HimotokiSample.swift

struct Group: Decodable {
    let name: String
    let floor: Int
    let locationName: String
    let optional: [String]?

    // MARK: Decodable

    static func decode(e: Extractor) throws -> Group {
        return try Group(
            name: e <| "name",
            floor: e <| "floor",
            locationName: e <| [ "location", "name" ], // Parse nested objects
            optional: e <||? "optional" // Parse optional arrays of values
        )
    }
}

func testGroup() {
    var JSON: [String: AnyObject] = [ "name": "Himotoki", "floor": 12 ]

    let g = try? Group.decodeValue(JSON)
    XCTAssert(g != nil)
    XCTAssert(g?.name == "Himotoki")
    XCTAssert(g?.floor == 12)
    XCTAssert(g?.optional == nil)

    JSON["name"] = nil
    do {
        try Group.decodeValue(JSON)
    } catch let DecodeError.MissingKeyPath(keyPath) {
        XCTAssert(keyPath == "name")
    } catch {
        XCTFail()
    }
}