Python - Test if a list is completely True

Sometimes, we need to check if a list is completely True, these occurrences come more often in testing purposes after the development phase. Hence, having a knowledge of all this is necessary and useful. Lets discuss certain ways in which this can be performed.

Method #1 : Naive Method
In the naive method, we just run a loop from beg to end of list and check manually for each value. This is the most basic way to perform this particular task.

# Python3 code to demonstrate  
# Pure List Test 
# using naive method 
  
# initializing list  
test_list = [True, True, True, True] 
  
# printing original list 
print ("The original list is : " + str(test_list)) 
  
flag = 0
  
# using naive method  
# Pure List Test 
for i in test_list : 
    if not i : 
        flag = 1
        break
  
# printing result 
print ("Is List completely True ? : " + str(bool(not flag))) 

Output :

The original list is : [True, True, True, True]
Is List completely True ? : True

Method #2 : Using all()
This function tests each value to be True and if yes, returns boolean True, else returns false. The list iteration is done using list comprehension.

# Python3 code to demonstrate  
# Pure List Test 
# using all() 
  
# initializing list  
test_list = [True, True, True, True] 
  
# printing original list 
print ("The original list is : " + str(test_list)) 
  
flag = 0
  
# using all() 
# Pure List Test  
res = all(i for i in test_list) 
  
# printing result 
print ("Is List completely True ? : " + str(res)) 

Output :

The original list is : [True, True, True, True]
Is List completely True ? : True

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Python – Test if a list is completely True

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