Experimental parser: better actions

tools/lexer_generator/automaton.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 21 matching lines @@
   pass
 
 class AutomatonState(object):
 
   def __init__(self, node_number):
     self.__node_number = node_number
 
   def node_number(self):
     return self.__node_number
 
+  def __str__(self):
+    return "%s(%d)" % (type(self), self.node_number())
+
 class Automaton(object):
 
   @staticmethod
   def visit_edges(edge, compute_next_edge, visitor, state):
     visited = set()
     while edge:
       f = lambda (next_edge, state), node: (
         next_edge | compute_next_edge(node),
         visitor(node, state))
       (next_edge, state) = reduce(f, edge, (set(), state))
       visited |= edge
       edge = next_edge - visited
     return state
 
   @staticmethod
-  def generate_dot(start_node, terminal_set, edge_iterator):
+  def generate_dot(start_node, terminal_set, edge_iterator, state_iterator):
 
     def escape(v):
       v = str(v).replace('\r', '\\\\r')
       v = str(v).replace('\t', '\\\\t')
       v = str(v).replace('\n', '\\\\n')
       v = str(v).replace('\\', '\\\\')
       v = str(v).replace('\"', '\\\"')
       return v
 
     def f(node, node_content):
       for key, values in node.transitions().items():
         if key == TransitionKey.epsilon():
           key = "ε"
-        # TODO pass this action as parameter
-        if type(values) == TupleType:
-          values = [values]
-        for (state, action) in values:
+        for state in state_iterator(values):
+          action = state.action()
           if action:
-            content = "  S_%s -> S_%s [ label = \"%s {%s} -> %s\" ];" % (
+            content = "  S_%s -> S_%s [ label = \"%s {%s}:%d\" ];" % (
                 node.node_number(),
                 state.node_number(),
                 escape(key),
                 escape(action[1]),
-                escape(action[2]))
+                action[0])
           else:
             content = "  S_%s -> S_%s [ label = \"%s\" ];" % (
                 node.node_number(), state.node_number(), escape(key))
           node_content.append(content)
       return node_content
 
     node_content = edge_iterator(f, [])
     terminals = ["S_%d;" % x.node_number() for x in terminal_set]
     start_number = start_node.node_number()
     start_shape = "circle"
     if start_node in terminal_set:
       start_shape = "doublecircle"
 
     return '''
 digraph finite_state_machine {
   rankdir=LR;
   node [shape = %s, style=filled, bgcolor=lightgrey]; S_%s
   node [shape = doublecircle, style=unfilled]; %s
   node [shape = circle];
 %s
 }
     ''' % (start_shape,
            start_number,
            " ".join(terminals),
            "\n".join(node_content))