Subject: [PATCH] Fix out of bounds errors in Machine.Pop

---
 creature.go | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/creature.go b/creature.go
index 5fd8b75..f080a83 100644
--- a/creature.go
+++ b/creature.go
@@ -224,6 +224,10 @@ func (machine *Machine) Push(word int) {
 // Pop pops the last word off of the stack, and returns it, decreasing the stack
 // pointer and reallocating the stack if necessary.
 func (machine *Machine) Pop() (word int) {
+	if machine.pointer <= 0 || machine.pointer >= len(machine.stack) {
+		return
+	}
+	
 	word = machine.stack[machine.pointer]
 	machine.pointer--