From eaaf8aade343ff321ba382a315b41bf1cf3a54d7 Mon Sep 17 00:00:00 2001
From: "Ryan X. Charles" <ryan@bitpay.com>
Date: Mon, 1 Sep 2014 20:00:54 -0700
Subject: [PATCH] throw error if there is no string representation

---
 lib/opcode.js | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/lib/opcode.js b/lib/opcode.js
index 417213d82..04c3ccfef 100644
--- a/lib/opcode.js
+++ b/lib/opcode.js
@@ -33,7 +33,10 @@ Opcode.prototype.fromString = function(str) {
 };
 
 Opcode.prototype.toString = function() {
-  return Opcode.reverseMap[this.num];
+  var str = Opcode.reverseMap[this.num];
+  if (typeof str === 'undefined')
+    throw new Error('Opcode does not have a string representation');
+  return str;
 };
 
 Opcode.map = {