Question

s = set([1,2,3])

I could do this:

1 in s

#=> True

I’m wondering without using loop, is there a way to do something like:

1,2 in s

#=>True

Answer 1

You can use set intersection:

>>> s = {1, 2, 3}
>>> t = {1, 2}
>>> s & t == t
True

Of course this still has a loop internally.

As spicavigo pointed out you can use issuperset, or more concisely you can use >= which is equivalent:

>>> s >= t
True

Again it still has a loop internally, but you probably can’t do it any better than that.

See the documentation for more information about set operations.

You can further improve performance if you create your set {1, 2} only once one your program starts and store it, rather than recreating it every time you make the test.