Ring/Lessons/Demo Programs

Demo Programs In this chapter we will see simple demo programs Language Shell Main Menu Language Shell We can create simple interactive programming environment using the next program while true see nl + "code:> " give cCode try eval(cCode) catch see cCatchError done end Output: code:> see "hello world" hello world code:> for x = 1 to 10 see x + nl next 1 2 3 4 5 6 7 8 9 10 code:> func test see "Hello from test" + nl code:> test() Hello from test code:> bye Main Menu Example: # Demo Program while true see " Main Menu =========== [1] Say Hello [2] Sum two numbers [3] Stars [4] Fact [5] Exit " give nMenu see nl # we can use Switch-ON-Other-OFF instead of IF-BUT-ELSE-OK if nMenu = 1 sayhello() but nMenu = 2 Sum() but nMenu = 3 Stars() but nMenu = 4 see "Enter Number : " give x see "Output : " Try see Fact(number(x)) Catch see "Error in parameters!" + nl Done but nMenu = "5" return else see "bad option" + nl ok end func sayhello see "Enter your name ? " give fname see "Hello " + fname + nl func sum see "number 1 : " give num1 see "number 2 : " give num2 see "Sum : " see 0 + num1 + num2 func stars for x = 1 to 10 see space(8) for y = 1 to x see "*" next see nl next func fact x if x = 1 return 1 else return x * fact(x-1) ok func space x y = "" for t=1 to x y += " " next return y Output: Main Menu [1] Say Hello [2] Sum two numbers [3] Stars [4] Fact [5] Exit 1 Enter your name ? Mahmoud Fayed Hello Mahmoud Fayed Main Menu =========== [1] Say Hello [2] Sum two numbers [3] Stars [4] Fact [5] Exit 2 number 1 : 3 number 2 : 4 Sum : 7 Main Menu =========== [1] Say Hello [2] Sum two numbers [3] Stars [4] Fact [5] Exit 3 * ** *** **** ***** ****** ******* ******** ********* ********** Main Menu =========== [1] Say Hello [2] Sum two numbers [3] Stars [4] Fact [5] Exit 4 Enter Number : 5 Output : 120 Main Menu =========== [1] Say Hello [2] Sum two numbers [3] Stars [4] Fact [5] Exit 5 Ring programming language