Merge branch 'master' into 0.7d

lark/__init__.py

@@ -5,4 +5,4 @@ from .exceptions import ParseError, LexError, GrammarError, UnexpectedToken, Une
 from .lexer import Token
 from .lark import Lark
 
-__version__ = "0.6.5"
+__version__ = "0.6.6"

lark/load_grammar.py

@@ -511,7 +511,7 @@ class Grammar:
 
                 empty_indices = [x==_EMPTY for i, x in enumerate(expansion)]
                 if any(empty_indices):
-                    exp_options = copy(options) or RuleOptions()
+                    exp_options = copy(options) if options else RuleOptions()
                     exp_options.empty_indices = empty_indices
                     expansion = [x for x in expansion if x!=_EMPTY]
                 else: