I have a swift array which I want to filter, here is the array
let array = [apple,workshops,shopping,sports,parties,pantry,pen] 
I want to filt
Try this. Firstly, it filters the array to remove those elements that do not contain the search string, then uses a custom sort to prefer items that start with the search string. In general, use the Cartesian approach of splitting a problem into smaller sub-problems, rather than try to solve it all in one step.
let searchString = "p"
let array = ["apple", "workshops", "shopping", "sports", "parties", "pantry", "pen", "xyzzy"]
let filteredArray = array.filter({ $0.contains(searchString) })
filteredArray // drops xyzzy
let sortedArray = filteredArray.sorted(isOrderedBefore:  {
    switch ($0.hasPrefix(searchString), $1.hasPrefix(searchString)) {
    case (true, true):
        return $0 < $1
    case (true, false):
        return true
    case (false, true):
        return false
    case (false, false):
        return $0 < $1
    }
})
sortedArray // "pantry", "parties", "pen", "apple", "shopping", "sports", "workshops"] as required