How do i prevent a user from entering an empty string?

Question

Code:
names = [ ]
num_of_invites = int(input("how many invites: " ))

while True:
for name in names:
if len(names) < num_of_invites:
per_invite = input("name of invite: ")
names.append(per_invite)
~snip~
Problem:
I have a problem when the user decides to enter a "ghost" invite(empty string), which will eventually be reflected in the names list.

Answer 1

If it is empty then ask again by a loop.
Else take a default value..

edit:
Chris
per_invite = input("name of invite:\n") or "chris"
print(per_invite)

or like

while True :
per_invite = input("name of invite:\n")
if per_invite :
break
print(per_invite)

edit:

#it just about taking the input name. you can adjust to your code without extra loop as you going it loop already..

hope it helps....

Answer 2

num = int(input() or "42")

Answer 3

Another attempt could ve using a try-block:

try:
x = int(input())
except:
x = 99

Answer 4

Why are you using `while True:` when you already know how many people are to be invited from <num_of_invites>?