From ab6b1905e51965a26ac944aefd7712668d4afadb Mon Sep 17 00:00:00 2001
From: Juha Jeronen <juha.jeronen@jyu.fi>
Date: Wed, 15 May 2019 15:31:35 +0300
Subject: [PATCH] Avoid crashing in error logger when the message of a macro
 expansion error is not a string.

---
 macropy/core/failure.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/macropy/core/failure.py b/macropy/core/failure.py
index 6eeff151..28779aad 100644
--- a/macropy/core/failure.py
+++ b/macropy/core/failure.py
@@ -24,7 +24,7 @@ def clear_errors(tree, **kw):
         tb = "".join(traceback.format_tb(tree.__traceback__))
         msg = str(tree)
         if type(tree) is not AssertionError or tree.args == ():
-            msg = ("".join(tree.args) + "\nCaused by Macro-Expansion Error:\n" +
+            msg = ("".join(str(x) for x in tree.args) + "\nCaused by Macro-Expansion Error:\n" +
                    tb)
         return hq[raise_error(MacroExpansionError(msg))]
     else: