Somewhat cleaner version of https://gist.github.com/ColinEberhardt/b4bf4e4566ffa88afcda

Pipe Forward example

// make strings appendable
extension String {
    func append (other: String) -> String {
        return self + " " + other
    }
}

// Chainable with append method. Note that strings aren't mutated
"Hi,"
    .append("how")
    .append("are")
    .append("you?")


// Function to append b to a
func appendString (a: String, b: String) -> String {
    return a.append(b)
}

// weird
appendString("Hi,", appendString("how", appendString("are", "you?")))

// slightly less weird
appendString(appendString(appendString("Hi,", "how"), "are"), "you?")


// Curried function. Note that the arguments are swapped compared to the uncurried version
func append (appendige: String)(_ receiver: String) -> String {
    return receiver.append(appendige)
}

// Even worse than before
append("Hi,")(append("how")(append("are")("you?")))

// pipe forward as backwards function application:
// value |> function is equivalent to function(value)
// works with *any* types
infix operator |> { associativity left }
func |> <T, R> (value: T, transform: T -> R) -> R {
    return transform(value)
}

// This is nice, we can even |> println at the end to print the result
"Hi,"
    |> append("how")
    |> append("are")
    |> append("you?")
    |> println