errorWrap.swift

enum TheirError: ErrorType {
	case Something
}


enum MyError: ErrorType {
	case CouldNot(TheirError)
}

func Foo() throws -> String {
	throw TheirError.Something
	//return "x"
}




// Meh
// ------------
let s: String
do {
	s = try Foo()
} catch let err as TheirError {
	throw MyError.CouldNot(err)
}



// Experiment (which I surely won't use because it's still too weird ;-)
// ------------

func errorWrap<Result, OriginalError: ErrorType, WrappingError: ErrorType>(@autoclosure closure: () throws -> Result, _ wrapError: OriginalError -> WrappingError) throws -> Result {
	do {
		return try closure()
	} catch let x as OriginalError {
		throw wrapError(x)
	}
}


let x:String = try errorWrap(Foo(), MyError.CouldNot)