From ae9fd9fe96bad6e03b16dc068806f7408df32290 Mon Sep 17 00:00:00 2001
From: Greg Caporaso <gregcaporaso@gmail.com>
Date: Fri, 15 Jan 2016 14:38:09 -0700
Subject: [PATCH] slightly improved error message, partially addresses #1

---
 biab/util.py | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/biab/util.py b/biab/util.py
index 1ebbd0c..9be3c4b 100644
--- a/biab/util.py
+++ b/biab/util.py
@@ -63,7 +63,10 @@ def handle_starttag(self, tag, attrs):
         raise Exception("Invalid ID for section")
 
     def get_id(self):
-        return self._ID
+        try:
+            return self._ID
+        except AttributeError:
+            raise ValueError("A section is missing its ID.")
 
 class Node(object):