jruby ruby

Ruby interaction with command line

Ruby have a way to execute command line program using back tick. Enclosed our statement to be executed by command line using back tick.

Lets try using back tick on irb !

we can put the output to a variable to process it like sample below.

ls is a command to list content of your file system, if you wonder …

bye and good night …

jruby ruby

Alternative Syntax of Ruby Hashes

Hashes variant 1

cars = { “car1” => “avanza”, “car2” => “innova”, “car3” => “mirage” }

Hashes variant 2

cars = {  :car1 => “avanza”,  :car2 => “innova”,  :car3 => “mirage” }

Hashes variant 3

cars = {  car1: “avanza”,  car2: “innova”,  car3: “mirage” }


These are as far as i know.

DragonflyBSD editor html css javasript jruby OpenBSD ruby

Bluefish editor for programming

If you a programmer you can use vi or vim or nano to code. Sometimes it just not enough feature or give comfort. I use an editor called bluefish. Install it from package like this :

For openbsd do pkg_add bluefish

If installing for openbsd dont forget to set your PKG_PATH env variable.

For Dragonfly BSD do pkg install bluefish

Bluefish have a good support for html tags and ruby language. See bluefish screenshot below.

Happy coding all !


jruby ruby

Ruby Unique Feature – Block

Block is an interesting ruby languange feature. Block is statements enclosed together using do end or curly braces {}. We can find block in action at code that iterating  an array variable.

Lets try block on irb (interactive ruby)  !!!

Sample above creating variable x which is an array of string. Next command iterating the array using each method and a block passed to it. The block have a parameter named n and n will contain each array element passed to it by each method. Code inside block print output to screen.

Below is an example of block using curly braces.

That is simple examples of block in ruby language. It is an unique and usefull feature.

Bye for now !

jruby ruby

Ruby Unique Feature – Open Classes

Open Classes

A class in ruby can be modified by adding method or variable at any point in the code.

Sample code as follow :

class ClassA
  def method1
   puts '1'

var1 =

class ClassA
 def method2
 puts '2'



jruby ruby

Ruby Unique Feature – Hashes


A hash is a collection of key and value pairs. Use curly braces {} to define a hash. Use brackets [] to get a value of a key from a hash.

Define a hash like below

nations = { ‘ID’ => ‘Indonesia’ , ‘MY’ => ‘Malaysia’, ‘SG’ => ‘Singapore’ }

To add a key value pair to hash

nations[‘BN’] = ‘Brunei Darussalam’

To output value of a key in hash

puts nations[‘ID’]

To output a hash entirely

puts nations

Bye for now !

jruby ruby

Testing MD5 and SHA256 hashing in ruby

Module : Digest::MD5 and Digest::SHA256

Method : hexdigest

Sample code on interactive ruby as follow

now we can hash our password to database !!!

jruby OpenBSD postgresql ruby

Ruby Sequel Web Application

Finally im able to create a simple web application using ruby with sinatra,sequel, postgres.

jruby OpenBSD

Exploring Ruby ORM : Sequel gem

For Jruby, install sequel gem as follow

jruby OpenBSD ruby

Ruby/Jruby : List installed files by a gem

To list installed files by a gem execute command :

jruby -S gem contents [gem_name]

For example to show files from jdbc-h2 gem we do as follow

try it for ruby

gem contents [gem_name]

bye for now …