Issue With Function Continuation in Python - python-3.x

Question

I know this is probably a very simple fix, but I cannot seem to make the code work. Here is the problematic excerpt:
def main_menu():
print("Welcome! Please Choose An Option to Proceed")
print("1. New: Input Letters Into A New Excel Document")
print("2. Add: Add New Letters To An Existing Excel Document")
while True:
choice = input("Enter Option Number: ")
if choice.lower() in ['1','2']:
return choice.lower()
else:
print("Invalid Number Choice")
continue
def menu_choice(main_menu):
while True:
choice = main_menu()
if choice == "1":
newsession()
elif choice == "2":
addsession()
else:
break
def newsession():
while True:
try:
txtfilenameinput = input("1. Enter 'Txt' Input File Name: ")
inputfilename = txtfilenameinput.replace(".txt" , "")
inputfile = codecs.open(inputfilename + ".txt" , "r" , encoding = "utf-8" , errors = "ignore")
print("File Found" + "\n")
break
except FileNotFoundError:
print("File Not Found: Make Sure The File Is Spelled Correctly And That Both The Program and File Is On The Desktop Screen" + "\n")
if __name__ == '__main__':
main_menu()
closeprogram = input("Press Enter Key To Close Program")
My objective is, for example, when an input of "1" is inserted in main_menu(), the script would then start to run the newsession() function. Yet for some reason, the program does nothing but jumps to the end of the script (a "press key to close program" command) without engaging the newsession() function. This holds true for an input of "2" for the addsession() function as well. What am I doing wrong? I have tried everything but nothing allows my input choice of 1 or 2 to continue the progress in my script. Thank you for your help!

Answer 1

Try the code below. It allows to exit from the program and it returns again and again for more user input:
def main_menu():
print("Welcome! Please Choose An Option to Proceed")
print("1. New: Input Letters Into A New Excel Document")
print("2. Add: Add New Letters To An Existing Excel Document")
print(" QUIT with 'q'")
while True:
choice = input("Enter Option Number: ")
if choice.lower() in ['1','2','q']:
return choice.lower()
else:
print("Invalid Number Choice")
continue
def menu_choice(main_menu):
while True:
choice = main_menu()
if choice == "1":
newsession()
elif choice == "2":
addsession()
else:
break
The problem with your code was that you were "trapped" in a while True: loop with no escape. So after ONE single user choice newsession() or addsession() were started again and again with no further progress in the script and no way to change anything about it except to kill the program. Remember: each while True loop should have at least one line containing brake or return, else it is a never ending story ...
The problem with not reaching the newsession() is HERE:
if __name__ == '__main__':
main_menu()
where it should be:
if __name__ == '__main__':
menu_choice()