Hello World and c9 Transition

Quick reference

• 00:04 Let's start writing Ruby code.
• 00:06 So first things first, head over to your terminal.
• 00:09 And yours will look similar.
• 00:11 It'll have a different name here flat planet is the name of my PC.
• 00:14 No, I don't think the world is flat.
• 00:15 I just find it hilarious.
• 00:16 Some people do.
• 00:17 But whatever your username is, your computer name is, that will show up there.
• 00:21 So, the first thing we need to do is create a directory to hold all the files
• 00:24 that we're going to make throughout this course.
• 00:27 So type mkdir, and we want to put it in the C drive,
• 00:32 and let's call it rubycourse.
• 00:35 You can name it anything you want, but we're doing a Ruby course here.
• 00:38 Now, mkdir command will be the same if you're on Linux or a Mac.
• 00:42 But if you're on a Mac, obviously you're not going to type in C because Mac don't
• 00:46 have C drives, they have a different file structure.
• 00:48 Just go ahead and save it anywhere you want on your computer, but
• 00:51 make note of that so you can find it later.
• 00:53 Next, head over to our Sublime Text Editor.
• 00:56 And we want to go over to project, and add folder to project.
• 01:00 And then just navigate to your C drive, and find that directory we just created.
• 01:06 So we called it rubycourse there it is, single-click it to highlight it, and
• 01:09 click Select Folder.
• 01:10 And you see boom, it pops right up.
• 01:12 Now there's nothing in this directory yet.
• 01:14 So let's go ahead and create a file and save it.
• 01:16 So we've got a file that's already been opened, it's untitled.
• 01:19 So just head over here and click File > Save As.
• 01:23 And, again, navigate to your C drive and find that directory again,
• 01:28 that rubycourse, and double-click it.
• 01:31 And now let's name this file hello.rb.
• 01:36 And remember, all Ruby files end in .rb, it stands for Ruby.
• 01:40 That's how the computer knows that your program is a Ruby program, and
• 01:44 we're good to go.
• 01:45 Let's create a first Ruby program.
• 01:47 So just come over here and type puts and
• 01:51 in quotation marks Hello world.
• 01:55 Now go ahead and save this Ctrl + S on a PC, Cmd + S on a Mac or
• 01:58 you can just come over here and click File > Save.
• 02:01 Now we need to run this.
• 02:02 So let's head back over to our terminal.
• 02:04 And if we type in pwd, you can see we're currently in c/users/flatplanet.
• 02:10 And to run this file, we can run it from anywhere, but
• 02:13 it's easiest to run it from in the directory where the file is.
• 02:16 So we need to change into the directory cd change directory.
• 02:20 And we want to change into c/rubycourse, that's the directory we created.
• 02:26 And you'll notice you can see it right here, so we're definitely in there.
• 02:29 Or you could type in pwd and you see, yep, we're still in there.
• 02:33 We could type ls to list the stuff in this directory and
• 02:36 we see there's that hello.rb file.
• 02:38 So to run this, first I'm going to clear the screen here.
• 02:41 To run all ruby programs, we just type in ruby and then the name of the file.
• 02:45 So hello.rb.
• 02:48 When we do, you see a print on the screen.
• 02:50 Hello world!
• 02:51 Very cool.
• 02:52 Congratulation, you've just created your first ruby program.
• 02:55 Very, very simple and it's really just that simple.
• 02:58 Head back over to our sublime text editor and let's play around a little bit.
• 03:01 Let's add one more line here, type in system and then clear.
• 03:07 And then go ahead and save this.
• 03:09 And what this does is that it just clears this screen.
• 03:11 So let's head back over here and
• 03:13 I'm going to hit Enter a few times to kind of clutter up our screen.
• 03:16 Now let's run that file again.
• 03:17 So to run your file you can type in ruby and then hello.rb or
• 03:21 you can just hit the Up arrow key on your keyboard.
• 03:24 Ad that will just paste in the last command so that's kind of handy.
• 03:29 So, let's go ahead and run this. And boom,
• 03:31 you see it clears the screen first and then it prints out a Hello world.
• 03:35 So, that's just kind of a nice thing to do,
• 03:37 I recommend that you have that line at the top of all your ruby code throughout this
• 03:41 course just to make it easier to run and to read stuff from the terminal.
• 03:45 So very, very cool and that's our first review program.
• 03:47 In the future, if you want to add more files to our directory here,
• 03:51 you just right-click and click New File.
• 03:53 You could see it pop ups, and then we just go to File > Save As.
• 03:56 Let's call this secondprogram.rb.
• 04:02 That pops right up, we can close these.
• 04:05 In the future if we want to open them again, we just click on them, very cool.
• 04:08 If we want to delete one, we can right click and delete and it disappears,
• 04:12 very cool.
• 04:13 So we got the tools we need to program.
• 04:16 We've already written a very simple, very basic Hello World program,
• 04:20 and we're ready to go.
• 04:21 But before we move on in the course I should mention,
• 04:23 I'm going to be using a different development environment from here on out.
• 04:26 The thing that I'm going to be using is something called Cloud Nine.
• 04:30 And you can see here it is right here.
• 04:32 And this is just a simple tool that has all of these things that we've
• 04:35 already installed on one screen.
• 04:37 So you see, here's the text editor in the middle.
• 04:40 Here's my files on the left, and here's the terminal down here.
• 04:42 This is just an easier way to teach so that I have everything on the screen.
• 04:46 You actually can't use this program yourself.
• 04:48 Amazon bought this company and recently shut it down, so
• 04:50 it's not available anymore.
• 04:52 So you'll just follow along using the tools we've already set up,
• 04:55 your Sublime Text editor, and you Git Bash terminal.
• 04:57 So you know whenever I write something here,
• 05:00 you'll just obviously write it in your Sublime Text, right here, right?
• 05:05 Same exact code the same exact everything.
• 05:08 The files over here on the left hand side,
• 05:11 it will be the same files over here on your left hand side and Sublime Text.
• 05:15 And whenever I write a command down here in the terminal,
• 05:18 you'll write the exact same command in your Git Bash terminal, so
• 05:21 should be able to follow along, no problem.
• 05:24 Like I said, I just use this so it's easier to teach and
• 05:26 have everything on one screen.
• 05:28 So that's all for this video and the next video will look at comments and errors.

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