A function to union a list of lists

Stream: Is there code for X?

[Mai]

Is there no function to union a list of lists?

[Johannes Tantow]

List.flatten

[Mai]

That would contain duplicates though

[Mai]

I guess I am just looking for a foldl List.union ∅ abbreviation

[Johannes Tantow]

You could run dedup afterwards

[Aaron Liu]

Do you have to use lists? This sounds like docs#Finset.sup which can union a finset of finsets.

[Mai]

I guess I could

[Mai]

It's unfortunate you can't use a Finset in mutually recursive types