How do I reduce multiple nested if statements in Python?

Question

I'm working with a code snippet that iterates over an object list and filters out objects to perform a specific task. The for loop consists of multiple nested if statements (and I'll probably add more in the future).

Here's my code:

for obj in objects:
  if 'x' not in obj.name:
    if 'y' not in obj.name:
      if 'z' not in obj.name:
        if obj.length > 0:
          if obj.is_directory == True:
            
            # Do Something

Is there a neat or efficient workaround for this snippet?

Please Advise

common technique is inversing the condition and using early returns/break/continue. — The Fool
– The Fool, Commented May 5, 2022 at 7:00

user2246849 · Accepted Answer · 2022-05-05 07:21:44Z

5

You can also write:

for obj in objects:
   if not any(c in obj.name for c in 'xyz') and obj.length > 0 and obj.is_directory:
      # Do something

In case x, y and z are not single characters the solution remains the same. A string in Python is a sequence of characters, so you can substitute the 'xyz' string with the sequence (list) of words. You can put any iterable in there as well.

for obj in objects:
   if not any(w in obj.name for w in [word1, word2, word3]) and obj.length > 0 and obj.is_directory:
      # Do something

edited May 5, 2022 at 7:21

answered May 5, 2022 at 6:56

user2246849

4,4371 gold badge15 silver badges17 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

The Singularity Over a year ago

The x, y, z in my actual case are words like word1, word_2, _word3 how do I use that in your answer?

user2246849 Over a year ago

@Luke I edited my answer with a short explanation.

Emi OB · Accepted Answer · 2022-05-05 06:54:11Z

2

You can put them all into one if statement with and between each condition:

for obj in objects:
    if ('x' no in obj.name) and ('y' not in obj.name) and ('z' not in obj.name)
    and (obj.length > 0) and (obj.is_directory):
        #Do Something

Note that it is not necessary to check if obj.is_directory == True, and it will evaluate to true itself if it is true.

answered May 5, 2022 at 6:54

Emi OB

3,3953 gold badges20 silver badges40 bronze badges

Collectives™ on Stack Overflow

How do I reduce multiple nested if statements in Python?

2 Answers 2

2 Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

2 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related