Ruby | Integration | Edge Computing Tutorial

Introduction to Ruby

Ruby is a dynamic, open-source programming language with a focus on simplicity and productivity. It has an elegant syntax that is natural to read and easy to write. Ruby was created by Yukihiro "Matz" Matsumoto in the mid-1990s in Japan.

Installing Ruby

To install Ruby, you can use a version manager like RVM (Ruby Version Manager) or asdf. Here we will use RVM.

Open your terminal and run the following commands:

gpg --keyserver hkp://pool.sks-keyservers.net --recv-keys 409B6B1796C275462A1703113804BB82D39DC0E3
\curl -sSL https://get.rvm.io | bash -s stable --ruby

Once the installation is complete, you can verify the installation by running:

ruby -v

Basic Syntax

Let's start with the basic syntax of Ruby. Here's a simple "Hello, World!" program:

puts "Hello, World!"

Save the above code in a file named hello.rb and run it using the following command:

ruby hello.rb

The output should be:

Hello, World!

Variables and Data Types

Ruby supports various data types including integers, floats, strings, arrays, and hashes. Here's an example demonstrating the use of different data types:

# Integer
age = 25

# Float
height = 5.9

# String
name = "Alice"

# Array
fruits = ["apple", "banana", "cherry"]

# Hash
person = {name: "Alice", age: 25, height: 5.9}

puts age
puts height
puts name
puts fruits
puts person

Control Structures

Ruby supports various control structures such as if-else, loops, and case statements. Here's an example:

# if-else
age = 18
if age >= 18
  puts "You are an adult."
else
  puts "You are a minor."
end

# while loop
i = 1
while i <= 5
  puts i
  i += 1
end

# for loop
for i in 1..5
  puts i
end

# case statement
grade = "A"
case grade
when "A"
  puts "Excellent!"
when "B"
  puts "Good!"
when "C"
  puts "Fair!"
else
  puts "Poor!"
end

Methods

Methods in Ruby are a way to encapsulate reusable code. Here's how you define and call a method:

# Method definition
def greet(name)
  puts "Hello, #{name}!"
end

# Method call
greet("Alice")

Classes and Objects

Ruby is an object-oriented language. You can define classes and create objects in Ruby. Here's an example:

class Person
  def initialize(name, age)
    @name = name
    @age = age
  end

  def display_details
    puts "Name: #{@name}, Age: #{@age}"
  end
end

# Create an object
person1 = Person.new("Alice", 25)
person1.display_details

Modules

Modules in Ruby are a way to group related methods. They can be mixed into classes using the include keyword. Here's an example:

module Greet
  def say_hello
    puts "Hello!"
  end
end

class Person
  include Greet
end

person = Person.new
person.say_hello

File Handling

Ruby provides various methods to handle files. Here's how you can read from and write to a file:

# Writing to a file
File.open("example.txt", "w") do |file|
  file.puts "Hello, World!"
end

# Reading from a file
File.open("example.txt", "r") do |file|
  file.each_line do |line|
    puts line
  end
end

Exception Handling

Ruby provides a way to handle exceptions using the begin-rescue block. Here's an example:

begin
  # Code that may raise an exception
  result = 10 / 0
rescue ZeroDivisionError => e
  puts "Error: #{e.message}"
end

Conclusion

In this tutorial, we've covered the basics of Ruby, including its syntax, variables, control structures, methods, classes, modules, file handling, and exception handling. Ruby is a powerful and flexible language with a rich ecosystem. To learn more, you can explore the official Ruby documentation.

Ruby Tutorial