Using map to switch List[Boolean] values

Map takes a function that maps from items _inside_ the list to other items inside, not a function of the whole list!

So it's just
  myList.map(b: Boolean => !b)
which doesn't really need the type annotation (there's only one thing it can be)
  myList.map(b => !b)
or if you use the underscore abbreviation for a completely unambiguous parameter,
  myList.map(!_)

--Rex

On Sat, Feb 18, 2012 at 11:46 PM, John <john.public66@gmail.com> wrote:

I'm trying to write a short function to take a List[Boolean] and
simply switch the values from true to false or vice versa.

Something like this:

 def boolNot(myList: List[Boolean]): List[Boolean] =
     myList.map ( myList: List[Boolean] => !myList)

Scala doesn't like the !myList at the end. Can anybody suggest how I
can write this to have the function simply negate each element in the
list?

Thanks.