Array extensions and helpers

Array

internal extension Array {
    internal func get(index: Int) -> Element? {
        return index >= 0 && index < self.count ? self[index] : nil
    }
    
    internal func at(indexes: [Int]) -> [Element] {
        var result: [Element] = []
        for index in indexes {
            result.append(self[index])
        }
        return result
    }
    
    internal func at(indexes: Int...) -> [Element] {
        return self.at(indexes)
    }
    
    internal func every(test: (Element) -> Bool) -> Bool {
        for element in self {
            if test(element) == false {
                return false
            }
        }
        
        return true
    }

    internal func find(test: (Element) -> Bool) -> Element? {
        for element in self {
            if test(element) {
                return element
            }
        }
        
        return nil
    }
    
    internal func findIndex(test: (Element) -> Bool) -> Int? {
        for (index, element) in enumerate(self) {
            if test(element) {
                return index
            }
        }
        
        return nil
    }
    
    internal func findLastIndex(test: (Element) -> Bool) -> Int? {
        let count = self.count
        for (index, _) in enumerate(self) {
            let reverseIndex = count - (index + 1)
            let element : T = self[reverseIndex]
            if test(element) {
                return reverseIndex
            }
        }
        
        return nil
    }
}

public func compact<T>(array: [T?]) -> [T] {
    return array.filter{$0 != nil}.map{$0!}
}

public func compact<T>(array: T?...) -> [T] {
    return compact(array)
}