def getParsingTable(self):
if len(self.grammar_list) == 0:
self.showWarningMsg()
else:
grammar_list = self.grammar_list[:]
parsing_table = generate_table(grammar_list)
self.showParsingTable(parsing_table)
def getParsingTable(self):
if len(self.grammar_list) == 0:
self.showWarningMsg()
else:
grammar_list = self.grammar_list[:]
parsing_table = generate_table(grammar_list)
self.showParsingTable(parsing_table)
def parse_input(grammar_list,input_):
grammar = grammar_list[:]
#table = generate_input.get_table()
table = generate_table(grammar_list)
return_value = []
stack = ['0']
symbols = ['$']
if len(input_) == 0:
return "Empty string"
temp = []
for i in input_:
temp.append(i)
#input_ = raw_input("enter input\n")
input_ = temp
input_.append("$")
#print "-------------------------------------------------------------------------------------------------------------------------------------------"
#print "STACK".ljust(40),"SYMBOLS".ljust(40),"INPUT".ljust(50),"ACTION".ljust(40)
#print "-------------------------------------------------------------------------------------------------------------------------------------------"
try:
state = table[int(stack[len(stack)-1])][input_[0]]
while state != "":
current_line = {}
current_line["stack"] = str(stack)
current_line["symbols"] = str(symbols)
current_line["input"] = str(input_)
current_line["state"] = state
if state.startswith('s'):
#print str(stack).ljust(40),str(symbols).ljust(40),str(input_).ljust(50),state.ljust(40)
stack.append(state[1:])
symbols.append(input_.pop(0))
state = table[int(stack[len(stack)-1])][input_[0]]
elif state.startswith("r"):
#print str(stack).ljust(40),str(symbols).ljust(40),str(input_).ljust(50),state.ljust(40)
prev_state = state[:]
length = len(grammar[int(prev_state[1:])-1].split("->")[1].strip().split(" "))
check_eps = grammar[int(prev_state[1:])-1].split("->")[1].replace(" ","")
if check_eps != "e":
for i in range(length):
stack.pop()
next_state_num = table[int(stack[len(stack)-1])][grammar[int(prev_state[1:])-1].split("->")[0].strip()]
stack.append(next_state_num)
symbols = symbols[0:len(symbols)-length]
next_symbol = grammar[int(prev_state[1:])-1][0]
symbols.append(next_symbol)
state = table[int(stack[len(stack)-1])][input_[0]]
elif state.startswith("a"):
#print str(stack).ljust(40),str(symbols).ljust(40),str(input_).ljust(50),state.ljust(40)
state = table[int(stack[len(stack)-1])][input_[0]]
#print "-------------------------------------------------------------------------------------------------------------------------------------------"
#print "input accepted\n"
break
return_value.append(current_line)
else:
current_line = {}
#print str(stack).ljust(40),str(symbols).ljust(40),str(input_).ljust(50),state.ljust(40)
current_line["stack"] = str(stack)
current_line["symbols"] = str(symbols)
current_line["input"] = str(input_)
current_line["state"] = "reject"
#print "-------------------------------------------------------------------------------------------------------------------------------------------"
#print "input rejected\n"
return_value.append(current_line)
except KeyError:
#print "invalid symbol found in the input\nterminating the program..."
return "Invalid symbol found"
return return_value