def parse(self):
# Use one-token lookahead to determine whether it's <int>, <id>, or (<exp>)
tokNo = t.tokenizer.get_token()
if tokNo == t.Tokens.NUMBER.value:
self.__int = Int.Int()
self.__int.parse()
self.__alternative = 1
elif tokNo == t.Tokens.IDENTIFIER.value:
self.__id = Id.Id()
self.__id.parse()
self.__alternative = 2
elif tokNo == t.Tokens.OPEN_PAREN.value:
t.tokenizer.skip_token() # Consume open paren
self.__exp = Exp.Exp()
self.__exp.parse()
self.__alternative = 3
tokNo = t.tokenizer.get_token()
t.tokenizer.skip_token() # Consume closed parent
if tokNo != t.Tokens.CLOSED_PAREN.value:
print("If: Expected token {}, got token {}".format(
t.Tokens.CLOSED_PAREN.value, tokNo))
return -1
# print("Loop: Consumed `)` token.")
else:
print("Op: Invalid Next Token {}!".format(tokNo))
exit(-1)
return -1
# Successful error code
return 0
def parse(self):
# Id
self.__id = Id.Id()
self.__id.parse()
# `=` token
tokNo = t.tokenizer.get_token()
t.tokenizer.skip_token()
if tokNo != t.Tokens.EQUALS.value:
print("Assign: Expected token {}, got token {}".format(
t.Tokens.EQUALS.value, tokNo))
return -1
# print("Assign: Consumed `=` token.")
# Exp
self.__exp = Exp.Exp()
self.__exp.parse()
# `;` token
tokNo = t.tokenizer.get_token()
t.tokenizer.skip_token()
if tokNo != t.Tokens.SEMICOLON.value:
print("Assign: Expected token {}, got token {}".format(
t.Tokens.SEMICOLON.value, tokNo))
return -1
# print("Assign: Consumed `;` token.")
# Successful error code
return 0
def parse(self):
# Parse based on one token look ahead
x = int(self.t.peek())
if x == 31:
self.i = Int.Int(self.t)
self.i.parse()
elif x == 32:
self.case = 1
self.idName = self.t.getValue()
self.id = Id.Id(self.t)
self.id.parse()
elif x == 20:
self.case = 2
self.t.getToken()
self.e = Exp.Exp(self.t)
x = int(self.t.getToken())
if x != 21:
print "Expected end parenthesis."
exit()
else:
print "Invalid op."
exit()
def __init__(self, t):
self.e = Exp.Exp(t)
self.id = Id.Id(t)
self.t = t
def exp(x):
return Exp(float(x))
