Experimental parser: remove match actions

tools/lexer_generator/nfa.py

Index: tools/lexer_generator/nfa.py
diff --git a/tools/lexer_generator/nfa.py b/tools/lexer_generator/nfa.py
index 8aa2b69088fd8f7c2a17092a888db16359b167f8..eb711b26c6318dfd953f99a9780a610a6f4e81a2 100644
--- a/tools/lexer_generator/nfa.py
+++ b/tools/lexer_generator/nfa.py
@@ -37,61 +37,45 @@ class NfaState(AutomatonState):
     self.__epsilon_closure = None
     self.__action = Action.empty_action()
 
-  def epsilon_closure_iter(self):
-    return iter(self.__epsilon_closure)
-
-  def set_epsilon_closure(self, closure):
-    assert self.is_closed()
-    assert self.__epsilon_closure == None
-    self.__epsilon_closure = frozenset(closure)
-
   def action(self):
-    assert self.is_closed()
+    assert self.__is_closed()
     return self.__action
 
   def set_action(self, action):
-    assert not self.is_closed()
+    assert not self.__is_closed()
     assert not self.__action
     assert isinstance(action, Action)
     self.__action = action
 
-  def state_iter_for_key(self, key):
-    assert self.is_closed()
-    if not key in self.__transitions:
-      return iter([])
-    return iter(self.__transitions[key])
-
-  def swap_key(self, old_key, new_key):
-    'this is one of the few mutations allowed after closing'
-    assert self.is_closed()
-    assert not new_key == TransitionKey.epsilon(), "changes epsilon closure"
-    value = self.__transitions[old_key]
-    del self.__transitions[old_key]
-    self.__transitions[new_key] = value
-
   def __add_transition(self, key, next_state):
     assert key != None
     if next_state == None:
-      assert not self.is_closed(), "already closed"
+      assert not self.__is_closed(), "already closed"
       self.__unclosed.add(key)
       return
     if not key in self.__transitions:
       self.__transitions[key] = set()
+    else:
+      assert key == TransitionKey.epsilon()
     self.__transitions[key].add(next_state)
 
   def add_unclosed_transition(self, key):
     assert key != TransitionKey.epsilon()
     self.__add_transition(key, None)
 
-  def add_epsilon_transition(self, state):
+  def add_transition(self, key, state):
+    assert not self.__is_closed(), "already closed"
     assert state != None
-    self.__add_transition(TransitionKey.epsilon(), state)
+    self.__add_transition(key, state)
+
+  def add_epsilon_transition(self, state):
+    self.add_transition(TransitionKey.epsilon(), state)
 
-  def is_closed(self):
+  def __is_closed(self):
     return self.__unclosed == None
 
   def close(self, end):
-    assert not self.is_closed()
+    assert not self.__is_closed()
     unclosed, self.__unclosed = self.__unclosed, None
     if end == None:
       assert not unclosed
@@ -101,19 +85,46 @@ class NfaState(AutomatonState):
     if not unclosed:
       self.__add_transition(TransitionKey.epsilon(), end)
 
+  def post_creation_verify(self):
+    assert self.__is_closed()
+    assert self.__epsilon_closure != None
+
+  def state_iter_for_key(self, key):
+    assert self.__is_closed()
+    if not key in self.__transitions:
+      return iter([])
+    return iter(self.__transitions[key])
+
   def key_state_iter(
     self,
     key_filter = lambda x: True,
     state_filter = lambda x: True,
     match_func = lambda x, y: True,
     yield_func = lambda x, y: (x, y)):
-    assert self.is_closed()
+    assert self.__is_closed()
     for key, states in self.__transitions.items():
       if key_filter(key):
         for state in states:
           if state_filter(state) and match_func(key, state):
             yield yield_func(key, state)
 
+  def epsilon_closure_iter(self):
+    return iter(self.__epsilon_closure)
+
+  def set_epsilon_closure(self, closure):
+    assert self.__is_closed()
+    assert self.__epsilon_closure == None
+    self.__epsilon_closure = frozenset(closure)
+
+  def swap_key(self, old_key, new_key):
+    'this is one of the few mutations allowed after closing'
+    self.post_creation_verify()
+    assert not old_key == TransitionKey.epsilon(), "changes epsilon closure"
+    assert not new_key == TransitionKey.epsilon(), "changes epsilon closure"
+    value = self.__transitions[old_key]
+    del self.__transitions[old_key]
+    self.__transitions[new_key] = value
+
 class Nfa(Automaton):
 
   def __init__(self, encoding, start, end, nodes_created):
@@ -130,7 +141,7 @@ class Nfa(Automaton):
 
   def __verify(self, nodes_created):
     def f(node, count):
-      assert node.is_closed()
+      node.post_creation_verify()
       return count + 1
     count = self.visit_all_states(f, 0)
     assert count == nodes_created
@@ -151,7 +162,7 @@ class Nfa(Automaton):
     dfa_nodes[name] = {
       'transitions': {},
       'terminal': self.__end in nfa_state_set,
-      'action' : Action.dominant_action(nfa_state_set)}
+      'action' : self.dominant_action(nfa_state_set)}
     # Gather the set of transition keys for which the dfa state will have
     # transitions (the disjoint set of all the transition keys from all the
     # states combined). For example, if a state in the state set has a