More minor refactorings

lark/exceptions.py

@@ -129,6 +129,8 @@ class UnexpectedInput(LarkError):
 
 class UnexpectedEOF(ParseError, UnexpectedInput):
     def __init__(self, expected, state=None, terminals_by_name=None):
+        super(UnexpectedEOF, self).__init__()
+
         self.expected = expected
         self.state = state
         from .lexer import Token
@@ -138,7 +140,6 @@ class UnexpectedEOF(ParseError, UnexpectedInput):
         self.column = -1
         self._terminals_by_name = terminals_by_name
 
-        super(UnexpectedEOF, self).__init__()
 
     def __str__(self):
         message = "Unexpected end-of-input. "
@@ -149,6 +150,8 @@ class UnexpectedEOF(ParseError, UnexpectedInput):
 class UnexpectedCharacters(LexError, UnexpectedInput):
     def __init__(self, seq, lex_pos, line, column, allowed=None, considered_tokens=None, state=None, token_history=None,
                  terminals_by_name=None, considered_rules=None):
+        super(UnexpectedCharacters, self).__init__()
+
         # TODO considered_tokens and allowed can be figured out using state
         self.line = line
         self.column = column
@@ -167,7 +170,6 @@ class UnexpectedCharacters(LexError, UnexpectedInput):
             self.char = seq[lex_pos]
         self._context = self.get_context(seq)
 
-        super(UnexpectedCharacters, self).__init__()
 
     def __str__(self):
         message = "No terminal matches '%s' in the current parser context, at line %d col %d" % (self.char, self.line, self.column)
@@ -190,6 +192,8 @@ class UnexpectedToken(ParseError, UnexpectedInput):
     """
 
     def __init__(self, token, expected, considered_rules=None, state=None, interactive_parser=None, terminals_by_name=None, token_history=None):
+        super(UnexpectedToken, self).__init__()
+        
         # TODO considered_rules and expected can be figured out using state
         self.line = getattr(token, 'line', '?')
         self.column = getattr(token, 'column', '?')
@@ -204,7 +208,6 @@ class UnexpectedToken(ParseError, UnexpectedInput):
         self._terminals_by_name = terminals_by_name
         self.token_history = token_history
 
-        super(UnexpectedToken, self).__init__()
 
     @property
     def accepts(self):
@@ -236,10 +239,10 @@ class VisitError(LarkError):
     """
 
     def __init__(self, rule, obj, orig_exc):
-        self.obj = obj
-        self.orig_exc = orig_exc
-
         message = 'Error trying to process rule "%s":\n\n%s' % (rule, orig_exc)
         super(VisitError, self).__init__(message)
 
+        self.obj = obj
+        self.orig_exc = orig_exc
+
 ###}

lark/lark.py

@@ -451,11 +451,11 @@ class Lark(Serialize):
             d = f
         else:
             d = pickle.load(f)
-        memo = d['memo']
+        memo_json = d['memo']
         data = d['data']
 
-        assert memo
-        memo = SerializeMemoizer.deserialize(memo, {'Rule': Rule, 'TerminalDef': TerminalDef}, {})
+        assert memo_json
+        memo = SerializeMemoizer.deserialize(memo_json, {'Rule': Rule, 'TerminalDef': TerminalDef}, {})
         options = dict(data['options'])
         if (set(kwargs) - _LOAD_ALLOWED_OPTIONS) & set(LarkOptions._defaults):
             raise ConfigurationError("Some options are not allowed when loading a Parser: {}"
@@ -512,11 +512,11 @@ class Lark(Serialize):
 
             Lark.open_from_package(__name__, "example.lark", ("grammars",), parser=...)
         """
-        package = FromPackageLoader(package, search_paths)
-        full_path, text = package(None, grammar_path)
+        package_loader = FromPackageLoader(package, search_paths)
+        full_path, text = package_loader(None, grammar_path)
         options.setdefault('source_path', full_path)
         options.setdefault('import_paths', [])
-        options['import_paths'].append(package)
+        options['import_paths'].append(package_loader)
         return cls(text, **options)
 
     def __repr__(self):

lark/parsers/lalr_parser.py

@@ -178,8 +178,8 @@ class _Parser(object):
             for token in state.lexer.lex(state):
                 state.feed_token(token)
 
-            token = Token.new_borrow_pos('$END', '', token) if token else Token('$END', '', 0, 1, 1)
-            return state.feed_token(token, True)
+            end_token = Token.new_borrow_pos('$END', '', token) if token else Token('$END', '', 0, 1, 1)
+            return state.feed_token(end_token, True)
         except UnexpectedInput as e:
             try:
                 e.interactive_parser = InteractiveParser(self, state, state.lexer)