@KevinCruijssen If what you want to do is check if the list is in the list of lists, you should have the lists reversed. It would result in [-1,-1] though and .k results in -1.
@Emigna Ah, you're right, I mixed them up.. I would still expect an output of 3 instead of -1 though.
Also, regarding the code provided by @MagicOctopusUrn above. Shouldn't €Z work exactly the same as εZ}? I know Z doesn't pop the list, but shouldn't € also just take the top of the list as mapped value like the ε..
@Adnan I think .Λ is bugged right now. It works exactly the same as Λ, even though the docs say it is saved as a string. But I can't do anything with this string. Can't replace or insert characters, nor use .B to convert it to a newline delimited string-list.