From 16d700b31030af02f1354a0b76df594e0e6bfe2f Mon Sep 17 00:00:00 2001
From: David Beazley <dave@dabeaz.com>
Date: Tue, 13 Nov 2018 19:28:51 -0600
Subject: [PATCH] Some warning message refinements

---
 sly/yacc.py | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/sly/yacc.py b/sly/yacc.py
index 5e2fa9d..85046ab 100644
--- a/sly/yacc.py
+++ b/sly/yacc.py
@@ -1699,8 +1699,9 @@ class Parser(metaclass=ParserMeta):
             fail = True
 
         unused_terminals = grammar.unused_terminals()
-        for term in unused_terminals:
-            cls.log.warning('Token %r defined, but not used', term)
+        if unused_terminals:
+            unused_str = '{' + ','.join(unused_terminals) + '}'
+            cls.log.warning(f'Token{"(s)" if len(unused_terminals) >1 else ""} {unused_str} defined, but not used')
 
         unused_rules = grammar.unused_rules()
         for prod in unused_rules: