let sourceArray = [1, 5, 10, 128, 256, 1024, 2048, 4096, 8000, 8390]

let selection1 = (sourceArray as NSArray)
    .beginQuery()    // Each query should begin with this call

    .skip(2)         // Removes first two elements from result selection
                     // Temporary result: [10, 128, 256, 1024, 2048, 4096, 8000, 8390]

    .take(3)         // Removes all elements but first three from result selection
                     // Temporary result: [10, 128, 256]

    .endQuery()      // This method returns result of selection
                     // In current case, result is an array equal to [10, 128, 256]


let selection2 = (sourceArray as NSArray)
    .beginQuery()
    .skip(4)         // Temporary result: [256, 1024, 2048, 4096, 8000, 8390]
    .take(2)         // Temporary result: [256, 1024]
    .contains({
        // Checks whether at least one element is more than 300
        ($0 as! Int) > 300
    })
    .endQuery()      // Returns boolean value equal to true


/*
 * Let's assume we want to check whether
 * all elements of array are bigger than 20
 */

let selection3 = (sourceArray as NSArray)
    .beginQuery()
    .all({
        ($0 as! Int) > 20
    })
    .endQuery()    // Returns true


/*
 * Another case showing
 * how you can process data in the array.
 */

let selection4 = (sourceArray as NSArray)
    .beginQuery()
    .filter({
        // Selects all elements that are bigger than 200
        ($0 as! Int) > 200
    })
    .obtain({
        // Multiply each number in array by 2 times
        ($0 as! Int) * 2
    })
    .sort({
        // Sort in descending order
        ($0 as! Int) > ($1 as! Int)
    })
    .endQuery()    // Returns [16780, 16000, 8192, 4096, 2048, 512]


/*
 * You can also select first or last value from the array.
 */

let selection5 = (sourceArray as NSArray)
    .beginQuery()
    .first()
    .endQuery()

let selection6 = (sourceArray as NSArray)
    .beginQuery()
    .last()
    .endQuery()


/*
 * Also it's possible to cast result array to required type.
 */

let selection7 = (sourceArray as NSArray)
    .beginQuery()
    .cast(NSNumber.self)
    .endQuery()