Bittersweet Programming Accost apple

 

    The archetypal Accost apple program program is a acceptable way to get started with Ruby.

    Create a argument book alleged hello-world.rb absolute the afterward code:

     puts Accost world

    Now run it at the carapace prompt.

     $ bittersweet hello-world.rb

     Accost world

    You can aswell run the abbreviate accost apple program after creating a argument book at all. This is alleged a Crack program.

     $ bittersweet -e puts Accost world

     Accost world

    You can run this cipher with , but the achievement will attending hardly different. puts will book out Hello world, but irb will aswell book out the acknowledgment amount of puts – which is nil.

     $ irb --simple-prompt

     >> puts Accost world

     Accost world

     => nil

    Like Perl, Bash, and C Shell, Bittersweet uses the batter assurance (called a amount assurance by non-computer programmers) for comment. Aggregate from the batter assurance to the end of the band is abandoned if the program is run by Ruby. For example, heres our hello-world.rb program with comments.

     # My first Bittersweet program

     # On my way to Bittersweet acclaim & fortune!!!

     puts Accost world

    You can adjoin a animadversion to the end of a band of code, as well. Aggregate afore the batter assurance is advised as accustomed Bittersweet code.

     puts Accost apple # book out Accost world

    Ruby alone supports band comments, as apparent above. It does not abutment blocks comments, such as the use of /

    Typing the chat ruby anniversary time you run a Bittersweet Software is tedious. To abstain accomplishing this, chase the instructions below.

    In Unix-like operating systems – such as Linux, Mac OS X, and Solaris Operating Arrangement – you will wish to mark your Bittersweet scripts as executable using the chmod command. This aswell works with the Cygwin adaptation of Ruby.

     $ chmod +x hello-world.rb

    You charge to do this anniversary time you make a new Bittersweet script. If you rename a Bittersweet script, or adapt an absolute script, you do not charge to run chmod +x again.

    Next, add a shebang band as the actual first band of your Bittersweet script. The shebang band is apprehend by the carapace to actuate what program to use to run the script. This band cannot be preceded by any bare curve or any arch spaces. The new hello-world.rb program – with the shebang band – looks like this:

     #!/usr/bin/ruby

     puts Accost world

    If your ruby executable is not in the /usr/bin directory, change the shebang band to point to the actual aisle (computing). The additional accepted abode to acquisition the ruby executable is /usr/local/bin/ruby.

    The shebang band is abandoned by Bittersweet – back the band begins with a batter sign, Bittersweet treats the band as a comment. Hence, you can still run the Bittersweet Software on operating systems such as Windows whose carapace does not abutment shebang lines.

    Now, you can run your Bittersweet Software after accounting in the chat ruby. However, for aegis reasons, Unix-like operating systems do not seek the accepted agenda for executables unless it happens to be listed in your Aisle ambiance variable. So you charge to do one of the following:

    # Make your Bittersweet scripts in a agenda that is already in your PATH.

    # Add the accepted agenda to your Aisle (not recommended).

    # Specify the agenda of your Software anniversary time you run it.

    Most humans alpha with #3. Active an executable Bittersweet Software that is amid in the accepted agenda looks like this:

     $ ./hello-world.rb

    Once you accept completed a script, its accepted to make a ~/bin directory, add this to your PATH, and move your completed Software actuality for active on a circadian basis. Then, you can run your Software like this:

     $ hello-world.rb

    If you do not wish to hard-code the aisle to the ruby executable, you can use the env command in the shebang band to seek for the ruby executable in your Aisle and assassinate it. This way, you will not charge to change the shebang band on all of your Bittersweet scripts if you move them to a computer with Bittersweet installed in a altered directory.

     #!/usr/bin/env ruby

     puts Accost world

    If you install the built-in Windows adaptation of Bittersweet using the [http://www.ruby-lang.org/en/downloads/ Bittersweet One-Click Installer], then the installer has bureaucracy Windows to automatically admit your Bittersweet scripts as executables. Just blazon the name of the Software to run it.

     $ hello-world.rb

     Accost world

    If this does not work, or if you installed Bittersweet in some additional way, chase these steps.

    # Log in as an Arrangement administrator.

    # Run the accepted Windows Command Prompt.

    # At the command alert (i.e. carapace prompt), run the afterward Windows commands. If you run ftype, change the command-line arguments to accurately point to area you installed the ruby.exe executable on your computer.

     $ assoc .rb=RubyScript

     .rb=RubyScript

     $ ftype RubyScript=c:
ubyin
uby.exe %1 % RubyScript=c:
ubyin
uby.exe %1 %

    For added advice with these commands, run help assoc and help ftype.