apparentsoft

add1 xs n c
	| c < 0 = reverse $ add1 (reverse xs) n (abs c)
	| c > 0 = add1' xs n c
	| c == 0 = add1' xs n (length xs)
	where 
		add1' [] _ _ = []
		add1' xs n 0 = xs
		add1' (x:xs) n c
			| x == n = x+1:(add1' xs n (c-1))
			| otherwise = x:add1' xs n c

apparentsoft

The output for the code below is as following, on my Mac. So, the first time that I ask to read the Tags it won't return localized filename or the UTI. But it will on a next invocation of the same code. Duh!


2013-10-24 00:10:26.780 Untitled 3[39076:507] Attributes WITHOUT Tags: {
    NSURLContentAccessDateKey = "2013-10-23 12:38:49 +0000";
    NSURLContentModificationDateKey = "2013-10-23 10:33:50 +0000";
    NSURLLocalizedNameKey = Applications;
    NSURLTypeIdentifierKey = "public.folder";
}
2013-10-24 00:10:26.781 Untitled 3[39076:507] Attributes WITH Tags: {

apparentsoft

operator infix ||| {associativity left precedence 100}

func ||| <T>(lhs:T?, rhs: @auto_closure () -> T) -> T {
    if let alhs = lhs {
        return alhs
    } else {
        return rhs()
    }
}

apparentsoft

func noNils(optionals:[Any?]) -> Bool {
    for item in optionals {
        if item == nil {
            return false
        }
    }
    return true
}

func allSome<A,B>(a:A?, b:B?) -> (A,B)? {

apparentsoft

func catOptionals<T,S where S:SequenceType, S.Generator.Element == Optional<T>>(optionals: S) -> [T] {
    return reduce(optionals, []) { (acc, value: T?) -> [T] in
        switch value {
        case let .Some(v): return acc + [v]
        default: return acc
        }
    }
}