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message <<-INTRO
irb isn't a good tool for writing long programs.  Code is entered one line at a
time. You can't save your work, and you can't share it when you're done.

Instead, we write code in a file and run it from the command line.

For writing code, we use a program called a text editor.

A text editor is a word processor that saves in plain text format.  This is
unlike Word, which saves files in a special format that only Word can read.

We may have recommended a particular text editor during the Installfest, such as
SublimeText.  You can use any editor you like so long as it saves plain text.

It'll helpful to keep your text editor running, since you'll be coming back to
it often.

goals do
  goal "Use a text editor."
  goal "Write and save a Ruby program into a file"
  goal "Start and connect to the RailsBridge virtual machine"
  goal "Run Ruby code saved in a file"

step do
  message "Start your text editor."
  message "In your text editor, create a new file called **my_program.rb**"
  type_in_file "my_program.rb", <<-CONTENTS
# This is a comment line.
# Comment lines start with a pound sign, and the computer ignores them.
# Since the computer ignores them you can use them for notes to yourself.
puts 'This code is in a file!'
some_variable = 19
puts "I stored a variable with the value #\{some_variable\}!"

step do
  message <<-INFO
Save the file.

Save the file in `railsbridge` in your desktop - the folder shared with your
virtual machine. Any files your put there show up in `/vagrant` on the VM, and
vice versa, like Dropbox or Google Drive.

Did you notice we added  `.rb` at the end of the name? It's standard practice to
name Ruby files this way, to help people and tools recognize the file contains
Ruby code.

When you saved the file, your text editor may have added colors to the code.  It
recognizes the file contains Ruby, and will mark up different kinds of words
with different colors. This is called "syntax highlighting", which makes it
easier to read code.

step do
  message "Let's look at the file."
  message "Open your <a href='/ruby/command_line'>terminal</a>, and connect to the
    <a href='/ruby/using_virtual_machines'>VM</a>"
  console "ls"
  result  "my_program.rb"
  console "more my_program.rb"
  result <<-CONTENTS
puts 'This code is in a file!'
some_variable = 19
puts "I stored a variable with the value #\{some_variable\}!"
  message "**my_program.rb** was saved in plain text - you see exactlty what you
    typed.  If this were a Word document, you would see a screenful of weird
    characters and formatting, and you would get errors when you ran it."

step do
  message "Now run the code.  Stay in /vagrant on the Virtual Machine."
  console "ruby my_program.rb"
  result <<-CONTENTS
This code is in a file!
I stored a variable with the value 19!
  message "If you didn't see this message, troubleshoot with a TA. We will do
    this for the rest of the tutorial, so it's important to ensure everything

explanation do
  message "Congratulations!  You've run your first Ruby program!"
  message "Ruby programs are written in files and run from the command line. As
    your program becomes larger and larger, it may span many files!"

next_step "summary:_tools"