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diff --git a/system/python/spyce/modules/automaton.py b/system/python/spyce/modules/automaton.py
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+++ b/system/python/spyce/modules/automaton.py
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+##################################################
+# SPYCE - Python-based HTML Scripting
+# Copyright (c) 2002 Rimon Barr.
+#
+# Refer to spyce.py
+# CVS: $Id$
+##################################################
+
+from spyceModule import spyceModule
+
+__doc__ = '''Automaton module allows Spyce users to create websites with
+state machine-based application flows. One can define an automaton
+programmatically using the start(), transition() and begin methods. The
+automaton is the executed (one step per request) using the step() method. This
+method accepts the current state, which should be managed by the user
+preferably via a session (keeping the information on the server), or possibly
+by get, post or cookie. The step() method then calls the recv() function on
+the given state, which returns an edge label. This edge points to the new
+state. The step() method then calls the send() method of the new state to
+generate the page content. The user should encode the new state in this
+content, or use on a subsequent request.'''
+
+SEND = 0
+RECV = 1
+EDGES = 2
+
+class automaton(spyceModule):
+  def start(self):
+    "Initialise an empty automaton"
+    self.clear()
+  def clear(self):
+    self._nodes = {}
+    self._edges = {}
+  # defining the automaton
+  def state(self, name, send, recv):
+    "Add a new automaton state"
+    self._nodes[name] = send, recv
+    self.transition(name, None, name)
+  def transition(self, state1, edge, state2):
+    "Add a new automaton transition"
+    if not self._nodes.has_key(state1):
+      raise 'state %s does not exist' % state1
+    if not self._nodes.has_key(state2):
+      raise 'state %s does not exist' % state2
+    self._edges[(state1, edge)] = state2
+  node=state
+  edge=transition
+  def begin(self, name):
+    if not self._nodes.has_key(name):
+      raise 'state %s does not exist' % name
+    self._begin = name
+  def define(self, sm, start):
+    self.clear()
+    for s1 in sm.keys():
+      self.node(s1, sm[s1][SEND], sm[s1][RECV])
+    for s1 in sm.keys():
+      for e in sm[s1][EDGES].keys():
+        self.edge(s1, e, sm[s1][EDGES][e])
+    self.begin(start)
+
+  # running the automaton
+  def step(self, state=None):
+    """Run the automaton one step: recv (old state), transition, 
+    send (new state)"""
+    if state==None:
+      state = self._begin
+    else:
+      try: _, recv = self._nodes[state]
+      except: raise 'invalid state: %s' % state
+      edge = recv()
+      try: state = self._edges[(state, edge)]
+      except: raise 'invalid transition: %s,%s' % (state, edge)
+    try: send, _ = self._nodes[state]
+    except: raise 'invalid state: %s' % state
+    send()
+
+
+# rimtodo: cached state-machines
+