def Factor(level):
if tokenNow.tokenType == TokenType.PLUS or tokenNow.tokenType == TokenType.MINUS:
root = ExpNode(tokenNow)
MatchToken(tokenNow.tokenType)
son = Factor(level + 1)
root.addson(son)
return root
else:
return Component(level + 1)
def Atom(level):
#Msg(level, "Atom", 0)
if tokenNow.tokenType == TokenType.CONST_ID or tokenNow.tokenType == TokenType.T:
root = ExpNode(tokenNow)
MatchToken(tokenNow.tokenType)
#Msg(level, "Atom")
return root
elif tokenNow.tokenType == TokenType.FUNC:
root = ExpNode(tokenNow)
MatchToken(tokenNow.tokenType)
MatchToken(TokenType.L_BRACKET)
son = Expression(level + 1)
MatchToken(TokenType.R_BRACKET)
root.addson(son)
#Msg(level, "Atom")
return root
elif tokenNow.tokenType == TokenType.L_BRACKET:
MatchToken(TokenType.L_BRACKET)
root = Expression(level + 1)
MatchToken(TokenType.R_BRACKET)
#Msg(level, "Atom")
return root
else:
print("Atom Error!")
def Term(level):
left = Factor(level)
root = None
while tokenNow.tokenType == TokenType.MUL or tokenNow.tokenType == TokenType.DIV:
root = ExpNode(tokenNow)
MatchToken(tokenNow.tokenType)
right = Factor(level + 1)
root.addson(left)
root.addson(right)
left = root
return left
def Component(level):
left = Atom(level)
if tokenNow.tokenType == TokenType.POWER:
root = ExpNode(tokenNow)
MatchToken(tokenNow.tokenType)
right = Component(level + 1)
root.addson(left)
root.addson(right)
return root
else:
return left
def Expression(level):
left = Term(level + 1)
root = None
while tokenNow.tokenType == TokenType.PLUS or tokenNow.tokenType == TokenType.MINUS:
root = ExpNode(tokenNow)
MatchToken(tokenNow.tokenType)
right = Term(level + 1)
root.addson(left)
root.addson(right)
left = root
# left.dfs()
print(left.dfs())
return left