IMP1 Ruby Tutorial

by **IMP1** Thu Jul 15, 2010 11:56 am

First off, download the Ruby Installer. It'll allow you to try out ruby by yourself.

Ruby Tutorial III - Variables

Things to know:
The puts method prints the following object as a string. Consider it to be short for 'Put Srting'.

Imagine a world where you could store a massive object (a number or a string and others not yet discorvered) in one word. Well, it's your lucky day. 'Cos that's excatly what a variable is.

One thing to remember, and that's that a variable starts with a lower-case letter, or an underscore.

Code:: my_first_variable = "The longest string in the whole wide world ever seen by a mortal other than that one mortal that saw that one string that time... but let's not go into that now, because it's a distraction from the main point, which is that this is a long string that nobody wants to type more than once."

Now whenever we use my_first_variable, we'll actually be using that string.

Input:

Code:: name = "IMP1" puts "hi " + name + "."

Output:

Code:: "hi IMP1."

That's variables and strings, and it's pretty much the same with numbers.

Input:

Code:: variable1 = 10 variable2 = 1.5 puts variable1 * (variable2 + 1)

Output:

Code:: "25"

Variables can point to integers, floats, strings... Anything that isn't a variable. Let's see what happens if we try to point a variable to a variable.

Input:

Code:: a = 10 b = a puts a puts b puts '' a = 5 puts a puts b

Output:

Code:: "10" "10" "5" "10"

Notice how the b doesn't change. It's because when you assign it to a, it doesn't really become a, it becomes what a's pointing to.

Now, wasn't that easy? A short topic because there's so little to say about variable. They're just so darn simple.

Homework:
Practise, practise, practise.

Good Hunting.

NEXT TIME: Methods.