Hello World for non-programmers 新手程式設計師的第一段Swift程式

Update: January 10, 2016 - Add the print commands for Swift 2 and add a link to IBM Swift Sandbox.

Hello World - The first step in learning a new programming language. It usually displays a simple string on the terminal / console.

Execute the code below in IBM Swift Sandbox with the RUN button and try to modify the constants and variables in the code.
在IBM Swift Sandbox中按RUN按鈕並嘗試改改程式中的常數及變數

//Swift 1:

//println("Hello World!")
//Swift 2:
print("Hello World!")

//Console output: Hello World!

//No ";" is required

let temperature = 20

let 我的常數 = 50

//Constant 常數

//Support Unicode 支援Unicode編碼 
//Type: Int  //Int整數型態(Integer)
//Initial value is required. 需要初始值
print(temperature)
print(我的常數)
// \n standards for a new line character(return to a new line)
// \n 表示換行字元
print("Add a new line character here.\n")

let helloStr = "Hello"
print(helloStr)

//Characters included in two quotation marks are known as a string. For example, "Yes" is a string.
//引號內所包含的字元稱為字串，例如，"Yes"是個字串

var mystr = "Hi ABC"

//Variable 變數
//Type: String //字串型態(Integer)
//Initial value is required. //需要初始值

//Swift 1:
//println("I want to say: \(mystr)")

//Swift 2:
print("I want to say: \(mystr)")
//Console output: I want to say: Hi ABC

mystr += "DE"
//mystr becomes "Hi ABCDE"
//Strings may be "added"

//Swift 1:
//println("I want to say: \(mystr)")

//Swift 2:
print("I want to say: \(mystr)")

//Comments will not be executed by the compiler.
//註解不會被編譯器執行

//單行註解

//Single-line comment 

//多行註解

/* Multiple-line

   Comment */

/* Nested

/* Multiline */

   Comments  */

//This is different from C. 巢狀註解
//Good design for quick debugging

//Strings may be joined together with the + sign
//可用+號將字串連接起來
let word1 = "The"
let word2 = "End"
print(word1 + " " + word2)