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# Used by genpytokenize.py to generate the parser in pytokenize.py
from pypy.interpreter.pyparser.automata import DFA, DEFAULT
class EMPTY: pass
def newArcPair (states, transitionLabel):
s1Index = len(states)
s2Index = s1Index + 1
states.append([(transitionLabel, s2Index)])
states.append([])
return s1Index, s2Index
# ______________________________________________________________________
def chain (states, *stateIndexPairs):
if len(stateIndexPairs) > 1:
start, lastFinish = stateIndexPairs[0]
for nStart, nFinish in stateIndexPairs[1:]:
states[lastFinish].append((EMPTY, nStart))
lastFinish = nFinish
return start, nFinish
else:
return stateIndexPairs[0]
# ______________________________________________________________________
def chainStr (states, str):
return chain(states, *map(lambda x : newArcPair(states, x), str))
# ______________________________________________________________________
def notChainStr (states, str):
"""XXX I'm not sure this is how it should be done, but I'm going to
try it anyway. Note that for this case, I require only single character
arcs, since I would have to basically invert all accepting states and
non-accepting states of any sub-NFA's.
"""
assert len(str) > 0
arcs = map(lambda x : newArcPair(states, x), str)
finish = len(states)
states.append([])
start, lastFinish = arcs[0]
states[start].append((EMPTY, finish))
for crntStart, crntFinish in arcs[1:]:
states[lastFinish].append((EMPTY, crntStart))
states[crntStart].append((EMPTY, finish))
return start, finish
# ______________________________________________________________________
def group (states, *stateIndexPairs):
if len(stateIndexPairs) > 1:
start = len(states)
finish = start + 1
startList = []
states.append(startList)
states.append([])
for eStart, eFinish in stateIndexPairs:
startList.append((EMPTY, eStart))
states[eFinish].append((EMPTY, finish))
return start, finish
else:
return stateIndexPairs[0]
# ______________________________________________________________________
def groupStr (states, str):
return group(states, *map(lambda x : newArcPair(states, x), str))
# ______________________________________________________________________
def notGroup (states, *stateIndexPairs):
"""Like group, but will add a DEFAULT transition to a new end state,
causing anything in the group to not match by going to a dead state.
XXX I think this is right...
"""
start, dead = group(states, *stateIndexPairs)
finish = len(states)
states.append([])
states[start].append((DEFAULT, finish))
return start, finish
# ______________________________________________________________________
def notGroupStr (states, str):
return notGroup(states, *map(lambda x : newArcPair(states, x), str))
# ______________________________________________________________________
def any (states, *stateIndexPairs):
start, finish = group(states, *stateIndexPairs)
states[finish].append((EMPTY, start))
return start, start
# ______________________________________________________________________
def maybe (states, *stateIndexPairs):
start, finish = group(states, *stateIndexPairs)
states[start].append((EMPTY, finish))
return start, finish
# ______________________________________________________________________
def atleastonce (states, *stateIndexPairs):
start, finish = group(states, *stateIndexPairs)
states[finish].append((EMPTY, start))
return start, finish
# ______________________________________________________________________
def closure (states, start, result = 0L):
if None == result:
result = 0L
if 0 == (result & (1L << start)):
result |= (1L << start)
for label, arrow in states[start]:
if label == EMPTY:
result |= closure(states, arrow, result)
return result
# ______________________________________________________________________
def nfaToDfa (states, start, finish):
tempStates = []
startClosure = closure(states, start)
crntTempState = [startClosure, [], 0 != (startClosure & (1L << finish))]
tempStates.append(crntTempState)
index = 0
while index < len(tempStates):
crntTempState = tempStates[index]
crntClosure, crntArcs, crntAccept = crntTempState
for index2 in range(0, len(states)):
if 0 != (crntClosure & (1L << index2)):
for label, nfaArrow in states[index2]:
if label == EMPTY:
continue
foundTempArc = False
for tempArc in crntArcs:
if tempArc[0] == label:
foundTempArc = True
break
if not foundTempArc:
tempArc = [label, -1, 0L]
crntArcs.append(tempArc)
tempArc[2] = closure(states, nfaArrow, tempArc[2])
for arcIndex in range(0, len(crntArcs)):
label, arrow, targetStates = crntArcs[arcIndex]
targetFound = False
arrow = 0
for destTempState in tempStates:
if destTempState[0] == targetStates:
targetFound = True
break
arrow += 1
if not targetFound:
assert arrow == len(tempStates)
newState = [targetStates, [], 0 != (targetStates &
(1L << finish))]
tempStates.append(newState)
crntArcs[arcIndex][1] = arrow
index += 1
tempStates = simplifyTempDfa(tempStates)
states = finalizeTempDfa(tempStates)
return states
# ______________________________________________________________________
def sameState (s1, s2):
"""sameState(s1, s2)
Note:
state := [ nfaclosure : Long, [ arc ], accept : Boolean ]
arc := [ label, arrow : Int, nfaClosure : Long ]
"""
if (len(s1[1]) != len(s2[1])) or (s1[2] != s2[2]):
return False
for arcIndex in range(0, len(s1[1])):
arc1 = s1[1][arcIndex]
arc2 = s2[1][arcIndex]
if arc1[:-1] != arc2[:-1]:
return False
return True
# ______________________________________________________________________
def simplifyTempDfa (tempStates):
"""simplifyTempDfa (tempStates)
"""
changes = True
deletedStates = []
while changes:
changes = False
for i in range(1, len(tempStates)):
if i in deletedStates:
continue
for j in range(0, i):
if j in deletedStates:
continue
if sameState(tempStates[i], tempStates[j]):
deletedStates.append(i)
for k in range(0, len(tempStates)):
if k in deletedStates:
continue
for arc in tempStates[k][1]:
if arc[1] == i:
arc[1] = j
changes = True
break
for stateIndex in deletedStates:
tempStates[stateIndex] = None
return tempStates
# ______________________________________________________________________
def finalizeTempDfa (tempStates):
"""finalizeTempDfa (tempStates)
Input domain:
tempState := [ nfaClosure : Long, [ tempArc ], accept : Boolean ]
tempArc := [ label, arrow, nfaClosure ]
Output domain:
state := [ arcMap, accept : Boolean ]
"""
states = []
accepts = []
stateMap = {}
tempIndex = 0
for tempIndex in range(0, len(tempStates)):
tempState = tempStates[tempIndex]
if None != tempState:
stateMap[tempIndex] = len(states)
states.append({})
accepts.append(tempState[2])
for tempIndex in stateMap.keys():
stateBitset, tempArcs, accepting = tempStates[tempIndex]
newIndex = stateMap[tempIndex]
arcMap = states[newIndex]
for tempArc in tempArcs:
arcMap[tempArc[0]] = stateMap[tempArc[1]]
return states, accepts
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