I’m learning Python, and I have a novice question about Python initialize set. Through testing, I’ve discovered that a set can be initialized like this:
my_set = {'foo', 'bar', 'baz'}
Are there any disadvantages to doing it this way compared to the standard method of:
my_set = set(['foo', 'bar', 'baz'])
Or is it just a matter of style?
As someone who has spent a lot of time debugging nested loops, I can say the Python initialize set syntax
can help simplify some of the challenges, though it has a couple of limitations:
- Before Python 2.7, the literal syntax (
my_set = {'foo', 'bar', 'baz'}
) isn’t available.
-
{}
creates an empty dictionary instead of an empty set, which might confuse new developers.
Depending on your use case, these limitations could be minor or significant, but they’re worth keeping in mind.
Building on Babita’s point, I’d recommend using the set()
constructor for compatibility and flexibility. It works with all Python versions and can also create an empty set cleanly:
my_set = set(['foo', 'bar', 'baz'])
This method eliminates the ambiguity of {}
and ensures your code works consistently across Python versions.
I completely agree with Ian and Babita, and I’d add that if you’re specifically looking to create an empty set, you should explicitly initialize it with:
my_set = set()
This is widely considered the cleanest and most readable approach, avoiding any potential mix-ups with dictionaries. The Python initialize set syntax
shines when clarity is prioritized in your code!