From e4d3e74f6ae4431b43fd338b48b2389bd185ff35 Mon Sep 17 00:00:00 2001
From: Erez Shinan <erezshin+git@gmail.com>
Date: Mon, 20 Feb 2017 00:36:59 +0200
Subject: [PATCH] Finished refactoring

---
 lark/lexer.py               |  9 +++++++--
 lark/parser_frontends.py    | 17 ++++++-----------
 lark/parsers/lalr_parser.py | 16 +++++++++-------
 3 files changed, 22 insertions(+), 20 deletions(-)

diff --git a/lark/lexer.py b/lark/lexer.py
index 301d555..db5dde7 100644
--- a/lark/lexer.py
+++ b/lark/lexer.py
@@ -197,14 +197,19 @@ class ContextualLexer:
 
         self.root_lexer = Lexer(tokens, ignore=ignore)
 
-    def lex(self, stream, parser):
+        self.set_parser_state(None) # Needs to be set on the outside
+
+    def set_parser_state(self, state):
+        self.parser_state = state
+
+    def lex(self, stream):
         lex_pos = 0
         line = 1
         col_start_pos = 0
         newline_types = list(self.root_lexer.newline_types)
         ignore_types = list(self.root_lexer.ignore_types)
         while True:
-            lexer = self.lexers[parser.state]
+            lexer = self.lexers[self.parser_state]
             for mre, type_from_index in lexer.mres:
                 m = mre.match(stream, lex_pos)
                 if m:
diff --git a/lark/parser_frontends.py b/lark/parser_frontends.py
index 9e5c248..1c46d35 100644
--- a/lark/parser_frontends.py
+++ b/lark/parser_frontends.py
@@ -2,7 +2,6 @@ import re
 import sre_parse
 
 from .lexer import Lexer, ContextualLexer
-from .parsers.lalr_analysis import LALR_Analyzer
 
 from .common import is_terminal, GrammarError
 from .parsers import lalr_parser, earley
@@ -22,11 +21,9 @@ class WithLexer:
 class LALR(WithLexer):
     def __init__(self, lexer_conf, parser_conf):
         WithLexer.__init__(self, lexer_conf)
-        self.parser_conf = parser_conf
 
-        analyzer = LALR_Analyzer(parser_conf.rules, parser_conf.start)
-        analyzer.compute_lookahead()
-        self.parser = lalr_parser.Parser(analyzer, parser_conf.callback)
+        self.parser_conf = parser_conf
+        self.parser = lalr_parser.Parser(parser_conf)
 
     def parse(self, text):
         tokens = list(self.lex(text))
@@ -37,21 +34,19 @@ class LALR_ContextualLexer:
         self.lexer_conf = lexer_conf
         self.parser_conf = parser_conf
 
-        self.analyzer = LALR_Analyzer(parser_conf.rules, parser_conf.start)
-        self.analyzer.compute_lookahead()
+        self.parser = lalr_parser.Parser(parser_conf)
 
-        d = {idx:t.keys() for idx, t in self.analyzer.states_idx.items()}
+        d = {idx:t.keys() for idx, t in self.parser.analysis.states_idx.items()}
         self.lexer = ContextualLexer(lexer_conf.tokens, d, ignore=lexer_conf.ignore,
                                      always_accept=lexer_conf.postlex.always_accept
                                                    if lexer_conf.postlex else ())
 
 
     def parse(self, text):
-        parser = lalr_parser.Parser(self.analyzer, self.parser_conf.callback)
-        tokens = self.lexer.lex(text, parser)
+        tokens = self.lexer.lex(text)
         if self.lexer_conf.postlex:
             tokens = self.lexer_conf.postlex.process(tokens)
-        return parser.parse(tokens, True)
+        return self.parser.parse(tokens, self.lexer.set_parser_state)
 
 
 
diff --git a/lark/parsers/lalr_parser.py b/lark/parsers/lalr_parser.py
index 3280d01..7394f91 100644
--- a/lark/parsers/lalr_parser.py
+++ b/lark/parsers/lalr_parser.py
@@ -3,13 +3,13 @@ from ..common import ParseError, UnexpectedToken
 from .lalr_analysis import LALR_Analyzer, ACTION_SHIFT
 
 class Parser(object):
-    def __init__(self, analysis, callback):
-        self.analysis = analysis
-        self.callbacks = {rule: getattr(callback, rule.alias or rule.origin, None)
-                          for rule in analysis.rules}
-        self.state = self.analysis.init_state_idx
+    def __init__(self, parser_conf):
+        self.analysis = LALR_Analyzer(parser_conf.rules, parser_conf.start)
+        self.analysis.compute_lookahead()
+        self.callbacks = {rule: getattr(parser_conf.callback, rule.alias or rule.origin, None)
+                          for rule in self.analysis.rules}
 
-    def parse(self, seq, set_state=False):
+    def parse(self, seq, set_state=None):
         i = 0
         stream = iter(seq)
         states_idx = self.analysis.states_idx
@@ -17,6 +17,8 @@ class Parser(object):
         state_stack = [self.analysis.init_state_idx]
         value_stack = []
 
+        if set_state: set_state(self.analysis.init_state_idx)
+
         def get_action(key):
             state = state_stack[-1]
             try:
@@ -54,7 +56,7 @@ class Parser(object):
                 if action == ACTION_SHIFT:
                     state_stack.append(arg)
                     value_stack.append(token)
-                    if set_state: self.state = arg
+                    if set_state: set_state(arg)
                     token = next(stream)
                     i += 1
                 else: