Experimental parser: Abstact state matching

tools/lexer_generator/dfa_optimizer.py

 # Copyright 2013 the V8 project authors. All rights reserved.
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 #       notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 #       copyright notice, this list of conditions and the following
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@@ skipping 231 matching lines @@
     # map the old state to the new state, with fewer transitions and
     # goto actions
     def replace_state(state, acc):
       new_state = {
         'transitions' : {},
         'terminal' : state in self.__dfa.terminal_set(),
         'action' : state.action(),
       }
       states[name(state)] = new_state
       state_replacements = replacements[state] if state in replacements else {}
-      for transition_key, transition_state in state.transitions().items():
+      for (transition_key, transition_state) in state.key_state_iter():
         if not transition_key in state_replacements:
           new_state['transitions'][transition_key] = name(transition_state)
           continue
         replacement = state_replacements[transition_key]
         del state_replacements[transition_key]
         # just drop the transition
         if replacement == None:
           counters['removals'] += 1
           continue
         assert replacement == transition_state
@@ skipping 28 matching lines @@
         counters['store_harmony_token_and_goto'])
       print 'transitions removed %s' % counters['removals']
       print 'do_stored_token actions added %s' % len(store_states)
     self.__dfa = Dfa(self.__dfa.encoding(), start_name, states)
 
   @staticmethod
   def optimize(dfa, log):
     optimizer = DfaOptimizer(dfa, log)
     optimizer.replace_tokens_with_gotos()
     return optimizer.__dfa