.. Prerequisites
.. -------------

.. None

.. Author : Primal Pappachan
   Internal Reviewer : Kiran Isukapatla
   Date: May 10 , 2012
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Script
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.. L1

{{{ Show the first slide containing title, name of the production team along with the logo of MHRD}}}

i.. R1

Hello friends and welcome to the tutorial on 'Version Control with Hg'

.. L2

{{{Show the slide containing the objectives}}}

.. R2

At the end of this tutorial you will be able to

1. Understand what is Version Control.

#. Identify the need for using Version Control.

#. Install Mercurial.

.. L3

{{{Show the slide 'what is version control'}}}


.. R3

First, let's understand what 'Version Control' is. 'Version control' is a way to track files over time and share them. This allows access to earlier versions of a file(s) if and when required. It therefore enables us to make changes to the content of a file, view it's change log and collaborate on a single piece of work with a team of people.
 

.. L4

{{{Show the slide 'Home-brewed'}}}

.. R4

Let's look at an example of home-brewed Version Control system.

Version control is a way of backing up files, before making changes. Most people would have cooked up their own version control system, without realizing, there were tools built by others, that performs the task in a more organized and systematic way.  

.. L5

{{{Show the slide 'Problems'}}}

.. R5

Let's look at the various problems associated with this set-up.

1. Name and changes made are not related or linked.

#. Can’t track sequence of changes made to a file.

#. Does not scale.


.. L6

{{{Show the slide 'The need for Version Control'}}}

.. R6

Now, let's move to identifying the needs for a 'Version Control System'.

We have seen that one of the main motivations to use a Version Control system is the ability to go back to a working version of a file, when something goes wrong. Below are a few more advantages of using an automated version control system.

1. By tracking the history of a project, any person may see the evolution of a project.

#. Allows for effective collaboration on a project, as everything is shared.

#. Helps to identify which additions have broken down a project and thus aids in efficient tracking down of the bugs.

#. It is good for a one man show as it is for a big group of people working on a project.


.. L7

{{{Show the slide 'How does it work? - Analogy}}}

.. R7

It is, in some ways, similar to playing a video game. We generally play games in stages. While playing, we save the game at some instances as per our choice. We continue playing, but we could, if necessary, choose to go back to one of the saved states and start over. In this manner, we could change the state of the game.

.. L8

{{{Show the slide 'Mercurial or hg'}}}

.. R8

mercurial or hg is:

1. Easy to learn and use
    
#. Lightweight

#. Scales excellently

#. Written in Python

Some of the Version Control tools available and used widely are:

cvs, svn, git and so on.

Each of these tools have their own merits and demerits. In this tutorial we shall learn how to use mercurial or hg.

.. L9

{{{Show the slide 'Installation'}}}

.. R9

Let's now get into Installation

sudo apt-get install mercurial

$hg

and 'hg version' which gives the version number.

$hg version


.. L10

{{{Show the 'summary' slide'}}}

.. R10

This brings us to the end of the tutorial. In this tutorial, we have
learnt:

1. What is Version Control.

#. Identify the need for using Version Control

#. Install Mercurial.

.. L11

{{{Show self assessment questions slide}}}

.. R11

Here are some self assessment questions for you to solve

1. Is Mercurial a Centralized VCS or Distributed
VCS? Justify your reasoning.

#. How can you verify whether Mercurial has been
installed properly?

#. What is the command for accessing built-in help
system of Mercurial?

.. L12

{{{Show the solutions slide to self assessment questions }}}

.. R12

And the answers,

1. Mercurial is a Distributed Version Control system.

#. hg version

#. hg help command


.. L13

{{{Show the thank you slide}}}

.. R13

Hope you have enjoyed this tutorial and found it useful.
Thank you