HelloWorld4.swift

// Add Foundation import to be able to use NSDate class below.
import Foundation

print("Hello, world!")

// There is always one argument passed, which is the name of the program,
// that is the file name.
if CommandLine.argc < 2 {
    print("No arguments are passed.")
    let firstArgument = CommandLine.arguments[0]
    print(firstArgument)
} else {
    print("Arguments are passed.")
    let arguments = CommandLine.arguments
    for argument in arguments {
        print(argument)
    }
}

let today = NSDate()
print(today)

// Instantiate FileManager class.
let fileManager = FileManager.default
// Get home directory's URL.
let homeDirURL = fileManager.homeDirectoryForCurrentUser

do {
    // Get contents of the home directory.
    let contents = try fileManager.contentsOfDirectory(atPath: homeDirURL.path)
    // Print them out.
    for content in contents {
        print(content)
    }
} catch {
    print(error)
}