Experimental parser: handling unique keys in merges

tools/lexer_generator/nfa_builder.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
 #       disclaimer in the documentation and/or other materials provided
@@ skipping 132 matching lines @@
     return (start, [end])
 
   def __continue(self, graph):
     (start, ends) = self.__process(graph[1])
     state = self.__peek_state()
     if not state['start_node']:
       state['start_node'] = self.__new_state()
     self.__patch_ends(ends, state['start_node'])
     return (start, [])
 
-  def __catch_all(self, graph):
-    return self.__key_state(TransitionKey.unique('catch_all'))
+  def __unique_key(self, graph):
+    return self.__key_state(TransitionKey.unique(graph[1]))
 
   def __join(self, graph):
     (graph, name, subgraph) = graph[1:]
     subgraphs = self.__peek_state()['subgraphs']
     if not name in subgraphs:
       subgraphs[name] = self.__nfa(subgraph)
     (subgraph_start, subgraph_end, nodes_in_subgraph) = subgraphs[name]
     (start, ends) = self.__process(graph)
     self.__patch_ends(ends, subgraph_start)
     if subgraph_end:
@@ skipping 139 matching lines @@
 
   @staticmethod
   def add_action(graph, action):
     return ('ACTION', graph, action)
 
   @staticmethod
   def add_continue(graph):
     return ('CONTINUE', graph)
 
   @staticmethod
-  def catch_all():
-    return ('CATCH_ALL',)
+  def unique_key(name):
+    return ('UNIQUE_KEY', name)
 
   @staticmethod
   def join_subgraph(graph, name, subgraph):
     return ('JOIN', graph, name, subgraph)
 
   @staticmethod
   def or_graphs(graphs):
     return reduce(lambda acc, g: ('OR', acc, g), graphs)
 
   @staticmethod
   def cat_graphs(graphs):
     return reduce(lambda acc, g: ('CAT', acc, g), graphs)
 
   __modifer_map = {
     '+': 'ONE_OR_MORE',
     '?': 'ZERO_OR_ONE',
     '*': 'ZERO_OR_MORE',
   }
 
   @staticmethod
   def apply_modifier(modifier, graph):
     return (NfaBuilder.__modifer_map[modifier], graph)