class Parser():
def __init__(self):
self.operators = {1: BNode, 2: ImNode, 4: ONode, 5: ANode}
def process(self, str):
self.analyzer = Analyzer(str)
return self.process_sentence()
# refactoring apply
def process_sentence(self):
symbol = self.analyzer.get_next_char_to_analyse()
sentence = None
# check for a false node
if symbol.symbol_type == 9:
sentence = FalseNode()
# check fot he true node
elif symbol.symbol_type == 8:
sentence = TrueNode()
# check for an variable
elif symbol.symbol_type == 10:
sentence = IdNode(symbol.content)
# check for not term
elif symbol.symbol_type == 3:
sentence = self.process_sentence()
return NtNode(sentence)
# check for opening bracket
elif symbol.symbol_type == 6:
sentence = self.process_sentence()
# check fo closing not a bracket otherwise return exception
expected_symbol = self.analyzer.get_next_char_to_analyse()
if expected_symbol.symbol_type != 7:
raise Exception("Unexpected Symbol type")
else:
raise Exception("Unexpected Node")
self.analyzer.populate_marked_index()
symbol = self.analyzer.get_next_char_to_analyse()
# check for the next symbol to be an operator to concatenate
if symbol.symbol_type in {1, 2, 4, 5}:
sentence2 = self.process_sentence()
node = self.operators[symbol.symbol_type]
return node(sentence, sentence2)
else:
self.analyzer.change_to_mark()
return sentence
