下面是一个简单的解析器(根据示例输入进行测试)，它引入了状态设计模式。在
在现实世界中，您可能希望使用PLY之类的东西来构建一个真正的解析器。在class SimpleParser(object):
def __init__(self):
self.mode = None
self.result = None
def parse(self, text):
self.initial_mode()
self.result = []
for word in text.split(' '):
self.mode.handle_word(word)
return self.result
def initial_mode(self):
self.mode = InitialMode(self)
def bracket_mode(self):
self.mode = BracketMode(self)
def quote_mode(self):
self.mode = QuoteMode(self)
class InitialMode(object):
def __init__(self, parser):
self.parser = parser
def handle_word(self, word):
if word.startswith('['):
self.parser.bracket_mode()
self.parser.mode.handle_word(word[1:])
elif word.startswith('"'):
self.parser.quote_mode()
self.parser.mode.handle_word(word[1:])
else:
self.parser.result.append(word)
class BlockMode(object):
end_marker = None
def __init__(self, parser):
self.parser = parser
self.result = []
def handle_word(self, word):
if word.endswith(self.end_marker):
self.result.append(word[:-1])
self.parser.result.append(' '.join(self.result))
self.parser.initial_mode()
else:
self.result.append(word)
class BracketMode(BlockMode):
end_marker = ']'
class QuoteMode(BlockMode):
end_marker = '"'