split int by array of ints

intsplitter.swift

struct NumberComposition {
    var value:          Int
    var numbers:        [Int]
    var composition:    [Int] {
        return generateComposition()
    }
    
    init(of value: Int, fromNumbers numbers: [Int]) {
        self.value      = value
        self.numbers    = numbers
    }
    
    private func generateComposition() -> [Int] {
        var tempValue = self.value
        var result = [Int]()
        while tempValue > 0 {
            let filteredNumbers = numbers.filter({ tempValue >= $0 })
            guard let maxValidNumber = filteredNumbers.maxElement() else {
                fatalError("Can't break down \(self.value) with \(self.numbers)")
            }
            result.append(maxValidNumber)
            tempValue -= maxValidNumber
        }
        return result
    }
}

var result = NumberComposition(of: 27, fromNumbers: [1,2,3,4,5,7,15])
result.composition