Experimental parser: cleanup logging

tools/lexer_generator/dfa_optimizer.py

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+import logging
 from transition_key import TransitionKey
 from automaton import Term, Action, Automaton
 from dfa import Dfa
 
 # --- Optimization: Replacing tokens with gotos ---
 #
 # This optimization reduces the code size for grammars which have constructs
 # similar to keywords and identifiers. Consider the following grammar:
 #
 # "baz" <|token(BAZ)|>
@@ skipping 94 matching lines @@
 #  \--[A-Z]---> [s3]
 #
 # We can add a goto from s1 to s2 (after checking for "a"), because the
 # transitions match: with [b-z], both states transition to s2, and with [A-Z],
 # both states transition to s3. Note that [a-z] is a superkey of [b-z], and the
 # transition from s2 is defined for the superkey, but that is ok.
 
 class DfaOptimizer(object):
 
   @staticmethod
-  def optimize(dfa, log):
-    return DfaOptimizer(dfa, log).__replace_tokens_with_gotos()
+  def optimize(dfa):
+    return DfaOptimizer(dfa).__replace_tokens_with_gotos()
 
-  def __init__(self, dfa, log):
+  def __init__(self, dfa):
     self.__dfa = dfa
-    self.__log = log
 
   @staticmethod
   def __transistions_match(encoding, incoming_key, incoming_state, state):
     keys = set(state.key_iter())
     keys.add(incoming_key)
     disjoint_keys = TransitionKey.disjoint_keys(encoding, keys)
     for key in disjoint_keys:
       if not incoming_key.is_superset_of_key(key):
         continue
       transition_state = state.transition_state_for_key(key)
@@ skipping 189 matching lines @@
           orphanable.add(name(transition_state))
           match_state = DfaOptimizer.__apply_jump(
             counters, state, new_state, target_state)
           if match_state:
             states[name(state) + '_match'] = match_state
       assert not deletions
     self.__dfa.visit_all_states(replace_state)
     start_name = name(self.__dfa.start_state())
     states = self.__remove_orphaned_states(states, orphanable, start_name)
     # dump stats
-    if self.__log:
-      print 'goto_start inserted %s' % counters['goto_start']
-      print 'store_token inserted %s' % (
-        counters['store_token'])
-      print 'store_harmony_token %s' % (
-        counters['store_harmony_token'])
-      print 'transitions removed %s' % counters['removals']
-      print 'states split %s' % counters['split_state']
+    logging.info('goto_start inserted %s' % counters['goto_start'])
+    logging.info('store_token inserted %s' % (counters['store_token']))
+    logging.info('store_harmony_token %s' % (counters['store_harmony_token']))
+    logging.info('transitions removed %s' % counters['removals'])
+    logging.info('states split %s' % counters['split_state'])
     return Dfa(self.__dfa.encoding(), start_name, states)