haskell - Can't compile because of types when using nub, map and take -


I have found this simple task: 

  bumps :: int-> (x , Y) (), (), - (int, int)] - & gt; [(Int, int]] Bumpers' bookmark listoffpp = dot (perms listOfPossiblePoints))   
 (Cartesian Points)  
 I need all permutations And only a few (bmcount) points will be required before.  
 I get the following error:  
  Actual type `[a0] 'can not match the expected type (expected type): [a0] - & gt; ; (Int, Int) Actual type: [a0] - & gt; [A0] In the first argument of `map 'in the return type of call to' le ', i.e.` `(leanazabomb le)' ​​'   
 
 
 If you remove the type signature and ask the GHCI for the type, your problem will be clear:  
  & gt; : Tea Bompless Bompless :: Eq A = & gt; Int - & gt; [A] - & gt; [[A]]   
 That is, wants to return a list of  bomb blast  lists, while you want to return it to a plain list.  
  NB  You did not tell us what the definition is, you must change either the type signature or the definition of the function.  using  perms , so I have assumed one obvious.

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