Difference between revisions of "Ruby/C2/Hello-Ruby/English-timed"
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Revision as of 16:47, 16 November 2015
| Time | Narration |
| 00:00 | Welcome to the Spoken Tutorial on Hello Ruby!. |
| 00:04 | In this tutorial, we will learn |
| 00:06 | * What is Ruby? |
| 00:08 | * Features |
| 00:09 | * RubyGems & Help on Ruby |
| 00:12 | Installation |
| 00:13 | Running Ruby code |
| 00:15 | Commenting |
| 00:16 | Difference between puts and print. |
| 00:19 | Here we are using:
|
| 00:27 | To follow this tutorial, you must be connected to internet. |
| 00:30 | You must have knowledge of using Terminal and Text editor in Linux. |
| 00:37 | Now I will explain what is Ruby. |
| 00:40 | Ruby is an object-oriented, interpreted scripting language. |
| 00:44 | It is dynamic, open source programming language. |
| 00:48 | It has an elegant syntax that is natural to read and easy to write. |
| 00:54 | Now, let us see some features of Ruby. |
| 00:57 | Ruby is highly portable. |
| 00:59 | Ruby program runs in any operating system. |
| 01:04 | Variables in Ruby have no datatype such as in Smalltalk, BASIC or Python. |
| 01:11 | It supports automatic memory management. |
| 01:14 | Ruby is free format language. |
| 01:17 | You can start writing your program from any line and column. |
| 01:21 | Ruby is used for developing Internet and Intra-net applications. |
| 01:26 | One of the most important features of Ruby is RubyGems. |
| 01:31 | RubyGems is a package manager for Ruby programming language. |
| 01:36 | It provides a standard format for distributing Ruby programs and libraries. |
| 01:42 | You can create and publish your own gems. |
| 01:46 | For more information on RubyGems, visit the following link. |
| 01:51 | To get more help on Ruby, you can visit the links shown. |
| 01:55 | You can install Ruby using the Ubuntu Software Centre. |
| 01:59 | For more information on Ubuntu Software Centre, please refer to the Ubuntu Linux Tutorials on this website. |
| 02:07 | Other methods for installing Ruby are as shown in this slide. |
| 02:12 | Ruby code can be executed in 3 ways- |
| 02:16 | * Command line |
| 02:17 | * Interactive Ruby |
| 02:19 | * As a file. |
| 02:20 | We will go through each method of execution. |
| 02:23 | First, let us see how to execute the Hello World code from command line. |
| 02:28 | Open a terminal by pressing the Ctrl, Alt and T keys simultaneously. |
| 02:33 | A terminal window appears on your screen. |
| 02:37 | Type the command: |
| 02:38 | ruby space hyphen e space within single quotes puts space then within double quotes Hello World and |
| 02:50 | press Enter. |
| 02:53 | We get the output as HelloWorld. |
| 02:56 | puts command is used to print the output on the terminal. |
| 03:00 | The hyphen 'e' flag allows only a single line of code to be executed. |
| 03:06 | Multiple hyphen 'e' flags can be used to execute multiple line commands. |
| 03:11 | Let's try this out. |
| 03:13 | Now, press the up-arrow key to get the previous command and |
| 03:18 | type: space hyphen e space within single quotes puts space 1+2 and |
| 03:30 | press Enter. |
| 03:32 | We get the output as Hello World and 3. |
| 03:36 | Let's switch back to our slide. |
| 03:38 | We will now learn about Interactive Ruby. |
| 03:42 | Interactive Ruby allows the execution of Ruby commands with immediate response. |
| 03:48 | You can run Ruby statements and examine the output and return values. |
| 03:53 | For older version of Ruby, install irb separately. |
| 03:57 | Now, let us execute our Ruby code through irb. Go to the terminal. |
| 04:03 | Type "irb" and press Enter |
| 04:06 | to launch the Interactive Ruby. |
| 04:09 | Type: puts space within double quotes Hello World and press Enter. |
| 04:19 | We get the output as Hello World. |
| 04:22 | And We get the return value as nil. |
| 04:25 | To exit from irb , type exit and press Enter. |
| 04:31 | You can also run Ruby program from a file. |
| 04:34 | You can use any text editor of your choice to write the code. |
| 04:39 | I am using gedit text editor. Let me switch to gedit text editor. |
| 04:45 | Now, type: puts space within double quotes Hello World . |
| 04:54 | Let's learn how to add multiple line or block comments. |
| 04:59 | Before the puts command, |
| 05:01 | type: equal to begin and press Enter. |
| 05:06 | equal to begin is used to start the comment. |
| 05:10 | Type the comments that you wish to add. |
| 05:13 | I will type: "My first Ruby program" |
| 05:20 | and press Enter. |
| 05:22 | Then type: "This code will print helloworld" and press Enter. |
| 05:30 | Now, type: equal to end. |
| 05:32 | equal to end is used to end the multiple line comments. |
| 05:37 | Comments are useful to understand the flow of program. |
| 05:41 | It is useful for documentation. |
| 05:45 | Now, let us save the file by clicking on the Save button. |
| 05:50 | It is a good practice to save the file frequently. |
| 05:53 | The Save As dialog-box appears on your screen. |
| 05:57 | Browse the location where you want to save the file. |
| 06:01 | On Desktop, I will create a folder named "rubyprogram". |
| 06:06 | We will save the file inside this folder. |
| 06:10 | In the Name text-box, type the name that you wish to add. |
| 06:14 | I will type "hello.rb". |
| 06:17 | dot rb extension is given to a Ruby file. |
| 06:21 | Then click on Save button to save the file. So, the file is saved now. |
| 06:28 | To execute the code, go to the terminal. |
| 06:32 | Let's clear the terminal first. |
| 06:35 | Make sure that you are in the directory where your Ruby file is present. |
| 06:39 | Remember that we are in the home directory. We need to go to the sub-directory rubyprogram. |
| 06:47 | To do so, type: cd space Desktop/rubyprogram and press Enter. |
| 07:00 | Let's execute the file. Type: ruby space hello dot rb and press Enter. |
| 07:10 | We get the output: "HelloWorld". |
| 07:13 | Now, let me demonstrate the difference between puts and print statement. |
| 07:18 | We will try this out using irb. |
| 07:22 | Before that, we need to go back to the home directory. To do so, type "cd" and press Enter. |
| 07:31 | Now, type irb and press Enter to launch the Interactive Ruby. |
| 07:39 | Type: puts space within double quotes Hello comma within double quotes World . |
| 07:50 | Here, comma is used to join the two puts commands together. |
| 07:55 | Now, press Enter. |
| 07:57 | We get the output Hello World, but on separate lines. |
| 08:03 | Now, let's try the same thing with print. |
| 08:06 | Press up-arrow key to get the previous command. |
| 08:09 | Replace puts with print and press Enter. |
| 08:14 | We get the output as Hello World but on the same line. |
| 08:19 | The keyword puts adds a newline to the end of the output. The keyword print does not. |
| 08:27 | The keyword print outputs only what we have provided. |
| 08:31 | This brings us to the end of this Spoken Tutorial. Let us switch back to our slides. |
| 08:37 | In this tutorial, we have learnt: |
| 08:39 | * About Ruby |
| 08:41 | * Installation |
| 08:42 | * Execution of Ruby code |
| 08:44 | * Adding multiple comments using =begin and =end |
| 08:50 | * Difference between puts and print. |
| 08:53 | As an assignment, |
| 08:55 | write a program to print your name and age. |
| 08:58 | We used multiple line comments in this tutorial. |
| 09:01 | Try to give single line comment. |
| 09:04 | Watch the video available at the following link. |
| 09:07 | It summarizes the Spoken Tutorial project. |
| 09:10 | If you do not have good bandwidth, you can download and watch it. |
| 09:15 | The Spoken Tutorial Project team: |
| 09:17 | * Conducts workshops using spoken tutorials. |
| 09:20 | * Gives certificates to those who pass an online test. |
| 09:24 | For more details, please write to: contact@spoken-tutorial.org |
| 09:30 | Spoken Tutorial project is a part of Talk to a Teacher project. |
| 09:34 | It is supported by the National Mission on Education through ICT, MHRD, Government of India. |
| 09:41 | More information on this mission is available at below link. |
| 09:45 | This is Afrin Pinjari from IIT Bombay, signing off. |
| 09:50 | Thank you for watching. |
Contributors and Content Editors
Devraj, PoojaMoolya, Pratik kamble, Ranjana, Sandhya.np14, Sneha
