[PR]上記の広告は3ヶ月以上新規記事投稿のないブログに表示されています。新しい記事を書く事で広告が消えます。

#!/usr/bin/env python
# -*- coding: utf-8 -*-

class Interpreter:
	def __init__(self, context):
		self.cn = context
	def interpret(self):
		status = SIni()
		for s in self.cn:
			print "======================================="
			status.setCurrent(s)
			status = status.interpret()
		return status

class State:
	SONE=1
	STWO=2
	STHREE=3
	OWN=-1
	#status=[S1,S2,S3]
	#status={SONE:S1, STWO:S2, STHREE:S3}
	
	def __init__(self, current=None):
		if(self.__class__.__name__=="State"):
			raise Exception,"abstract class \"State\""
		self.current = current
		self.prestate = None
	
	def setCurrent(self, s):
		self.current = s
		return self

	def setPrestate(self, pre):
		self.prestate = pre
		return self
	
	def getStateCode(self):
		if(self.current == State.SONE): return State.SONE
		elif(self.current == State.STWO): return State.STWO
		elif(self.current == State.STHREE): return State.STHREE
		else:
			raise Exception, "SyntaxError"
	
	def isMatch(self):
		#s = (self.line)
		#print "isMatch(): "+str(self.__class__.OWN)
		if(self.getStateCode()==self.__class__.OWN):
			#print "T"
			return True
		#print "F"
		return False
	
	def delegate(self):
		#print "		DELEGATE *** "+StateFactory.Create(self.getStateCode(), self.current).__class__.__name__
		#cstate = self
		#return StateFactory.Create(self.getStateCode(), self.current).setPrestate(cstate).interpret()
		s = StateFactory.Create(self.getStateCode(), self.current)
		s.setPrestate(self)
		print "DELEGATE: "+s.prestate.tostring()
		return s.interpret()
		
	def interpret(self):
		if(self.isMatch()):
			# do approximate processing....
			return self
		else:
			return self.delegate()
			i
	def tolist(self):
		ret = [self]
		elm = self
		while not elm.prestate is None:
			ret.insert(0,elm.prestate)
			elm = elm.prestate
		return ret

	def __iter__(self):
		for el in self.tolist():
			yield el
	
	def tostring(self):
		return "State"+str(self.__class__.OWN)

class SIni(State):
	OWN=0
	def interpret(self):
		if(not self.isMatch()):
			return self.delegate()

class S1(State):
	OWN=1
	def interpret(self):
		if(self.isMatch()):
			print "! STATE(1) printing by "+self.__class__.__name__
			print "    > pre: "+self.prestate.__class__.__name__
			return self
		else:
			return self.delegate()
			
class S2(State):
	OWN=2
	def interpret(self):
		if(self.isMatch()):
			print "# state[2] printing by "+self.__class__.__name__
			print "    > pre: "+self.prestate.__class__.__name__
			return self
		else:
			return self.delegate()

class S3(State):
	OWN=3
	def interpret(self):
		if(self.isMatch()):
			print "% sTaTe{3} printing by "+self.__class__.__name__
			print "    > pre: "+self.prestate.__class__.__name__
			return self
		else:
			return self.delegate()
class StateFactory:
	status={State.SONE:S1, State.STWO:S2, State.STHREE:S3}
	@classmethod
	def Create(cls, scode, current):
		return StateFactory.status[scode](current)
		
def test():
	lis = [1,2,3,2,3]
	intp = Interpreter(context=lis)
	result = intp.interpret()
	
	print result.prestate
	print "\n"
	#for elm in result.tolist():
	for elm in result:
		print elm.__class__.__name__
	
	#while not result.prestate is None:
	#	print result.tostring()
	#	result = result.prestate
if __name__=="__main__":
	test()

=======================================
DELEGATE: State0
! STATE(1) printing by S1
    > pre: SIni
=======================================
DELEGATE: State1
# state[2] printing by S2
    > pre: S1
=======================================
DELEGATE: State2
% sTaTe{3} printing by S3
    > pre: S2
=======================================
DELEGATE: State3
# state[2] printing by S2
    > pre: S3
=======================================
DELEGATE: State2
% sTaTe{3} printing by S3
    > pre: S2
<__main__.S2 instance at 0x7f0a44f36b90>


SIni
S1
S2
S3
S2
S3