def update_state(self, symstring):
statesymbol = Symbol.getERE(symstring)
if statesymbol not in self.fsm.contents[self.currstate]:
self.violated = True
else:
self.currstate = self.fsm.contents[self.currstate][statesymbol]
self.set_state_string()
def makeERE(erlist, symbols):
if type(erlist) is list:
negflag = False
orflag = False
catflag = False
andflag = False
#need some initial ERE to make sure this works correctly
currentERE = Empty()
for ind, obj in enumerate(erlist):
if obj == "*":
if ind == 0:
raise SyntaxError("Kleene closure must be after stuff")
currentERE = Kleene.getERE(currentERE)
elif obj == "~":
negflag = True
continue
elif obj == "|":
orflag = True
continue
elif obj == "+":
catflag = True
continue
elif obj == "&":
andflag = True
continue
else:
if ind == 0 | negflag:
currentERE = EREMachine.makeERE(obj, symbols)
elif orflag:
currentERE = Or.getERE(
[currentERE,
EREMachine.makeERE(obj, symbols)])
orflag = False
elif catflag:
currentERE = Concat.getERE(
currentERE, EREMachine.makeERE(obj, symbols))
catflag = False
elif andflag:
currentERE = Negation.getERE(
Concat.getERE(
Negation.getERE(currentERE),
Negation.getERE(
EREMachine.makeERE(obj, symbols))))
andflag = False
else:
currentERE = Concat.getERE(
currentERE, EREMachine.makeERE(obj, symbols))
if negflag:
currentERE = Negation.getERE(currentERE)
negflag = False
return currentERE
else:
if erlist == 'empty':
return Empty.getERE()
elif erlist == 'epsilon':
return Epsilon.getERE()
elif erlist in symbols:
return Symbol.getERE(erlist)
elif not erlist:
return
else:
raise ValueError(
'Either you have used a symbol not tied to event, or epsilon/empty is misspelled'
)
