How to return TRUE/FALSE if a value does not exist in a list ??

Yes,the formula is in calculated value field, and it gives nothing (just blank) its should give true/false as the function return true/false value.

if the user email exist in the list and position field empty it returns True, and false if position field is not empty.

i need to return False if the user does not exit in the list !! any idea ?? looks like lookup is not the right function that we need in this case !!

thank you Tomasz for your help

Yes, lookup returns blank if the position is empty.

lookup("Managers", "email", Current User (Email), "Position") 

if the email does not exit in the list (my case), i cannot return True/False using

isNullOrEmpty(lookup("Managers", "email", Current User (Email), "Position"))   

if the email  exit  in the list, i can return True(when position is empty), false if position is not empty

isNullOrEmpty(lookup("Managers", "email", Current User (Email), "Position"))   

thank you

Thanks for your kind words. Good luck in Nintexing

Regards,

Tomasz