Adding cython v0.20.2 in third-party.

third_party/cython/src/Cython/Plex/Machines.py

+#=======================================================================
+#
+#   Python Lexical Analyser
+#
+#   Classes for building NFAs and DFAs
+#
+#=======================================================================
+
+import sys
+
+from Transitions import TransitionMap
+
+LOWEST_PRIORITY = -sys.maxint
+
+class Machine(object):
+  """A collection of Nodes representing an NFA or DFA."""
+  states = None         # [Node]
+  next_state_number = 1
+  initial_states = None # {(name, bol): Node}
+
+  def __init__(self):
+    self.states = []
+    self.initial_states = {}
+
+  def __del__(self):
+    #print "Destroying", self ###
+    for state in self.states:
+      state.destroy()
+
+  def new_state(self):
+    """Add a new state to the machine and return it."""
+    s = Node()
+    n = self.next_state_number
+    self.next_state_number = n + 1
+    s.number = n
+    self.states.append(s)
+    return s
+
+  def new_initial_state(self, name):
+    state = self.new_state()
+    self.make_initial_state(name, state)
+    return state
+
+  def make_initial_state(self, name, state):
+    self.initial_states[name] = state
+
+  def get_initial_state(self, name):
+    return self.initial_states[name]
+
+  def dump(self, file):
+    file.write("Plex.Machine:\n")
+    if self.initial_states is not None:
+      file.write("   Initial states:\n")
+      for (name, state) in self.initial_states.iteritems():
+        file.write("      '%s': %d\n" % (name, state.number))
+    for s in self.states:
+      s.dump(file)
+
+class Node(object):
+  """A state of an NFA or DFA."""
+  transitions = None       # TransitionMap
+  action = None            # Action
+  action_priority = None   # integer
+  number = 0               # for debug output
+  epsilon_closure = None   # used by nfa_to_dfa()
+
+  def __init__(self):
+    # Preinitialise the list of empty transitions, because
+    # the nfa-to-dfa algorithm needs it
+    #self.transitions = {'':[]}
+    self.transitions = TransitionMap()
+    self.action_priority = LOWEST_PRIORITY
+
+  def destroy(self):
+    #print "Destroying", self ###
+    self.transitions = None
+    self.action = None
+    self.epsilon_closure = None
+
+  def add_transition(self, event, new_state):
+    self.transitions.add(event, new_state)
+
+  def link_to(self, state):
+    """Add an epsilon-move from this state to another state."""
+    self.add_transition('', state)
+
+  def set_action(self, action, priority):
+    """Make this an accepting state with the given action. If
+    there is already an action, choose the action with highest
+    priority."""
+    if priority > self.action_priority:
+      self.action = action
+      self.action_priority = priority
+
+  def get_action(self):
+    return self.action
+
+  def get_action_priority(self):
+    return self.action_priority
+
+  def is_accepting(self):
+    return self.action is not None
+
+  def __str__(self):
+    return "State %d" % self.number
+
+  def dump(self, file):
+    # Header
+    file.write("   State %d:\n" % self.number)
+    # Transitions
+#        self.dump_transitions(file)
+    self.transitions.dump(file)
+    # Action
+    action = self.action
+    priority = self.action_priority
+    if action is not None:
+      file.write("      %s [priority %d]\n" % (action, priority))
+
+  def __lt__(self, other):
+    return self.number < other.number
+
+class FastMachine(object):
+  """
+  FastMachine is a deterministic machine represented in a way that
+  allows fast scanning.
+  """
+  initial_states = None # {state_name:state}
+  states = None         # [state]
+                        # where state = {event:state, 'else':state, 'action':Action}
+  next_number = 1       # for debugging
+
+  new_state_template = {
+    '':None, 'bol':None, 'eol':None, 'eof':None, 'else':None
+  }
+
+  def __init__(self, old_machine = None):
+    self.initial_states = initial_states = {}
+    self.states = []
+    if old_machine:
+      self.old_to_new = old_to_new = {}
+      for old_state in old_machine.states:
+        new_state = self.new_state()
+        old_to_new[old_state] = new_state
+      for name, old_state in old_machine.initial_states.iteritems():
+        initial_states[name] = old_to_new[old_state]
+      for old_state in old_machine.states:
+        new_state = old_to_new[old_state]
+        for event, old_state_set in old_state.transitions.iteritems():
+          if old_state_set:
+            new_state[event] = old_to_new[old_state_set.keys()[0]]
+          else:
+            new_state[event] = None
+        new_state['action'] = old_state.action
+
+  def __del__(self):
+    for state in self.states:
+      state.clear()
+
+  def new_state(self, action = None):
+    number = self.next_number
+    self.next_number = number + 1
+    result = self.new_state_template.copy()
+    result['number'] = number
+    result['action'] = action
+    self.states.append(result)
+    return result
+
+  def make_initial_state(self, name, state):
+    self.initial_states[name] = state
+
+  def add_transitions(self, state, event, new_state, maxint=sys.maxint):
+    if type(event) is tuple:
+      code0, code1 = event
+      if code0 == -maxint:
+        state['else'] = new_state
+      elif code1 != maxint:
+        while code0 < code1:
+          state[chr(code0)] = new_state
+          code0 = code0 + 1
+    else:
+      state[event] = new_state
+
+  def get_initial_state(self, name):
+    return self.initial_states[name]
+
+  def dump(self, file):
+    file.write("Plex.FastMachine:\n")
+    file.write("   Initial states:\n")
+    for name, state in self.initial_states.iteritems():
+      file.write("      %s: %s\n" % (repr(name), state['number']))
+    for state in self.states:
+      self.dump_state(state, file)
+
+  def dump_state(self, state, file):
+    # Header
+    file.write("   State %d:\n" % state['number'])
+    # Transitions
+    self.dump_transitions(state, file)
+    # Action
+    action = state['action']
+    if action is not None:
+      file.write("      %s\n" % action)
+
+  def dump_transitions(self, state, file):
+    chars_leading_to_state = {}
+    special_to_state = {}
+    for (c, s) in state.iteritems():
+      if len(c) == 1:
+        chars = chars_leading_to_state.get(id(s), None)
+        if chars is None:
+          chars = []
+          chars_leading_to_state[id(s)] = chars
+        chars.append(c)
+      elif len(c) <= 4:
+        special_to_state[c] = s
+    ranges_to_state = {}
+    for state in self.states:
+      char_list = chars_leading_to_state.get(id(state), None)
+      if char_list:
+        ranges = self.chars_to_ranges(char_list)
+        ranges_to_state[ranges] = state
+    ranges_list = ranges_to_state.keys()
+    ranges_list.sort()
+    for ranges in ranges_list:
+      key = self.ranges_to_string(ranges)
+      state = ranges_to_state[ranges]
+      file.write("      %s --> State %d\n" % (key, state['number']))
+    for key in ('bol', 'eol', 'eof', 'else'):
+      state = special_to_state.get(key, None)
+      if state:
+        file.write("      %s --> State %d\n" % (key, state['number']))
+
+  def chars_to_ranges(self, char_list):
+    char_list.sort()
+    i = 0
+    n = len(char_list)
+    result = []
+    while i < n:
+      c1 = ord(char_list[i])
+      c2 = c1
+      i = i + 1
+      while i < n and ord(char_list[i]) == c2 + 1:
+        i = i + 1
+        c2 = c2 + 1
+      result.append((chr(c1), chr(c2)))
+    return tuple(result)
+
+  def ranges_to_string(self, range_list):
+    return ','.join(map(self.range_to_string, range_list))
+
+  def range_to_string(self, range_tuple):
+    (c1, c2) = range_tuple
+    if c1 == c2:
+      return repr(c1)
+    else:
+      return "%s..%s" % (repr(c1), repr(c2))