check for existence of pickled parse tables before

trying to read them.

1 files changed, 3 insertions, 0 deletions

diff --git a/ply/yacc.py b/ply/yacc.py
index eb02cc2..32e3f85 100644
--- a/ply/yacc.py
+++ b/ply/yacc.py
@@ -1982,6 +1982,9 @@ class LRTable(object):
             import cPickle as pickle
         except ImportError:
             import pickle
+        
+        if not os.path.exists(filename):
+          raise ImportError
 
         in_f = open(filename, 'rb')