Why Does `List(List('A', 'B'), List(1, 2)).Contains(List(1, 2))` return false?

List(List('A', 'B'), List(1, 2)).Contains(List(1, 2))
returns false, I would expect it to return true

How can I do a similar comparison searching for matching sublists of lists?

Hi @Connor_McCormick1!

I would expect the same…

I suspect that the comparison is made on the flattened list of values, as

ListCombine(List('A', 'B'), List(1, 2)).Contains(List(1, 2))

does work.

Is this a viable workaround for you?

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I think I responded to this a while ago but cannot find the thread.

The thing is, if you write .Contains(List(1, 2)), it unwraps the list in the brackets and tries to match whether your list of lists contains values 1 or 2 on themselves. I think the behavior is like that so that people matching on ListOfValues.Contains(Table.Column) would work as expected: unwrap the list of values from the column and try to match on items individually.

The workaround is to wrap in yet another list:

  List(1, 2),
  List(3, 4)
).Contains(List(List(1, 2)))
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Ah right! You did give me that same answer previously. Hard to remember to do that. Would be nice if there were a ContainsList formula that implicitly wrapped the sublist